1. Introduction: instructions to contributors notes from the editor
2. Lotus Activities: reports and abstracts
3. Recent Lotus Literature
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| O Genetics | O Breeding | O Taxonomy | O Physiology |
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P. R. Beuselinck, USDA-ARS
University of Missouri
207 Waters Hall
Columbia, MO 65211 USA
FAX 573-882-1467
Purpose:
The Lotus Newsletter consists of informal
communications of research information on Lotus spp. Reports
of any phase of research on Lotus breeding, genetics, taxonomy,
management, utilization or physiology are welcome. Your biographic
sketches and information about your research objectives, approaches,
and progress including titles of your publications are encouraged.
Seed requests and news items are accepted.
This is the 27th year of publication for the
Lotus Newsletter. Now is the time
to consider contributing to the 28th volume of the Lotus
Newsletter. Contributions generally are compiled without
editing.
1. Prepare your contribution using any IBM (MS-DOS) or Macintosh word processing program. Then you have two options:
a. submit the file on 3.5 " (90 mm) disk accompanied by a printed copy of the contribution. Identify which program you used. OR
b. submit the file to my e-mail address (pbeuselinck@plantsci.missouri.edu)
and send me a hardcopy by FAX to 573-882-1467, or by regular mail.
1. Single space typewritten text on white 8.5" x 11" (21.5 cm x 27.5 cm) paper. Double space between paragraphs and tables. Do not number pages.
2. Leave a minimum of 3/4" (1.9 cm) on the left and bottom of each page.
3. On the first page of each contribution, indicate state or country, title of report, and name(s) of contributor(s).
4. Send your contributions by December 31,
1996 to:
Lotus Newsletter
Dr. P. R. Beuselinck, USDA-ARS
Plant Genetics Research Unit
207 Waters Hall
University of Missouri
Columbia, MO 65211 U.S.A.
E-mail: pbeuselinck@plantsci.missouri.edu
FAX 573-882-1467
The expense of publishing the Lotus Newsletter has been partially covered by unrestricted research support. I will continue to strive for financial support of the Lotus Newsletter to provide you with an unencumbered communication resource. Please note my comments about an internet version of the Lotus Newsletter below.
Many thanks to you who respond to my requests for information about your Lotus research. Your contributions to the Lotus Newsletter help generate a better perspective of the international research and management on the many species of Lotus.
Requests for distribution the Lotus Newsletter to university or research libraries are accepted. If you have a library that needs a copy for your research group or center please notify me. Please note my comments about an internet version of the Lotus Newsletter below.
There is a limited supply of back issues available. Supplies of most volumes have been depleted, but requests will be handled on a first-come first-served basis.
This was the last issue of the Lotus Newsletter to be printed in a hardcopy form. The cost of printing and mailing has become quite expensive. You should be able to go the Lotus Newsletter homepage and print a copy for yourself or you simply access the homepage and read the volume of your choice without filling your bookshelf. My goal is to work my way back through all the volumes until they are all in electronic format.
From the homepage you should be able to access the current volume or past volumes. The current volume for the year will be a compilation of all Lotus news and articles received between January 1 through December 31.
The internet address for the Lotus Newsletter is: http://www.plantsci.missouri.edu/lnl
If you have not filled-out and sent in a questionnaire in the last two years please complete one. If you know of others interested in the Lotus Newsletter have them submit a questionnaire and they'll be added to the mailing list.
The illustration on the cover is of Lotus conjugatus L. has again been graciously provided by Ana Arambarri (Argentina) . The Lotus illustration is the 4th in a series of illustrations that started with Volume 23.
Justification
Birdsfoot trefoil (Lotus corniculatus) possesses characteristics
that should make it well suited for use in high elevation mountain
meadows. However, its potential benefits in that environment have
not been demonstrated through research. Therefore, very few producers
ever consider birdsfoot trefoil when selecting a legume for seeding.
Most producers cut their high elevation meadows (6,000 - 10,000 ft.) once for hay and then graze any regrowth off in the fall. Birdsfoot trefoil fits this production scheme because first cutting yields are high (i.e. comparable to alfalfa) and the regrowth can be safely grazed due to birdsfoot trefoil's non-bloating characteristic. Birdsfoot trefoil also maintains good forage quality over an extended period of time because of its indeterminate growth habit and better leaf retention capabilities compared to many other legumes. This trait has positive implications for producers that cannot realistically harvest all their hay at peak quality due to constraints such as time, labor, or weather.
The addition of legumes to grass dominated meadows can increase
both the quantity and quality of forage produced. Legumes such
as red clover (Trifolium pratense), alsike clover (Trifolium
hybridum), and alfalfa (Medicago sativa) have been
successfully interseeded into mountain meadows in the past. Birdsfoot
trefoil seedlings lack vigor and do not compete well with existing
vegetation which often makes establishment difficult. The objectives
of this study were to evaluate varieties of birdsfoot trefoil
potentially adapted for use in mountain meadows and to determine
the impact of different seedbed preparations on establishment
success of the varieties.
Study Area
This study was established on the Trampe Ranch approximately 6.5
miles north of Gunnison, Colorado at 7800 ft. elevation. The soil
is classified as a Fola cobbly sandy loam (loamy-skeletal, mixed
Borollic Camborthid). Species present at the site include: common
meadow foxtail (Alopecurus pratensis), timothy (Phleum
pratense), smooth brome (Bromus inermis), Kentucky
bluegrass (Poa pratensis), red clover, alsike clover, dandelion
(Taraxacum officinale), herbaceous cinquefoil (Potentilla
pulcherrima), and alfalfa. The alfalfa was from an old interseeding
and consisted of widely scattered plants. Annual precipitation
is evenly distributed and averages 10.5 inches at Gunnison. Snowfall
averages 54 inches per year. Meadows used for forage production
are flood irrigated. The average frost-free growing season is
63 days, however, freezing temperatures can occur on any day of
the year.
Methods and Materials
Birdsfoot trefoil was seeded on May 24, 1994 at the rate of 6 lbs pure live seed/ac. Varieties evaluated were: 'Carroll', 'Norcen', 'Leo', 'Tretana', and 'Empire'. An entry of 'Empire' that was coated with clay containing the appropriate Rhizobium bacteria for root nodulation and the fungicide Apron® was also evaluated and was designated as 'Empire-C'. All other varieties were inoculated just prior to seeding with standard inoculant (Nitragin Company). Plots were seeded with a John Deere Powr-till® drill (Model 1550, 8 ft.). An unseeded plot was left as a control.
The different varieties were seeded into 3 types of seedbeds. The first consisted of seeding directly into the existing vegetation with no effort to suppress competition. The existing vegetation was approximately 4-6 inches tall at the time of seeding. This treatment was considered the control. The second seedbed treatment consisted of suppressing the existing vegetation with Roundup® sprayed 2 weeks prior to seeding at the rate of 1.5 qts/ac. Although Roundup® is supposed to kill all plants that it comes in contact with, it generally only suppresses the more vigorous perennial grasses allowing the seedlings to become established. The third seedbed treatment consisted of tilling with a tractor-mounted rototiller to a depth of about 1 inch. The objective of this treatment was to eliminate or reduce shallow-rooted species such as Kentucky bluegrass and set back the deeper-rooted, desirable perennial grasses giving the seedlings time to become established.
Experimental design was a split-block with 3 replications. Plot size for each variety/seeding method combination was 10' x 24'. Each block measured 72' x 80'. The entire study area was fertilized with 80 lbs/ac of P2O5 just prior to seeding using triple superphosphate (0-45-0).
The study area was flood irrigated under the management of the
landowner. Harvest of plots was timed to coincide with the landowner's
normal haying which occurred on August 3 in 1995. Plots were harvested
with a New Holland mower/conditioner (9 ft., 3 in. header) which
left the forage in a windrow. The center 20 ft. of each windrow
was collected and weighed to estimate production. Two grab samples
were collected per plot. The first was used to determine moisture
content and overall hay quality. The second was separated into
components of alfalfa, birdsfoot trefoil, clover, forbs, and grass
to determine hay composition. Forage quality of individual components
was also analyzed. Crude protein and invitro dry matter digestibility
were analyzed as measures of forage quality. Production and quality
estimates will be gathered for at least one more year. Persistence
will be monitored over time.
Results
Interseeding birdsfoot trefoil into existing mountain meadow vegetation increased total forage yield an average of 650 lbs/ac compared to the unseeded control (Table 1). The variety 'Empire-C' that was established using coated seed was the only one that did not significantly increase total yield above the control. For some unknown reason, the seed coating inhibited establishment of this variety instead of enhancing it. The 'Empire-C' variety contributed only 4% to total production while the other varieties contributed between 15 and 22%. The relationship between the amount of birdsfoot trefoil in the hay and total yield was strong (r = 0.97). Plots seeded to the 'Norcen' variety produced the highest total yield at just over 2 tons/ac and had the highest average contribution from birdsfoot trefoil at 22%.
Averaged across varieties, birdsfoot trefoil increased crude protein content of the hay 2.3 percentage points compared to the control (Table 2). Crude protein content of the hay was lowest from plots seeded with the 'Empire-C' variety and highest from plots seeded with either the 'Leo' or 'Norcen' varieties. As with production, this trend was related to the amount of birdsfoot trefoil in the hay (r = 0.94). Digestibility of the hay was not affected by any of the birdsfoot trefoil varieties (Table 2).
Total forage yield was not affected by either the spray or tillage seedbed preparations (Table 3). Contribution of birdsfoot trefoil to total yield was 3 times higher from plots sprayed with Roundup® and about 2 times higher from tilled plots compared to the control. This result emphasizes the need to suppress the existing vegetation in some manner prior to seeding to improve establishment success of birdsfoot trefoil. However, there were some tradeoffs associated with the different suppression methods evaluated in this study. The tillage treatment increased grass composition compared to the spray and control treatments and decreased clover composition compared to the control (Table 3). The spray treatment also decreased clover composition compared to the control.
The changes in hay composition (Table 3) due to interseeding and suppression of the existing vegetation affected both crude protein content and digestibility of the hay (Table 4). An increase in grass and decrease in clover composition led to a reduction in both crude protein content and digestibility of the hay produced from the tillage plots compared to the control. Digestibility of hay from the sprayed plots was reduced about 3 percentage points compared to the control, possibly in response to reduced clover composition. Crude protein content of hay from the sprayed plots was not affected. The contribution of crude protein from birdsfoot trefoil probably offset any loss associated with decreased clover composition.
No significant differences in crude protein content or digestibility
were measured among the birdsfoot trefoil varieties (Table 5).
Crude protein content of birdsfoot trefoil averaged 17.3% which
was comparable to clover (Table 6). These 2 components were higher
in crude protein compared to alfalfa, grass, or forbs. Birdsfoot
trefoil was also the most digestible (67.2%) compared to the other
hay components (Table 6). Crude protein content and digestibility
of alfalfa were lower than expected because of the large, robust
growth form of the plants that were present. As density of alfalfa
declines over time, the remaining plants compensate by producing
stemmier growth that is generally higher in fiber (i.e. less digestible)
and lower in crude protein.
Summary
Birdsfoot trefoil that was interseeded into a mountain meadow
increased both the quantity and quality of forage produced in
the first production year. Differences among the varieties tested
were generally small. Suppression of the existing vegetation improved
establishment success. Plots sprayed with Roundup®
prior to seeding had the highest contribution of birdsfoot trefoil
to total production. Although these results from the first production
year appear promising, persistence of the different varieties
needs to be documented before birdsfoot trefoil can be commonly
recommended for seeding in mountain meadows.
Table 1. Effect of interseeding various varieties of birdsfoot trefoil on production and composition of mountain meadow hay. Samples were taken August 3, 1995. | ||||||
|
1Variety means were averaged across seeding methods. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||||||
Table 2. Effect of interseeding various varieties of birdsfoot trefoil on crude protein concentration and invitro dry matter digestibility of mountain meadow hay. Samples were taken August 3, 1995. | ||
|
1Variety means were averaged across seeding methods. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||
| Table 3. Effect of method of seeding (i.e. vegetation suppression method) birdsfoot trefoil on production and composition of mountain meadow hay. Samples were taken August 3, 1995. | ||||||
| -----------------------------------%---------------------------------- | ||||||
|
1Seeding method means were averaged across birdsfoot trefoil varieties. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||||||
Table 4. Effect of method of seeding (i.e. vegetation suppression method) birdsfoot trefoil on crude protein concentration and invitro dry matter digestibility of mountain meadow hay. Samples were taken August 3, 1995. | ||
|
1Seeding method means were averaged across birdsfoot trefoil varieties. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||
Table 5. Crude protein concentration and invitro dry matter digestibility of various birdsfoot trefoil varieties that were interseeded into a mountain meadow. Samples were taken August 3, 1995. | ||
|
1Varieties were composited across seeding methods. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||
Table 6. Crude protein concentration and invitro dry matter digestibility of various components of mountain meadow hay following interseeding of birdsfoot trefoil. Samples were taken August 3, 1995. | ||
|
1Varieties were composited or averaged across seeding methods. 2Means within columns followed by the same letter are not significantly different (P>0.05). | ||
ABSTRACT
Seed development and maturation at different stages of pod development
were studied Lotus corniculatus. Pods were classified into
4 different stages of development using morphological characters
such as colour and size. The effect on seed quality of three different
harvesting procedures at each stage of development was studied.
The number of normal seedlings and hard seed increased with stage
of development. Direct combining resulted in the lowest germination
potential whilst highest germination potential was obtained after
threshing seed from dried plants. Collecting pods and drying them
artificially showed post harvest maturation mainly by means of
hardseedness.
INTRODUCTION
The genus Lotus belongs to the subfamily Papilionatae (Wheeler
and Hill, 1957). It consists of a diverse group of annual and
perennial species widely distributed throughout the world (Callen,
1959).Lotus corniculatus, a perennial forage legume is
utilised in several countries in different parts of the world
(Seaney and Henson, 1970: Robinson, 1934: Orsi, 1953: Panikar,
1949: Gardner and Elliot (1945). This species has advantages due
to its forage quality and ability to tolerate low phosphorous
levels in soil and drought (Formoso, 1983). However lack of sufficient
seed yield has prevented its spread (Anderson, 1955: McGraw and
Beuselinck, 1983: Buckovic, 1952: Metcalfe et al, 1957). The gap
between the theoretical and actual seed yield is enormous (Seaney
and Henson, 1970). Lack of proper guides to determine the best
moment for harvesting have been mentioned by Pieroni (1992) and
this situation may lead to loss of seeds because of dehiscence
of pods or because of damage to seed if harvest is too early.
Several authors have studied the development of seeds of forage
legume from defined points early in the process of maturation
(Pieroni, 1992: Anderson, 1955: Hare and Lucas, 1984 ). The variability
of environment in different parts of the world, seasonal variation
in weather conditions and differences in populations mean that
it is difficult to make generalisations and practical recommendations
for crop management from these studies as the timing of maturation
may change. The objectives of the present work were to relate
the physiological development of seeds and seed quality to recognisable
morphological stages of pod development and to relate this to
harvesting treatment.
MATERIALS AND METHODS:
Field experiments were carried out at Terrington St. Clements,
Norfolk, England (52o 45' N: 0o15' W) during
July and August 1995. Laboratory tests were carried out at The
Official Seed Testing Station for Scotland, East Craigs, Edinburgh.
A 0.8 hectare crop of Lotus corniculatus was sown in 1991,
at a seed rate of 3.5 kg of seed per hectare at 45 cm between
furrows. Paraquat® and Linacil®
were applied during spring for weed control. The crop was grown
from wild populations collected in the British isles to produce
seed for natural habitat reconstruction. Experiments on reserve
accumulation: Pods were collected at each stage of development
in five replications taken from five random sites marked in the
field. The stages of development were defined as follows:1- Purple-green
pod colour, shorter than 2 cm.2- Green pod colour , longer than
2 cm and thicker than 1 mm, green seed.3- Yellow pod, turning
to light brown in colour, green- light brown seed.4- Dry, brown
pod colour, brown seed. After collection, pods were put in air-water
proof plastic bags, and stored at -20 oC prior to laboratory
studies. Laboratory studies involved opening the pods and removing
four sets of 50 seeds from each replicate at each stage of development.
The sub samples were weighed and dried in oven following ISTA
rules for moisture content (Seed Science and Technology, 1993)
. The following indices were calculated for each stage of development:
-1000 seed weight at harvest moisture content;- Moisture content
at harvest;- 1000 seed weight of dried seed.
Experiments on post harvest maturation: After pollination and
during the different stages of seed development, five replicates
of 200 pods were harvested from each of the sites described above
in three different ways as follows: Treatment 1 (t1)- Direct harvest
and threshing with a commercial combine, a HEGE 125b, with the
cylinder speed set at 1043 rpm and with cylinder-concave set as
small as possible (less than 0.5 cm). Treatment 2 (t2)- Picking
pods from the plants, drying and threshing them after drying as
in t1. Treatment 3 (t3)- Cutting entire plants and drying them.
Seeds were threshed after drying as above. These different harvesting
methods were applied at all the stages of development described
above, with the exception of the first one, where the seeds were
not physically big enough to be threshed by a combine. For all
the treatments, seed, pods or plants were dried on trays inside
a green house for at least one week. Plant material in the trays
was covered with paper to avoid direct exposure to sun. The average
temperature reached was 25oC with a maximum of 38oC
and a minimum of 12oC. The relative humidity of the
air varied between 40% and 60% Germination tests: Germination
tests were carried out according to ISTA rules (Seed Science and
Technology, 1993). Four replications of 100 seeds were counted
for each stage of development and harvesting treatment. The seed
was set to germinate on top of paper (Whatman 181) at 20/30oC.
The first count was made at 7 days and the second at 12 days.
Germinated, hard, abnormal, dead and fresh seeds were recorded.
RESULTS
All results were subject to analysis of variance using the GENSTAT program.
Reserve accumulation: Results are shown in table 1.
| Table 1: Development of moisture content, dry weight and fresh seed weight in Lotus corniculatus. | |||
Water content showed a decline through the stages of development
as shown in Table 1. The maximum fresh seed weight was reached
at stage 3, which represents a light yellow-brown pod. Dry seed
weight also changed drastically from stage 2 to stage 3, going
form 0.47 to 1.56 gr. per 1000 seeds.
Post harvest maturation.
Germination tests: The results from the germination test were classified into the following categories:
a) Normal seedling after 12 days.
b) Hard seeds: after 12 days at 20/30oC.
c) Normal seedlings plus abnormal seedlings
d)Total germination: This is the germination value of a seed lot
as assessed in an official germination test and includes normal
seedlings plus hard and fresh seeds. The results can be seen in
Figures 1 and 2 as the addition of normal, hard and fresh seeds.
A significant difference in amount of normal seedling and in amount
of hard seeds with P< 0.001 was found between stages of development
and harvesting treatment. Total germination value showed significant
differences between harvesting treatments, stages of development
and the interaction between treatments and stages (P< 0.01).Normal
plus abnormal seedling were scored to find any possible differential
mechanical damage in any treatment. No difference was found neither
in harvesting treatment nor stage of development for both crops.
The overall amount of abnormal seed recorded was 4.4% The proportion
of normal seedling, fresh seeds, hard seeds and total germination
are presented in Figures 1 and 2 according to stage of development
and harvesting treatment respectively.
Figure 1: Development of normal seedling, hard seed, fresh seed and total germination (addition) at different stages of development in Lotus corniculatus. Standard error bars are displayed for total germination value.
Figure 2: Amount of normal seedling, hard seed, fresh seed and
total germination (addition) at different harvesting treatment
in Lotus corniculatus. Standard error bars are displayed
for total germination value.
| Table 2: Total germination value in Lotus corniculatus at different combinations of harvesting treatment and stage of development. LSD = 6.5 for P=0.05 | |||
A significant effect of the harvesting treatment was found (P<
0.01). As shown in Figure 2, the direct combining treatment presented
the lowest germination rate, and both harvesting treatment 2 and
3 presented the highest quality without significant difference
between them. The harvesting treatment 3 showed some pods attacked
by a weevil that was identified as Apion loti. It was present
in plants picked from the field and attacked some pods during
the drying process decreasing the final quality of seed. That
could be the reason of a lower trend in the germination of seed
from dried plants. The higher germination rate in harvesting treatment
3 is mainly due to a higher amount of hard seeds (Figure 2), while
in the case of harvesting treatment 2 it is due to higher number
of normal seedling. A similar trend in development of germination
through the stages of pod development was found. Seed collected
from green pods showed an extremely low germination rate of 5.1%
, rising to 57.8% in seed from light yellow-brown pods and up
to 86.7 % in seed from brown pods. A significant difference was
also found in the interaction between harvesting treatment and
stage of development (P< 0.01). As shown in table 2 seed did
not tolerate direct combining during stage 3 but germination increased
dramatically at the same stage when seed were dried in pods or
with the entire plant. It also shows that after this stage and
treatment the germination value seems to reach a maximum between
80% and 90%.
DISCUSSION
According to Bewley and Black (1994) seed grows from a single
fertilised egg to a multicellular embryo by cell division and
differentiation. These events are marked by a period of rapid
increase in whole seed fresh weight and water content. A period
of rapid gain in dry weight then follows as a result of the synthesis
and deposition of stored reserves. The whole seed fresh weight
then remains relatively stable, although the seed loses water
as this is displaced by the accumulation of insoluble reserves
within the cells of storage tissues. The evolution of water content
shown in Table 1 is as expected in seeds during accumulation of
reserves. It seems that the very early stages of embryo development,
where amount of water content increases has been missed, which
means it happens before the first stage of development studied.
Bewley and Black (1994) also described that the decline in water
content of a developing seed slows as it approaches its maximum
dry weight. Finally as the seed undergoes maturation drying and
approaches the quiescent stage, when it may be shed from the plant,
there is a period of fresh weight loss accompanied by a rapid
decline in whole seed water content. The fact that there is a
sharp drop in water content going from 59% to 17% between the
last two stages seems to indicate that the desiccation occurs
in Lotus corniculatus at the transition from light yellow
to brown colour. Winch and MacDonald (1961) reported similar trend
for pods, in this case pod moisture content fell from 65% to 25%
when changing to light brown colour. A slightly higher moisture
content was reported by Anderson (1955) who stated that seed become
morphologically mature at the time pods have light brown colour,
having a moisture content of 35% to 40%.However, Seaney and Henson
(1970) suggest that seed become physiologically mature slightly
before pods change colour from green to light brown, which corresponds
in this case to the transition from stage 2 to stage 3. This might
indicate that seeds increase in fresh and dry matter content even
after physiological maturation as will be discussed ahead. Hare
and Lucas (1984) defined the development stages in Lotus
as: a) growing stage, b) food reserve accumulation stage and c)
the ripening stage, counting days from pollination to classify
these stages. In this experiment the evolution of dry matter content
and water content seems to indicate that the transition from stage
2 (green pods) to stage 3 (light yellow-brown) could be the beginning
of the food reserve accumulation stage, meanwhile the transition
from stage 3 to stage 4 (brown colour) could be the ripening one.
Post harvest maturation. As explained in results he higher germination
rate in the harvesting treatment 3 is mainly due to a higher amount
of hard seeds (Figure 2), while in the case of harvesting treatment
2 it is due to higher number of normal seedling. These results
also indicates that some post harvest maturation occurs in a different
way according to the drying environment. Bewley and Black (1994)
state that hardseedness is a common feature in the Leguminosae
family and is a kind of dormancy in which water entry is the limiting
factor for germination. They also state that the testa is generally
responsible for impeding water uptake through different structures
like the waxy cuticle, suberin or the thick-walled palisade cells.
Which of these anatomical structures are able to be changed during
the last stages of development or during different conditions
of drying has not been studied in this paper. It could be worth
more research in the matter since the understanding of this maturation
process can have implications in commercial seed production. The
trend in total germination value found at different stages of
development is as expected. However, Anderson (1955) working in
Iowa found higher germination rate during the green pod stage,
reaching 90 % with the sum of normal and hard seeds. It is not
known whether these differences in physiological maturity are
due to a genetic effect or due to a year difference. The small
drop in germination value in dried plants during the stage of
light yellow-brown pods could be explained by the Apion loti
attack. Hare and Lucas (1984) stated that Lotus pedunculatus
reached seed maturity at the time pods were light-brown yellowish
colour, at this stage seed had 65% moisture content. This stage
correspond with stage 3 in this experiment in which maximum germination
was still not reached even if seed had the same moisture content.
The results of the interaction between harvesting treatment and
stage of development also agree with Hare and Lucas (1984) who
recommended, as mentioned above, that mowing should start at light
brown colour stage. The differences shown in table 2, could be
important for commercial seed production and opens a field for
more research. If technology allowed a mechanised way of picking
pods from the field as early as the light-yellow brown pod stage
and drying artificially, harvesting could start in an earlier
stage of maturation, before dehiscence in field. If dehiscence
happens in-building it will not mean seed loses. During seed drying
in the harvesting treatment 2 and 3 no dehiscence of pods was
noticed in all the stages of development, but as mentioned above,
temperature reached an average of 25oC with variation
in relative humidity between 40% and 60%. Metcalfe et al. (1957)
mentioned that in the Midwest and Northeast U.S.A. seed losses
from pod shattering can be high when relative humidity drops below
40%. Similarly, Phillips and Keim (1968) found 35% of relative
humidity as the point where pods start a rapid dehiscence. Under
different climatic situations it is not sure that mowing the crop
and allowing it to dry in the field in an earlier stage would
have not dehiscence of pods.
BIBLIOGRAPHY:
Anderson S.R. (1955) Development of pods and seed of birdsfoot trefoil (Lotus corniculatus L.) as related to viability and to seed yield. Agronomy Journal 47: 483-487.
Bewley, J.D and Black, M. (1994) Seeds, Physiology of development and germination. Second edition. Plenum press, New York and London.
Buckovic, R.G. (1952). MSc. Thesis. Oregon State College, Corvallis, Oregon.
Callen, E.O. (1959) Studies of the genus Lotus. Canadian Journal of Botany 37: 157-165.
Formoso, F. (1983). Effect of defoliation in Lotus corniculatus. Lotus Newsletter 14: 3.
Gardner, C.A. and Elliot, H.G. (1945) West Australia Dep. Agr. J. 22: 358-360.
Hare, M.D. and Lucas, R.J. (1984). `Grassland Maku lotus (Lotus pedunculatus L.) seed production. Journal of Applied Seed Production 2: 58-64.
McGraw, R.L. and Beuselinck, P.R. (1983) Growth and seed yield characteristics of birdsfoot trefoil. Agronomy Journal 75: 443-446.
Metcalfe, D.S., Johnson, I.J. and Shaw, R.H. (1957). The relationship between pod dehiscence, relative humidity and moisture equilibrium in birdsfoot trefoil (Lotus corniculatus L.). Agronomy Journal 49: 130-134.
Orsi, S. (1953). Ann. Ente. Consor Interprov. Tosc. Sementa IV, 30.
Panikar, M.R.(1949). Indian Farming 10: 444-447.
Phillips, R.L. and Keim, W.F. (1968). Seed pod dehiscence in Lotus and interspecific hybridisation involving L. corniculatus L. Crop Science 8: 18-21.
Pieroni, S.J. (1992) Factors affecting seed yield and quality in temperate forage legumes. MSc Thesis. The Edinburgh School of Agriculture. University of Edinburgh.
Robinson, D.H. (1934) Birdsfoot trefoil in Agriculture. Empire J. Exp. Agr. 2: 274-283.
Seaney, R.R. and Henson, P.R. (1970). Birdsfoot trefoil. Advances in Agronomy 22: 119-157.
Seed Science and Technology (1993). V 21 Supplement Rules. International Rules for Seed testing.
Wheeler, W.A. and Hill, D.D. (1957). Seed formation and germination. In Grassland seeds. Eds. Wheeler, W.A. and Hill, D.D. London, D. Van Nostrand Company, Inc. pp 12-34.
Winch, J.E. and MacDonald, H.A. (1961). Flower pod and seed development relative to the timing of the seed harvest of Viking birdsfoot trefoil (Lotus corniculatus L.) Canadian Journal of Plant Science 41: 523-532.
1. Error in title of paper:
"A chromosome atlas and interspecific-intergenic index
for Lotus and Tetragonolobus (Fabaceae). Can. J.
Bot. 73: 1787-1809, 1995.
The correct title is:
A chromosome atlas and interspecific-intergeneric index
for Lotus and Tetragonolobus (Fabaceae).
2. Error in Table 1 in the list of species
studied:
"Genome relationships among Lotus species based on
random amplified polymorphic DNA (RAPD)" by L. P. Campos,
J. V. Raelson and W. F. Grant. Theor. Appl. Genet. 88: 417-422,
1994.
Table 1 lists the species and their chromosome
numbers studied. Accession B-557 listed as L. japonicus,
2n = 12, is incorrect. Accession B-557 is L. corniculatus
and the chromosome number is 2n = 24.
The greatest number of Lotus species are those with a basic
chromosome number of 7 (x = 7). Evolutionarily, these species
are considered to be the oldest. This group is followed by those
species which have a basic chromosome number of x = 6. Only a
single species has a basic chromosome number of 5 (L. glareosus).
Chromosome evolution in the genus is considered to be occurring
by means of a reduction in the basic number from x = 7 to x =
6 to x = 5, in a descending aneuploid series from an eight-chromosomed
ancestor of the tribe Galegeae (Senn, 1938). In the new world
only a reduction from x = 7 to x = 6 has taken place to date (Grant
1995). The question arises as to how this reduction in basic number
came about?
Chromosome measurements were made representing three European
species. A drawing of the chromosomes for Lotus strictus
(previously unpublished) was used for the 7-chromosome species.
Idiograms of the species L. glacialis (2n = 12) and L.
glareosus (2n = 10) are given in the paper of Fernandes and
Queiros (1980) and chromosome measurements were made from these
idiograms for these two species. From the measurements for all
three species, idiograms were drawn using the chromosome analysis
package CHROMPAC III (Green et al. 1984).
The data from the chromosome analyses are given in Table I. The
idiograms in Figures 1 and 2 are photocopied from Fernandes and
Queiros (1980). Figs. 3-5 represent the idiograms based on the
detailed measurements. Satellites were not included in the measurements
of chromosome length.
| Karyotype measurements for Lotus strictus, L. glacialis and L. glareosus | |||||||
| L. strictus | |||||||
| L. glacialis | |||||||
| L. glareosus | |||||||
*Ratio: Long arm (p) divided by short arm (q)
Type: M, chromosome with centromere in median position; SM, submedian;
ST, subterminal
Index: p/p+q
Fernandes and Queiros (1980) have shown 2 pairs of satellited chromosomes on the short arms in both L. glacialis (chromosomes B and D) and L. glareosus (chromosomes B and C) (Figs. 1-2). Although chromosome B is the longest chromosome in L. glacialis, the authors have drawn this chromosome as the second chromosome of the complement (reason unknown) rather than the first. In contrast, no satellited chromosomes were observed in any of the metaphases examined for L. strictus (Fig. 3).
The computer program drew the chromosomes in descending length.
Chromosome B in Fig. 1 becomes chromosome 1 in Fig. 4. As may
be seen from Figs. 3-5, chromosome 1, for all three species, is
morphologically similar with submedian to subterminal centromeres.
Fernandes and Queiros (1980) pointed out the similarity of chromosomes
C and D between L. glacialis and L. glareosus in
Figs. 1 and 2. They explained the reduction in chromosome number
from n = 6 to n = 5 on non-separation of the chromatids during
anaphase as they observed metaphase plates in root tip cells of
L. glacialis (2n = 12) with 13, 11, and 10 chromosomes,
in addition to the normal complement of 12. One restitution cell
would lack chromosome F (Fig. 1) giving rise to L. glareosus
(Fig. 2) lacking this chromosome. They considered chromosome F
to be largely heterochromatic and therefore dispensable which
lead to the development of a species with a reduced chromosome
number (L. glareosus). They also suggested that L. glareosus
was derived from L. glacialis by chromosome rearrangements,
but the actual mechanism and chromosomes involved were not specified.
Chromosomes 2 and 3 in L. strictus are also very similar
to those of chromosomes 3 and 4 in both L. glacialis and
L. glareosus. A translocation between chromosomes 4 and 5
in L. strictus would give a largely median chromosome as
is chromosome 5 in L. glacialis. The loss of chromosome
7 in L. strictus by being either genetically inert or through
missegregation in mitosis would reduce the number to 2n = 12.
Similarly, a translocation between chromosomes 1 and 2 in L.
glacialis could produce chromosome 2 in L. glareosus
. With the loss of chromosome 5, L. glareosus would result
with the reduced chromosome number. By the classical translocation
route, a reduction in basic chromosome number could have taken
place as hypothesized above. However, observations in which chromosome
irregularities occur in both root tips of somatic (Fernandes and
Queiros 1980; O'Donoughue and Grant 1989), and meiotic cells (Somaroo
and Grant 1972) and in Lotus hybrids (O'Donoughue and Grant
1988) with the subsequent development of plants with stable chromosome
numbers would be an alternate explanation for the initiation of
plants with a reduction in basic chromosome number.
Fernandes, A. and Queiros, M. 1980. Sur l'occurrence de la pseudo- reduction somatique chez Lotus glacialis (Boiss.) Pau. Bol. Soc. Brot., Ser. 2, 54: 133-152.
Grant, W. F. 1995. A chromosome atlas and interspecific - intergeneric index for Lotus and Tetragonolobus (Fabaceae). Can. J. Bot. 73: 1787-1809.
Green, D. M., Myers, P. Z. and Renya, D. L. 1984. CHROMPAC III: an improved package for microcomputer-assisted analysis of karyotypes. J. Hered. 75: 143.
O'Donoughue, L. S. and Grant, W. F. l988. New sources of indehiscence for birdsfoot trefoil (Lotus corniculatus, Fabaceae) produced by interspecific hybridization. Genome, 30: 459- 468.
O'Donoughue, L. S. and Grant, W. F. 1989. Chromosomal variation in Lotus alpinus (Fabaceae). Plant Species Biol. 4: 117-122.
Senn, H. A., 1938. Chromosome numbers in the Leguminosae. Bibliograph. Genet. 12: 175-336.
Somaroo, B. H. and Grant, W. F. 1972. Chromosome differentiation
in diploid species of Lotus (Leguminosae). Theor. Appl.
Genet. 42: 34-40.
INTRODUCTION
In the New World, the genus Lotus L. comprises approximately
40 species distributed from British Columbia to Mexico in North
America. Only one species is endemic to Chile in South America.
L. salsuginosus Greene and L. salsuginosus var.
brevivexillus Ottley; L. strigosus (Nuttall) Greene,
L. strigosus var. hirtellus (Greene) Ottley,
and L. strigosus var. tomentellus (Greene) Isely,
are found in California, Lower California and Mexico, and in the
islands west of Lower California.
Nuttall (1838) treated L. strigosus as belonging
to genus Hosackia Bentham ex Lindley. Greene (1890), examined
and included Nuttall's species into the genus Lotus L.
He named L. tomentellus to one species from Lower California.
Ottley (1923) considered L. salsuginosus and L. strigosus
into the subgenus Acmispon Rafinesque. Later, Ottley (1944)
segregated the species belonging to Acmispon into two sections.
The section Microlotus Benth. (6 species) containing L.
salsuginosus and its variety, and the section Simpeteria
Ottley (12 species) containing L. strigosus, L. strigosus var.
hirtellus, and L. tomentellus. Isely (1981) reduced
L. tomentellus to a variety of L. strigosus.
Until present, the standard with blade attenuated into the claw,
the wings asymmetrically positioned and longer than the keel,
and the stigma penicillate, are the characters used to separate
the section Simpeteria from the section Microlotus.
However, these characters and those (e. g., density of the pubescence,
presence and shape of the bract, standard shapes) used to separate
L. salsuginosus and L. strigosus are not enough
to delimitate L. salsuginosus var. brevivexillus
and L. strigosus var. tomentellus. These are two
varieties of different species frequently confused.
The purpose of this article is to emphasize the most useful characters,
and to include news, to delimitate L. salsuginosus var.
brevivexillus and L. strigosus var. tomentellus.
MATERIALS AND METHODS
Specimens of herbarium, fruit and seed samples surveyed, were
from BRY, MEXU, NSMC, SD, US. The acronyms for the herbaria are
given according to Holmgren et al. (1990). Some samples were from
Desert Legume Program, Tucson (UAz). Morphological and anatomical
characters were examined with a stereoscopic microscope (at 40
x or less) and an optical microscope; both equipped with a camera
lucid. The testa topographic features were analysed on whole seeds
and portions of them mounted on brass-stubs, sputter-coated with
gold-palladium in a JFC-1100 and viewed at 15 kv with a Jeol JSM-T100
scanning electron microscope (SEM). The topographic features were
described according to Lersten (1981). Drawings of the characters
were prepared by the author.
L. salsuginosus (Greene) Greene
L. salsuginosus Greene var. brevivexillus Ottley
Lotus strigosus (Nutt.) Greene var. tomentellus Isely
Comment
(*) specimens mounted on the same sheet.
(**) the specimens on the sheet correspond to L. strigosus
var. tomentelllus, whereas the material into the envelope
attached, contains a mixture of the specimen with L. salsuginosus
var. brevivexillus.
Results and Discussion
| Table 1. Corolla, legume and seed characteristics to distinguish L. salsuginosus Greene var. brevivexillus Ottley and L. strigosus (Nutt.) Greene var. tomentellus Isely. | ||
| L. salsuginosus var. brevivexillus | L. strigosus var. tomentellus | |
| COROLLA | (Fig. 1, A-C-E) | (Fig. 1, B-D-F) |
| Standard venation | The veins show a curved course in the base of the blade. | The veins show a ± straight course in the base of the blade. |
| Wing | The auricle is always exposed | The auricle is obscured by the upper margin folded downwards. |
| Keel | The upper margin straight. The apex obtuse. | The upper margin convex or slightly so. The apex acute. |
| LEGUME | (Fig. 1, G) | (Fig. 1, H) |
| The hard and persistent base of the style always recurved | The hard and persistent base of the style always short and straight. | |
| SEED | (Fig. 2, A-a) | (Fig. 2, B-b) | (Fig. 2, C) | (Fig. 2, D) |
| Seed shape | globose | globose | globose | laterally compressed |
| Seed shape in outline (Face view) | ovate-round | quadrangular to round | circular | circular, rarely quadrangular |
| Testa surface(At 40 x or less) | smooth | smooth or near so | rugose | sinuate rugose |
| Radicular lobe | inconspicuous | discernible | discernible | prominent |
| Lens | small mound | small mound | conspicuous | conspicuous |
| Hilum elevation | superficial | superficial | superficial | sunken in lateral notch |
| Hilar rim | conspicuously discoloured | concoloured | concoloured | concoloured |
| Micropyle | bifurcate | bifurcate | bifurcate | deltoid |
| Testa topography, on mid-face | papillose (small papillaes) | reticulate | reticulate sinuate or non sinuate, with mounds | papillose sinuate, with or without very small mounds |
Acknowledgments
I wish thank to the staff of the institutions who supplied the
specimens and fruit-seed samples studied. My special thank to
Mario Sousa S. and Maru García Peńa who borrowed
most of the specimens studied. Thank Liliana Katinas for providing
a number of suggestions that helped to improve earlier manuscripts
and Rafael Urrejola for technical assistance using SEM.
REFERENCES
Greene, E. L. 1890. Enumeration of the North American Loti. Pittonia 2: 133-150.
Holmgren, P. K. , N. H. Holmgren and L. C. Barnett. 1990. Index Herbariorum. P. 1. The Herbaria of the World. [Regnum Veg. 120]. NY Bot. Gard., Bronx.
Isely , D. 1981. Leguminosae of the United States. III. Subfamily Papilionoideae: Tribes Sophoreae, Podalyrieae, Loteae. Mem. NY Bot. Gard. 29(3): 124-264.
Lersten, N. R. 1981. Testa Topography in Leguminosae, Subfamily Papilionoideae. Proc. Iowa Acad. Sci. 88(4): 180-191.
Ottley, A. M. 1923. A revision of the Californian species of Lotus. Univ. California Publ. Bot. 10: 189-305.
Ottley, A. M. 1944. The American Loti with special consideration of a proposed new section, Simpeteria. Brittonia 5(2): 81-123.
In our laboratory, all combinations of somatic
cell hybrids have been carried out among a graminous plant, rice
(Oryza sativa L.) and three leguminous plants, soybean
(Glycine max (L.) MERR.), birdsfoot trefoil (Lotus corniculatus
L.) and alfalfa (Medicago sativa L.). We report here asymmetric
somatic hybrid of birdsfoot trefoil and alfalfa.
Materials and Methods
The calli of birdsfoot trefoil cv. Viking
and alfalfa cv. Rangelander were used for the isolation of protoplasts.
The enzyme solution for the protoplast isolation of both birdsfoot
trefoil and alfalfa was constituted with 4% Cellulase Onozuka
RS, 1% Macerozyme R-10, 0.2% Pectolyase Y-23 and 0.6 or 0.7 M
mannitol. The division of birdsfoot trefoil protoplasts was inhibited
by the treatment of 10 mM iodoacetamid (IOA). The protoplasts
of alfalfa were irradiated by 40 kR of X-rays. The fused protoplasts
were then cultured in the KM8p medium (Kao and Michayluk, 1975)
by the agarose-beeds and nurse culture methods. The isozymes of
obtained calli and regenerated shoots were examined on aminopeptidase
(AMP), esterase (EST), glutamate dehydrogenase (GDH) and catalase
(CAT).
Results and Discussion
The 155 callus lines were obtained from the
asymmetrc somatic cell fusion of birdsfoot trefoil and alfalfa.
Among these calli, 17 callus lines were identified as somatic
cell hybrids by the analyses of isozymes (Table 1). After one
month of subculture, most of the hybrid calli, however, altered
the isozyme banding patterns to those of birdsfoot trefoil on
the medium of Murashige and Skoog (1962) (MS medium) with 4 mg/l
1-naphthaleneacetic acid (NAA) and 2.5 mg/l kinetin or with 1.5
mg/l indole-3-acetic acid (IAA) and 1.5 mg/l 6-benzyladenine (BA).
This result means that most of the alfalfa chromosomes irradiated
by X-rays disappeared during the subcultures. Niizeki et al. (1989)
reported that the shoot regeneration did not occur from the symmetric
somatic hybrid calli of birdsfoot trefoil and alfalfa. On the
other hand, in this study shoot regeneration occurred from the
asymmetric somatic cell hybrid calli. All isozyme banding patterns
of these shoots investigated so far, however, were the same as
those of birdsfoot trefoil. These results show that it is possible
to regenerate the shoots from the cybrid calli derived from the
asymmetric hybrid in which donor protoplasts irradiated by X-rays,
while it seems to be impossible to regenerate the shoots from
the symmtrical somatic hybrids which have both parent chromosomes.
This phenomenon was also observed in the somatic cell hybrid of
birdsfoot trefoil and soybean (Niizeki et al. 1990, 1994).
| Table 1. Isozyme analyses of asymmetrical somatic cell hybrids of alfalfa and birdsfoot trefoil. | |||||||||||||
| Total colonies obtained by protoplast fusion = 155.
Number of obtained hybrid clones = 17. | |||||||||||||
| Hybrid clone | Plant regeneration | ||||||||||||
| I-1 | |||||||||||||
| I-3 | |||||||||||||
| I-7 | |||||||||||||
| I-16 | |||||||||||||
| I-20 | |||||||||||||
| I-27 | |||||||||||||
| I-29 | |||||||||||||
| I-31 | |||||||||||||
| I-78 | |||||||||||||
| I-82 | |||||||||||||
| II-14 | |||||||||||||
| II-34 | |||||||||||||
| II-44 | |||||||||||||
| II-45 | |||||||||||||
| II-46 | |||||||||||||
| II-47 | |||||||||||||
| II-63 | |||||||||||||
* : +, plant regeneration; -, no plant regeneration.
Isozyme pattern A: Investigate the calli cultured for one month;
Isozyme pattern B: Investigate the calli cultured for two months;
Isozyme pattern C: Investigate the regenerated plant.
A: Isozyme band pattern of alfalfa; B: Isozyme band pattern of
birdsfoot trefoil; A+B: Isozyme band pattern of both parents.
References
Kao, K.M. and M.R.Michayluk 1975. Nutritional requirements for growth of Vicia hajastana cells and protoplasts at a very low population density in liquid media. Planta 126: 105-110.
Murashige, T. and F. Skoog 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant 15: 473-497.
Niizeki, M. and K. Saito 1989. Callus formation from protoplast fusion between leguminous species of Medicago sativa L. and Lotus corniculatus L. Japan. J. Breed. 39: 373-377.
Niizeki, M., K. Kihara and K-N. Cai 1994. Somatic hybridization between birdsfoot trefoil (Lotus corniculatus L.) and soybean (Glycine max L.). In Biotechnology in Agriculture and Forestry, Vol.27 "Somatic Hybridization in Crop Improvement I", Y.P.S. Bajaj (ed), Springer-Verlag pp132-144.
Niizeki, M., K. Cai, M. Kihara, S. Nakajo and T. Harada 1990. Somatic cell hybrids between birdsfoot trefoil and soybean. Lotus Newslett. 21: 14-17.
A morphological and architectural study was made on an herbaceous species of Fabaceae, Lotus tenuis Walds. et Kit (narrow birds-foot trefoil), a perennial pasture legume.
This species was introduced into South America (in Argentina, in 1930), from Europe, and became established and naturalized on the Flooding Pampa (Burkart, 1952). Agronomists are selecting various commercial varieties for best performance an alternative to Medicago sativa (lucerne grass) affected by flooding, a very common disturbance in this region (León and Oesterheld, 1982).
This research represents a basic study of the morphology and growth habit of Lotus tenuis, that is essential for a correct grazing management.
The study was conducted during 1993-94, seeds sown in May 17,
at experimental fields of the Faculty of Agronomy, Buenos Aires,
Argentine,(34ş 35'S, 58ş 29'W), with seeds from a cultivar
provided by AgroVerónica, Verónica, Buenos Aires
Province. Twenty isolated plants were sampled to determined the
architectural unit before nature defoliation.
The architectural unit of any plant are the different (morphological and functional) axes categories (Barthélémy, 1991). These axes are formed by shoot-units (Bell, 1994), each derived from one apical meristem.
The architectural unit is determined by two shoot categories: vegetative and reproductive (flowering branches). The leaves have spiral arrangement and have a single axillary bud with 2 prophylls (&) each with a bud, which can develop vegetative or reproductive branches. The first branches (prb) develop from the prophyllar buds of the axillary complex. Sometimes only one of the prophyllar bud develops, whilst the another and the axillary bud, remain dormant.
The vegetative shoots are basitonic. All vegetative axes -main
axis (ma) and branches (b)- are monopodial with continuous growth
. Shoot units initially develop horizontally, then change growth
direction and procede to develop vertically (Fig. 1 A-D). The
proximal nodes of the shoot units have the capacity to produce
adventitious roots (ar), this represents a plagiotropic form during
establishment (Fig. 1 C-D). The converse reorientation occurs
once for the initial shoot unit of many herbaceous plants (Bell,
1994).
The apical meristematic activity is limited, when the growing season finishes in summer after flowering (Fig 1 C & D), all the apical meristems die (md).
During the first year the plant develops the crown, formed by a group of closed branches arising at the basal nodes of the main axis, first and second order branches, near the soil (Fig. 1 B-D).
The reproductive branching pattern is acrotonic (Fig. 1 C). The
flowering branches (fb) arise from the axillary buds of the upper
nodes of all vegetative axes.
The architecture (growth-form, habit) is determined by one orthotropic, sympodial axis (ma), with limited growth; orthotropic basitonic vegetative branches with a similar pattern (reiterations) occur (Fig. 1 D).
The plant repeats its elementary architecture (the architectural unit, building by shoot units).
At the end of growing season, when the shoots units of the previous year die, the proximal nodes lateral buds of the plagiotropic phase of the branches (Fig. 1 D) give rise new reiterations -proleptic, partial and adaptive- (nr). The old dead stems, of previous year, with adventitious roots, remain as stolons or rhizomes. These regrowth shoots may be vulnerable to damage by too-intensive grazing. The importance of the plagiotropic development of the basal shoots is crucial to long lived axillary meristems.
The independence of the different modules from the main axes may
develop, as an important way of propagation, in the second or
third period of growth, although it's not clear, the importance
of this strategy, during the establishment.
The architectural model responds to Tomlinson's. Shoot units initially
develop horizontally, then change growth direction, in established
phase as in the Tomlinson's model (Hallé, et al., 1978).
References.
Barthélémy D. 1991. Levels of organization and repetition phenomena. Acta Biotheoretica 39: 309-323.
Bell AD. 1994. A Summary of the Branching Process in Plants. In Ingram, D.S. & Hudson, A. (eds.), Shape and Form in Plants and Fungi. Linn. Soc. Symposium Series 16, pp. 119-142. London: Academic Press.
Burkart A. 1952. Las Leguminosas argentinas silvestres y cultivadas.Ed. ACME, Bs. As. 2da. Edición. Pp.590.
Hallé F, Oldeman RAA & Tomlinson PB. 1978. Tropical trees and forests. Springer, Berlín. Pp. 441.
León RJC y Oesterheld M. 1982. Envejecimiento de pasturas implantadas en el Norte de la Depresión del Salado, un enfoque sucesional. Rev.Fac. Agron. Bs. As. 3: 41-49.
:
Lotus tenuis A-E; diagrammatic representation of 5 growing stages: A.- First stage: The main axis bears at the cotyledonary node, one shoot with a prophyllar branch, at each cotyledon axil; all the axes show continuous growth; B.-Second stage : Main axis with basitonic continuous branches from cotyledons to 4-node. The prophyllar branches are larger than cotyledonary shoots; C.- Third stage: Adult phase previous to reproductive stage with complete branching pattern (second and third order branches); D.- Fourth stage: Adult phase with flowering branches; E.- Last stage: Apical meristem of all shoots die. The reiterations (broken line) arise from the crown.
Arrows indicate that stems are still growing. In C all the axes with curved arrows indicate a larger growth than the main axis. In B & C Stars and asterisks represented second order branches. Cotyledons are represented schematically and are not to scale; normal foliage leaves are not represented. In D, little stars represent second order flowering branch.
Abbreviations: ar: adventitious roots; b1, b2, b3 and b4: first node axillary branch to four node branch; c: cotyledon; cs: cotyledonary shoot; fb: flowering branches, ma: main axis; md: meristem death; prb: prophyllar branch; re: reiterations.
Arrows indicate that stems are still growing. Stars represent second order flowering branch. Cotyledons are represented schematically and are not to scale; normal foliage leaves are not represented.
Isolation, chemical structures and biological activity of the
lipo-chitin oligosaccharide nodulation signals from Rhizobium
etli. Cardenas, L.; Dominguez, J.; Quinto, C.; Lopez-Lara,
I. M.; Lugtenberg, B. J. J.; Spaink, H. P.; Rademaker, G. J.;
Haverkamp, J.; Thomas-Oates, J. E. Departamento de Biologia Molecular
de Plantas, Instituto de Biotecnologia, Universidad Nacional Autonoma
de Mexico, Mexico. Plant Molecular Biology vol. 29 (3): p.453-464.
Publication Year: 1995
Rhizobium etli is a microsymbiont of plants of the genus
Phaseolus. Using MS the lipo-chitin oligosaccharides (LCOs)
that are produced by R. etli strain CE3 were identified.
They are N-acetylglucosamine pentasaccharides of which the nonreducing
residue is n-methylated and n-acylated with cis-vaccenic acid
(C18:1) or stearic acid (C18:0) and carries a carbamoyl group
at C4. The reducing residue is substituted at the C6 position
with O-acetylfucose. Analysis of their biological activity on
the host plant Phaseolus vulgaris shows that these
LCOs can elicit the formation of nodule primordia which develop
to the stage where vascular bundles are formed. The formation
of complete nodule structures, including an organized vascular
tissue, is never observed. Considering the close resemblance of
the R. etli LCO structure of those of R. loti, the
ability of R. etli strains to nodulate various Lotus
species and of R. loti to nodulate P.vulgaris was
tested. The results show that R. etli is able to nodulate
Lotus plants. However, several Lotus species are
only nodulated when an additional flavonoid independent transcription
activator (FITA) nodD gene is provided. Phaseolus plants
can also be nodulated by R. loti bacteria, but only when
the bacteria contain a FITA nodD gene. Apparently, the type of
nod gene inducers secreted by the plants is the major basis for
the separation of Phaseolus and Lotus into different
cross inoculation groups.
A chromosome atlas and interspecific-intergenic index for Lotus
and Tetragonolobus (Fabaceae). Grant, W. F. Department
of Plant Science, P.O. Box 4000, McGill University, Macdonald
Campus, Ste Anne de Bellevue, QC H9X 3V9, Canada. Canadian Journal
of Botany vol. 73 (11): p.1787-1809 Publication Year: 1995
Basic chromosome numbers in Lotus are x = 5, 6 and 7. It
is considered that evolution has proceeded in the genus by means
of a descending aneuploid series from an 8-chromosomed ancestor.
Chromosome numbers for species of Tetragonolobus are based
on x = 7. Somatic chromosome markers are reported for 108 species
and 38 varieties. Chromosome numbers are reported for the first
time for 5 species (L. hamatus, L. haydonii, L. hintoniorum,
L. mearnsii and L. utahensis; all 2n = 14), 6 varieties (L.
argophyllus var. argenteus, L. dendroideus var.
traskiae, L. heermanii var. orbicularis, L. junceus var.
biolettii, L. strigosus var. hirtellus, L. strigosus var.
tomentellus; all 2n = 14) and L. uliginosus subsp.
vestitus (2n = 12). Natural diploid, tetraploid and hexaploid
plants are reported for L. alpinus. Several species are
reported as possessing B chromosomes. Mixoploidy is reported to
occur in L. alpinus, L. glacialis and L. glareosus.
In addition, chromosome numbers are given for plants regenerated
from calluses grown in tissue culture having heteroploidy, euploidy
and mixoploidy. Root nodules are reported with tetraploid and
octoploid cells in addition to the normal number of chromosomes.
Trisomic series have been partially developed in L. tenuis
and L. uliginosus. Polytene chromosomes were observed in
suspensor cells of three species of Lotus. Feulgen cytophotometric
measurements, to determine the DNA nuclear content, were made
for 16 species of Lotus and one species of Tetragonolobus.
The majority of the studies in Lotus concerned the economic
species L. corniculatus, L. tenuis and L. uliginosus.
Interspecific hybridization was carried out in different combinations
between diploids, autoploids and amphidiploids. Intergeneric hybrids
were attempted by somatic hybridization, protoplast fusion and
assymetric hybridization between Lotus and other species
(Glycine max, Medicago sativa, Oryza sativa).
Effect of inoculation and nitrate on nitrate reductase activity
and acetylene reduction activity in Lotus sp.- Rhizobium
loti symbiosis. Diaz, P.; Borsani, O.; Monza, J. Departamento
de Bioquimica, Facultad de Agronomia, Av. E. Garzon 780 C.P. 12900,
Montevideo, Uruguay. Symbiosis (Rehovot) vol. 19 (1): p.53-63.
Publication Year: 1995
The effects of nitrate and the Rhizobium strain used in
the inoculation on acetylene reduction activity (ARA), nitrate
reductase activity (NRA) and nitrate concentration in tissues
of two Lotus species inoculated with different Rhizobium
loti strains were examined. ARA in the symbiosis Lotus
corniculatus-R. loti T1 strain was inhibited 90% by nitrate
compared with 36% in the L. tenuis-R. loti Y3 symbiosis.
NRA in leaves and nitrate concentration in stems were modified
by inoculation. L. tenuis and L. corniculatus nodulated
by R. loti T1 strain had lower nitrate concentration in
the stem than when the same plants were nodulated by R. loti
Y3 and U226 strains and the non-nodulated plants. Inoculation
increased the NRA expression in leaf tissues of Lotus spp.
nodulated by R. loti T1 strain and the nitrate concentration
was similar to that found in non-nodulated plants.
Forage halophytes in the Mediterranean basin. Le Houerou,
H. N. 327 rue A. L. De Jussieu, 34090 Montpellier, France. Book
Title: Halophytes and biosaline agriculture. p.115-136. Publication
Year: 1995. Editors: Choukr-Allah, R.; Malcolm, C. V.; Hamdy,
A. Publisher: Marcel Dekker Inc. New York, USA ISBN: 0-8247-9664-0
It was shown that out of 700 Mediterranean halophyte species,
27.5% were from the Chenopodiaceae, 15% from the Poaceae, 6% from
the Asteraceae and 5% from the Caryophyllaceae, Fabaceae and Zygophyllaceae;
70% were perennial and 30% annual or biennial. The most common
tree species was Tamarix, the most common shrubs Salicornia,
Salsola, Suaeda and Atriplex, the most common perennials
Aeluropus, Sporobolus, Puccinellia and the most common
annual species Hordeum maritimum, Lepturus cylindricus, Frankenia
and Melilotus. The halophytic vegetation was described
and aspects of the palatability (ratio of feed intake:fodder on
offer) and preference; primary productivity (aboveground biomass
of Atriplex halimus was 10-15 t DM/ha and annual productivity
2-5 t DM/ha); grazing and nutritive value (digestible DM 40-70%,
digestible OM 50% and CP content 10-12%); and cultivation (Atriplex
nummularia, A. semibaccata and Myoporum insulare grown
in Australia and A. canescens and A. lentiformis
in the USA) were discussed. Many salt tolerant fodder species
used in land reclamation with or without irrigation using saline
water (Festuca arundinacea, Sporobolus, Trifolium fragiferum,
Lotus corniculatus, Lolium rigidum, Hordeum vulgare, Melilotus
alba, M. italica and Medicago spp.) gave DM yields
of 5-20 and 2-10 t/ha, respectively.
Comparison of conventional and alternative nursery weed management
strategies. Calkins, J. B.; Swanson, B. T. Dept. Hort. Sci.,
Univ. Minn., St. Paul, MN 55108, USA. Weed Technology vol. 9 (4):
p.761-767. Publication Year: 1995 ISSN: 0890-037X
In a field plot at the University of Minnesota, St. Paul, soil
cultivation (3 to 5 times/yr) and herbicide management (oxadiazon,
3.92 kg ai/ha), agricultural standards for reducing weed competition,
were compared to 3 alternative nursery field management systems
regarding weed suppression: 'Norcen' bird's-foot trefoil (Lotus
corniculatus) companion crop, 'Wheeler' winter rye cover crop/mulch
and grass sod (80% 'Eton' perennial ryegrass (Lolium perenne)
and 20% 'Ruby' red fescue (Festuca rubra)). Field management
treatment had a significant effect on observed weed populations.
Weed densities were also subject to yearly variations caused by
climate and endogenous weed life cycles. Herbicide management
(oxadiazon) consistently provided the best control of undesired
vegetation (0.3 weeds/m2) followed by the grass sod (0.7 weeds/m2),
Wheeler rye cover crop/mulch (1.7 weeds/m2), Norcen bird's-foot
trefoil companion crop (8.6 weeds/m2), and cultivated (55.7 weeds/m2)
treatments. Although the grass sod treatment provided excellent
control of undesired vegetation, as an alternative to cultivation
and herbicide use, it proved to be excessively competitive with
the nursery crop. The bird's-foot trefoil treatment quickly became
infested with broadleaf weeds the eradication of which proved
difficult. The Wheeler winter rye cover crop/mulch field management
system provided acceptable weed control combined with other beneficial
effects on the plant/soil environment. Results support the effectiveness
of Wheeler winter rye and perhaps other allelopathic cover crop/mulch
systems in controlling undesired vegetation in horticultural field
production systems.
Meiosis and seed production in plants of different populations
of birdsfoot trefoil (Lotus corniculatus L.). Nikolaichuk,
V. I. Uzhgorod University, Uzhgorod, Ukraine. Tsitologiya i Genetika
vol. 29 (4): p.61-66. Publication Year: 1995 ISSN: 0564-3783
PMC meiosis was studied in 3 natural populations and 4 varieties.
The frequency of disturbances at different stages of meiosis was
low, not exceeding 12.5% at the tetrad stage in the variety Smolens'kii.
Plants of this variety had the lowest pollen fertility and, accordingly,
the lowest seed set.
Rhizomatous Lotus corniculatus L.: I. Taxonomic and
cytological study. Beuselinck, P. R.; Li, B.; Steiner, J.
J. USDA-ARS, Plant Genetics Research Unit, Columbia, MO 65211,
USA. Crop Science vol. 36 (1): p.179-185. Publication Year: 1996
ISSN: 0011-183X
Wild, putative L. corniculatus accessions from Morocco
differ distinctly from domesticated L. corniculatus in
that they produce rhizomes. Rhizomes may be useful in increasing
stand persistence of domesticated L. corniculatus. The
objective of this study was to identify to the species level the
wild Lotus accessions from Morocco (G31272, G31273, G31276,
G31298 and G31317) that present rhizomatous growth. Comparative
morphological and cytological analyses, and intercrossing with
L. corniculatus, were used in this study. Six morphological
characters that distinguish L. corniculatus and L. uliginosus
(the only species in the genus Lotus recognized as producing
rhizomes) were used to categorize taxonomically the Moroccan accessions.
The Moroccan accessions were morphologically similar to L.
corniculatus with the exception of the rhizome trait. The
accessions were tetraploid with 2n = 4x = 24 somatic chromosomes.
Karyotype analyses detected more similarities than differences
between the Moroccan accessions and Norcen. Progeny were produced
from intercrosses between L. corniculatus cultivars Norcen
and AU Dewey and the Moroccan accessions. Hybridity of progeny
was verified by morphological and RAPD analyses. A sample of reciprocal
F1 progeny were tetraploid, fertile and consistent in their production
of rhizomes. A combination of morphological, chromosome, and karyotype
analyses confirmed accessions G31272, G31273, G31276, G31298,
and G31317 as L. corniculatus. This is the first description
of L. corniculatus with rhizomes.
Proanthocyanidins from Lotus corniculatus. Foo,
L. Y.; Newman, R.; Waghorn, G.; McNabb, W. C.; Ulyatt, M. J. NZ
Institute for Industrial Resesarch and Development, P.O. Box 31-310,
Lower Hutt, New Zealand. Phytochemistry vol. 41 (2): p.617-624.
Publication Year: 1996 ISSN: 0031-9422
The chemical structure of the purified proanthocyanidin polymers
of Lotus corniculatus was analysed by 13C NMR and by mild
acid catalysed degradation in the presence of excess of phloroglucinol.
The NMR data showed that the polymer was partially glycosidated
with a number average MW in the range 1800-2100 (6 to 7 flavanoid
units). The products from phloroglucinol scission reaction indicated
the extender flavan units to consist mostly of epicatechin (67%)
and epigallocatechin (30%), with minor amounts of catechin and
epiafzelechin units, which were linked together predominantly
by C-4/C-8 interflavanoid bonds. The polymer chains were terminated
mostly by catechin (83%) and, to a lesser extent, by epicatechin
(16%).
Taproot tip penetration and young seedling growth in relation
to root-hair adhesion among surface-sown legume species. Morita,
O.; Iwabuchi, K.; Goto, M.; Ehara, H. Faculty of Bioresources,
Mie University, Tsu, Mie 514, Japan. Nippon Sochi Gakkaishi =
Journal of Japanese Society of Grassland Science vol. 40 (4):
p.437-442. Publication Year: 1995 ISSN: 0447-5933
Seeds of white clover (Trifolium repens), alsike clover
(T. hybridum), red clover (T. pratense), crimson
clover (T. incarnatum), birdsfoot trefoil (Lotus corniculatus),
alfalfa (Medicago sativa) and common vetch (Vicia sativa)
were surface-sown on yellow soil under controlled conditions with
25 deg C and 100% RH. Penetration percentage of taproot tips,
mean days for taproot penetration, and hypocotyl and root growth
of three adhesion types in germination behaviour were examined
for five days to decide the adhering function of taproot hairs.
The three adhesion types in legumes were contact-adhesion, partial-adhesion
and non-adhesion, depending on the degree of adhesion in the taproot
hairs. Ninety percent of taproot tips of the contact-adhesion
type in white clover, alsike clover, birdsfoot trefoil and alfalfa
penetrated into the soil, being significantly higher than that
of partial-adhesion type. The same tendency was observed in red
clover, crimson clover and common vetch. The mean time for taproot
tip penetration of the contact-adhesion type was shorter than
that of the partial-adhesion type in all species examined. Length
and proportion of taproot exposed on the soil surface were shorter
in the contact-adhesion type than in the partial-adhesion type.
The hypocotyl-root ratio in length was highest in the contact-adhesion
type, followed by partial-adhesion type and non-adhesion types.
Therefore, good adhesion of taproot hairs to the surface enhanced
the hypocotyl growth as compared with taproot growth, and poor
adhesion of taproot hairs enhanced taproot growth. It is suggested
that the contact-adhesion type of germination behaviour would
provide good establishment compared with partial-adhesion and
non-adhesion types.
Effect of adhesion of taproot hairs to the soil surface on
germination behaviour in surface-sown legume species. Morita,
O.; Iwabuchi, K.; Goto, M.; Ehara, H. Faculty of Bioresources,
Mie University, Tsu, Mie 514, Japan. Nippon Sochi Gakkaishi =
Journal of Japanese Society of Grassland Science vol. 40 (4):
p.429-436. Publication Year: 1995 ISSN: 0447-5933
White clover (Trifolium repens), alsike clover (T. hybridum),
red clover (T. pratense), crimson clover (T. incarnatum),
birdsfoot trefoil (Lotus corniculatus), alfalfa (Medicago
sativa), and common vetch (Vicia sativa) were sown
on the surface of yellow paddy field soil under controlled conditions
at 25 deg C and 100% RH. Some morphological characteristics of
the taproot in relation to germination behaviour were measured.
Elongating taproots pushed the seed backwards and grew without
penetration of their tips into the soil. After root hairs developing
on taproots adhered to the surface, anchoring the seedlings, root
tips penetrated into the soil. Germination behaviour was classified
into three types: (i) taproot hairs that developed initially adhered
to the soil surface, thus taproots grew in contact with the soil
surface and root tips penetrated into the soil (contact-adhesion
type); (ii) taproot hairs adhered partially to the soil surface,
a part of the taproot was not in contact with the surface, but
root tips penetrated (partial-adhesion type); and (iii) taproot
hairs failed to adhere to the surface, taproots were not in contact
with the soil, and failed to penetrate into the soil (non-adhesion
type). White clover and birdsfoot trefoil had a higher percentage
of the contact-adhesion type in germination. Alsike clover, red
clover, crimson clover and alfalfa had higher percentages of the
partial-adhesion type, and common vetch had a higher percentage
of the non-adhesion type. The percentage of contact-adhesion type
seedlings was related to the ratio between length of root hair
and root diameter in the legume species. The adhering area that
was bound on the soil surface by taproot hairs was significantly
larger in the contact-adhesion type than in the partial-adhesion
type. It is suggested that an adhering function of taproot hairs
in surface-sown legume seedlings may secure good penetration of
root tips before establishment can be achieved.
Novel and complex chromosomal arrangement of Rhizobium loti
nodulation genes. Scott, D. B.; Young, C. A.; Collins-Emerson,
J. M.; Terzaghi, E. A.; Rockman, E. S.; Lewis, P. E.; Pankhurst,
C. E. Molecular Genetics Unit, Department of Microbiology and
Genetics, Massey University, Palmerston North, New Zealand. Molecular
Plant-Microbe Interactions vol. 9 (3): p.187-197. Publication
Year: 1996 ISSN: 0894-0282
A mutational and structural analysis of Rhizobium loti
nodulation genes in strs NZP2037 and NZP2213 was carried out.
Unlike the case with other Rhizobium strs examined to date,
nodB was found on an operon separate from nodACIJ. Sequence analysis
of the nodACIJ and nodB operon regions confirm that R. loti
common nod genes have a gene organization different from that
of other Rhizobium spp. At least 4 copies of nodD-like
sequences were identified in R. loti. The complete nucleotide
sequence of one of these, nodD3, was determined. A new host-specific
nod gene, nolL, was identified adjacent to nodD3. NolL shares
homology NodX and other O-acetyl transferases. Mutational analysis
of the nod regions of strains NZP2037 and NZP2213 showed that
nodD3, nodI, nodJ, and nolL were all essential for R. loti
strs to effectively nodulate the extended host Lotus pedunculatus,
but were not necessary for effective nodulation of the less restrictive
host, Lotus corniculatus. Both nodD3 and nolL were essential
for R. loti strs to nodulate Leucaena leucocephala.
Evaluation and characterization of Lotus corniculatus
accessions in spaced and dense stand conditions. (Valutazione
e caratterizzazione di accessioni di Lotus corniculatus
a piante spaziate e a semina fitta.) Negri, V.; Francia, U.;
Veronesi, F. Istituto di Miglioramento Genetico Vegetale, Universita
degli Studi, Perugia, Italy. Rivista di Agronomia vol. 29 (2):
p.160-164. Publication Year: 1995 ISSN: 0035-6034
In forage plants, single plant evaluation is often reported to
be of little interest in predicting sward performance. With the
aim of assessing the reliability of spaced plant evaluation in
screening birdsfoot trefoil germplasm for breeding purposes, a
spaced plant trial and a dense stand trial were set up. Nine natural
populations were studied in both trials. The following agronomic,
physiological and qualitative characters were recorded in 1993:
winter growth, spring regrowth, first flower date, average stem
length, total dry matter yield, crude protein, crude fibre, ash,
in vitro dry matter digestibility, milk feeding units and meat
feeding units. Polcanto, Macerata and Canetra were the most promising
natural populations. The data collected for each character and
for each population in the spaced plant and dense stand trials
showed substantial agreement. When screening birdsfoot trefoil
accessions from sites with different ecological conditions, evaluation
of spaced plants appears to be reliable in predicting sward performance.
Use of herbicides for the chemical protection of non-traditional
forage crop seed stands. (Vyuziti herbicidu v chemicke ochrane
semenarskych porostu netradicnich picnin.) Tesar, O. Vyzkumny
Ustav Picninarsky, 664 41 Troubsko, Czech Republic. Scientific
Studies - Research Institute for Fodder Plants (No. 13): p.91-104.
Publication Year: 1995
One pre-sowing and 14 post-em. herbicides were compared in seed
crops of the annual forage legumes Melilotus albus, Trigonella
coerulea, Tetragonolobus purpureus, Lotus ornithopodioides and
Malva verticillata in 1993 and 1994. The most effective combinations
were imazethapyr-ammonium + pyridate + rapeseed oil in T. coerulea
and M. albus with yield increases, no phytotoxicity and
95.7-100% control of Amaranthus sp. and 67.8-71.5% control
of Chenopodium sp. In M. verticillata, metamitron
+ triclopyr, metamitron + phenmedipham or desmedipham, and metamitron
+ fluazifop-P-butyl or haloxyfop gave 72.1-90.7% weed control
without phytotoxicity but crop yields were unaffected. T. purpureus
and L. ornithopodioides trials were unsatisfactory.
Seed multiplication of alpine grasses and herbs. (Saatgutvermehrung
alpiner Graser und Krauter.) Krautzer, B. Bundesanstalt fur
Alpenlandische Landwirtschaft Gumpenstein, 8952 Irdning, Austria.
Rasen-Turf-Gazon vol. 26 (4): p.123-131. Publication Year: 1995
ISSN: 0341-9789
Short descriptions are given of 7 grasses, 4 legumes and 6 forbs
regarded as promising for use in mixtures for resowing damaged
areas at high altitude and suitable for commercial seed production
at lower altitude. Information is presented on seed characteristics,
1000-seed weight, germination and seed quality. The latter was
comparable with that of commercial seed of lowland species. Seed
yields of Festuca nigrescens and Poa alpina decreased
with increasing altitude of origin, but adaptation to high altitude
may be more important than yield. In Trifolium pratense
subsp. nivale the disease susceptibility of some strains
meant that their yield was not related to the altitude of origin.
Average seed yields of the grasses (F. nigrescens, F. pseudodura,
F. supina (F. airoides), F. violacea, Phleum alpinum,
P. hirsutum and Poa alpina) were 100-500 kg/ha and
those of the legumes (Anthyllis vulneraria, Lotus corniculatus,
Trifolium badium and T. pratense subsp. nivale)
were 30-350 kg/ha. The highest yielding forb was Dianthus superbus
(average 578 kg/ha); the other species (Arnica montana, Crepis
aurea, Leontodon hispidus, Melandrium rubrum and Plantago
montana) yielded 100-300 kg/ha. Potential yields were considerably
higher. Trials of mixtures and sowing techniques for specific
areas are continuing.
Steps toward defining the role of lectins in nodule development
in legumes. Hirsch, A. M.; Brill, L. M.; Lim, P. O.; Scambray,
J.; Rhijn, P. van Department of Molecular, Cell and Developmental
Biology, 405 Hilgard Avenue, University of California, Los Angeles,
CA 90095-1606, USA. Conference Title: 10th International congress
on nitrogen fixation, St. Petersburg, Russia, 28 May-3 June 1995.
Symbiosis (Rehovot) vol. 19 (2/3): p.155-173. Publication Year:
1995 ISSN: 0334-5114
A number of plant and bacterial genes are specifically induced
upon the interaction between rhizobia and plants during the onset
of nodulation. However, many other genes such as those encoding
lectin, a protein which has been hypothesized as being involved
in host recognition by rhizobia, are not specifically induced
in response either to rhizobial inoculation or to Nod factor treatment.
Exactly how lectin is involved in recognition between rhizobia
and legume is still not well understood. To this end, two lucerne
lectin genes were isolated and characterized from a lucerne genomic
library. Lectin mRNA-antisense lucerne plants were generated and
the early stages of development of transgenic plants were studied.
Differences were seen from the control plants with respect to
the number of plants formed per callus. Also, the soyabean lectin
gene was transferred into lucerne as well as Lotus corniculatus,
and the response of the transgenic plants to inoculation with
Bradyrhizobium japonicum, the usual symbiont for soyabean,
was examined.
Seed yield, size and indeterminacy in diverse accessions of
Lotus corniculatus L. grown in the UK. Bullard, M.
J.; Crawford, T. J Department of Biology, University of York,
Heslington, York YO1 5DD, UK. Plant Varieties & Seeds vol.
9 (1): p.21-28. Publication Year: 1996 ISSN: 0952-3863
Eighteen accessions of the forage legume Lotus corniculatus
were grown as spaced plants. The period of mature seed production,
number of seed pods, seed yield and seed size of these accessions
were measured. All accessions produced mature seed over a period
of at least 8 weeks. The pattern of production varied greatly
between accessions and included unimodal, bimodal and irregular
forms. A common date for peak of seed pod production could not
be ascertained. There was no indication that any variety or UK
ruderal alien exhibited a more contracted period of pod production
that could be exploited in a plant breeding programme. The 100-seed
weights of the different accessions varied two-fold (between 116.2
and 239.7 mg); ecotypes were generally heavier than varieties
or alien accessions. The Norwegian ecotype from Nigardelen had
heavier seed than any other accession, and as seedling vigour
is positively correlated with seed size in L. corniculatus,
it may offer potential for improvement of seed size in commercial
material by interaccessional crossing.
The influence of diet on growth and secretion behaviour of
myrmecophilous Polyommatus icarus caterpillars (Lepidoptera:
Lycaenidae). Burghardt, F.; Fiedler, K. Lehrstuhl Zoologie
II, Theodor-Boveri-Biozentrum der Universitat, Am Hubland, D-97074
Wurzburg, Germany. Ecological Entomology vol. 21 (1): p.1-8. Publication
Year: 1996 ISSN: 0307-6946
Larvae of the facultatively myrmecophilus lycaenid Polyommatus
icarus were reared on inflorescences, or foliage, of 4 natural
hostplant species and on an artificial diet to study dietary effects
on larval growth and secretory capacity. Larvae achieved highest
weights and relative growth rates when fed flowers of Medicago
sativa (lucerne), Lotus corniculatus or Melilotus
officinalis. Larvae reared on Coronilla varia (flowers
and leaves), foliage of M. sativa and on the artificial
diet pupated at lower weights and achieved lower growth rates.
In standardized experiments with the ant species Lasius flavus,
secretion rates from the dorsal nectar organ (DNO) were 2 times
higher among flower-fed larvae than among foliage-fed siblings
or larvae on the artificial diet. Larvae reared on C. varia
flowers were superior to all other food treatments with respect
to secretion rates. High water content of larval diet, as in flowers
appears to be important for lycaenid larvae to achieve high secretion
rates, whereas the correlation between myrmecophily and nutrient
availability, as evidenced by growth rates, was less pronounced.
Using experimental data on larval growth and secretion rates,
the lifetime volume of secretions from the DNO was estimated to
range from 2 to 5 micro l in most food treatments. Only on C.
varia flowers (5.5-8.7 micro l) and on M. sativa leaves
(0.0-1.1 micro l) did the larvae deviate in their absolute investment
in myrmecophily. The estimated lifetime investment accounted for
1.6-5.5% of prepupal fresh weight in all food treatments except
on C. varia flowers (7.8-12.3%).
How much fertilizer will a species-rich chalk grassland in
the Swabian Alb stand? (Wieviel Dungung 'vertragt' ein artenreicher
Kalkmagerrasen der Schwabischen Alb?) Briemle, G. Staatliche
Lehr- und Versuchsanstalt fur Viehhaltung und Grunlandwirtschaft
(LVA), Atzenbergerweg 99, 88326 Aulendorf, Germany. Kongressband
1995 Garmisch-Partenkirchen. Vortrage zum Generalthema des 107.
VDLUFA-Kongresses vom 18.-23.9.1994 in Garmisch-Partenkirchen:
Grunland als Produktionsstandort und Landschaftselement. Conference
Title: Kongressband 1995 Garmisch-Partenkirchen. Vortrage zum
Generalthema des 107. VDLUFA-Kongresses vom 18.-23.9.1994 in Garmisch-Partenkirchen:
Grunland als Produktionsstandort und Landschaftselement. p.631-634
Publication Year: 1995. Publisher: VDLUFA-Verlag Darmstadt, Germany
ISBN: 3-922712-55-X
In 1983-93 dry chalk grassland at 780 m alt. dominated by Bromus
erectus, Sanguisorba minor, Lotus corniculatus and Trifolium
montanum and containing many species of gentians and orchids
was mown in July each year and given 20 kg N + 20 kg P + 32 kg
K/ha, half these rates, 10 kg P + 16 kg K or no fertilizer, was
mulched or the succession was left undisturbed. Mineral fertilizer
application or mulching had little effect on the number of species
present, which remained at 60-70/25 m2. The number of species
fell by about 19% on the other plots. The herbage cut in July
contained 10.8% CP and consisted of 44% grasses, 8% legumes and
48% other forbs. Average DM yields ranged from 2.3 t/ha with no
fertilizer to 3.1 t with the higher NPK rate. The hay was highly
acceptable to growing cattle and gave liveweight gains of 990
g/d.
Drought stress in seedlings: lipid metabolism and lipid peroxidation
during recovery from drought in Lotus corniculatus and
Cerastium fontanum. Olsson, M.; Nilsson, K.; Liljenberg,
C.; Hendry, G. A. F. Dept. of Plant Physiology, Univ. of Goteborg,
Carl Skottsbergs gata 22, S-413 19 Goteborg, Sweden. Physiologia
Plantarum vol. 96 (4): p.577-584. Publication Year: 1996 ISSN:
0031-9317
Seedling survival of drought during the first days following germination
can be one of the most critical factors in successful establishment
of the species. 72-h-old seedlings of Cerastium fontanum and
Lotus corniculatus were exposed to severe desiccation for
36 h and the recovery of the whole plants monitored over the subsequent
17 d. The analysis exposed the very different responses to water
stress in the two species. The effects of water stress on the
less drought tolerant L. corniculatus within the first
5 to 10 d after drought treatment included a 2-fold larger loss
in dry weight than in C. fontanum and a 2-fold rise in
lipid peroxidation (thiobarbituric acid-reactive substances),
in triacylglycerols and in free fatty acids. The ratio of monogalactosyl
diacylglycerols/digalactosyl diacylglycerols (MGDG/DGDG) declined
3-fold, while the proportion of MGDG was some 12-fold lower. In
contrast, in the relatively drought-tolerant seedlings of C.
fontanum no changes of this order were recorded in the days
immediately following rehydration. The relationship between these
changes in lipid metabolism, lipid peroxidation and drought-induced
damage in terms of growth is discussed in the context of seedling
recovery and survival in the two species.
Cotyledon and leaf development associated with seedling vigor
of six forage legumes. Hur, S. N.; Nelson, C. J. Department
of Animal Science, Chonbuk National University, Chonju 560-756,
Korea Republic. Journal of the Korean Society of Grassland Science
vol. 15 (1): p.19-23. Publication Year: 1995 ISSN: 1013-9354
Seeds of Medicago sativa, Trifolium hybridum, T. pratense,
T. repens, Lotus corniculatus and Lespedeza striata
were sown in a silt loam, peat and sand mixture in pots and kept
in growth chambers. The cotyledons expanded rapidly in the 1st
week after emergence then slowly up to the 3rd week. Maximum cotyledon
areas of T. pratense, M. sativa, T. hybridum, T. repens and
L. corniculatus were 9.5, 6.5, 6.4, 6.3 and 4.5-fold larger,
respectively, than the mean area at emergence, whereas that of
L. striata was only 2.9-fold the size. Larger seeds produced greater
cotyledon areas and the rate of cotyledon expansion was positively
correlated with seedling vigour. The development of leaf area
followed a similar relationship. Early onset of leaf production
contributed, with early leaf production, to vigorous seedling
growth.
Cotyledon development and seedling growth of Lotus corniculatus,
Lotus tenuis and their reciprocal hybrids. Hur, S.
N.; Beuselinck, P. R.; Nelson, C. J. Department of Animal Science,
Chonbuk National University, Chonju 560-756, Korea. Journal of
the Korean Society of Grassland Science vol. 15 (1): p.13-18.
Publication Year: 1995 ISSN: 1013-9354
Seeds of Lotus corniculatus, L. tenuis and their reciprocal
hybrids were sown in pots in a silt loam, peat and sand mixture.
Cotyledon size was measured from seedling emergence to cotyledon
senescence at 2-day intervals. Seedlings were harvested 3 weeks
after emergence to measure net photosynthetic rate, dark respiration
rate and seedling dry weight. Cotyledons expanded rapidly during
the 1st week, then only slightly until maximum size was reached
3 weeks after emergence. Cotyledon area at emergence was positively
correlated with seed size but after emergence there was a divergence
in cotyledon expansion rate, with seed size alone not a reliable
indicator of seedling vigour. Rate of leaf area development was
a determinant of seedling growth. Some of the hybrids showed increased
seedling vigour compared with the parent species.
Element concentration cadasters of halophytic plant communities
in Hungary. Kovacs, M.; Penksza, K.; Turcsanyi, G.; Kaszab,
L.; Otvos, E. Agricultural University, Department of Botany and
Plant Physiology, H-2103 Godollo, Hungary. Acta Botanica Hungarica
vol. 39 (1/2): p.3-16. Publication Year: 1995 ISSN: 0236-6495
At Kiskunsag National Park species from the Lepidio-Camphorosmetum
annuae and Agrosti-Caricetum distantis plant communities
growing on solonchak soils were assessed and at Hortobagy National
Park species from the Camphorosmetum annuae and Artemisio-Festucetum
pseudovinae communities occurring on the solonchak-solonetz
soils were assessed. Soil samples from both sites were analysed.
Foliage of some of the halophytes (e.g. Camphorosma annua,
Lepidium cartilagineum, Lotus tenuis and Scorzonera parviflora)
contained high quantities of heavy metals. Monocots (including
Puccinellia distans and Festuca pseudovina) were
characterized by a smaller total content of detectable elements
as well as a smaller element concentration range (0.1-1000 micro
g/g) than the dicots. Tables are presented of soil element contents
and the element contents of the leaves and other plant organs
analysed.
Isolation, chemical structures and biological activity of the
lipo-chitin oligosaccharide nodulation signals from Rhizobium
etli. Cardenas, L; Dominguez, J.; Quinto, C.; Lopez-Lara,
I.M.; Lugtenberg, B.J.J.; Spaink, H.P.; Rademaker, G.J.; Haverkamp,
J.; Thomas-Oates, J.E. . Universidad Nacional Autonoma de Mexico.
Plant molecular biology. 1995. vol. 29 (3), p. 453-464.
Rhizobium etli is a microsymbiont of plants of the genus
Phaseolus. Using mass spectrometry we have identified the
lipo-chitin oligosaccharides (LCOs) that are produced by R.
etli strain CE3. They are N-acetylglucosamine pentasaccharides
of which the non-reducing residue is N-methylated and N-acylated
with cis-vaccenic acid (C18:1) or stearic acid (C18:0) and carries
a carbamoyl group at C4. The reducing residue is substituted at
the C6 position with O-acetylfucose. Analysis of their biological
activity on the host plant Phaseolus vulgaris shows that
these LCOs can elicit the formation of nodule primordia which
develop to the stage where vascular bundles are formed. The formation
of complete nodule structures, including an organized vascular
tissue, is never observed. Considering the very close resemblance
of the R. etli LCO structures to those of R. loti
(I. M. Lopez-Lara, J. D. J. van den Berg, J. E. Thomas Oates,
J. Glushka, B. J. J. Lugtenberg, H. P. Spaink, Mol Microbiol 15:
627-638, 1995) we tested the ability of R. etli strains
to nodulate various Lotus species and of R. loti
to nodulate P. vulgaris. The results show that R. etli
is indeed able to nodulate Lotus plants. However, several
Lotus species are only nodulated when an additional flavonoid
independent transcription activator (FITA) nodD gene is provided.
Phaseolus plants can also be nodulated by R. loti
bacteria, but only when the bacteria contain a FITA nods gene.
Apparently, the type of nod gene inducers secreted by the plants
is the major basis for the separation of Phaseolus and
Lotus into different cross inoculation groups.
Relative effectiveness of phosphorus on narrow-leaf and broadleaf
birdsfoot trefoil growth and the effect of added phosphorus on
vesicular arbuscular mycorrhizal infection. Mendoza, R.; Gigli,
S. Centro de Ecofisiologia Vegetal, Buenos Aires, Argentina..
Journal of plant nutrition. 1995. vol. 18 (7), p. 1483-1494.
The relative effectiveness of phosphorus (P) applications on growth
and the effect of added P on the extent of infection of roots
of narrowleaf birdsfoot trefoil (Lotus tenuis) and of broadleaf
birdsfoot trefoil (Lotus corniculatus) by an indigenous
VAM fungi (Glomus sp.) was studied on a P-deficient soil
(Typic Natraquoll). In terms of rate of increase of shoot growth
per unit of added P, broadleaf was more efficient than narrowleaf
birdsfoot trefoil but they did not differ in the relative effectiveness
of P for growth. For the two Lotus species, when increasing
the level of added P there was an initial increase in the percentage
of root length infected, and then with further additions, there
was a consistent decrease of the infection. For narrowleaf, the
maximum percentage of root length infected was when plants reached
11% of their maximum shoot growth. Whereas for broadfleaf, the
maximum percentage of root infected was when plants reached the
66% of their maximum shoot growth. Despite differences in both,
the shape of the response curve of shoot growth to P and the extent
of infection between d species, they did not differ in their ability
to utilize the P that had reacted with the soil for a period of
time.
Evaluation of a phytotoxin(s) from Pseudomonas syringae
for weed control in cranberries. Norman, M.A.; Patten,
K.D.; Gurusiddaiah, S. Washington State University, Long Beach,
WA. HortScience. 1994. vol. 29 (12), p. 1475-1477.
Three indicator species [rye (Secale cereale L.), radish
(Raphanus sativus L.), and alfalfa (Medicago sativa
L.)] and nonrooted cuttings of 'Stevens' cranberry (Vaccinium
macrocarpon Ait.) vines were grown in pots to establish the
dose response levels for a sand-applied phytotoxin(s) from a crude
extract of Pseudomonas syringae (strain 3366) culture.
At 114 ppm [milligrams phytotoxin(s)/kilograms sand], the material
was noninhibitory, whereas 1140 ppm reduced root and shoot growth
significantly in all four species. In subsequent experiments,
a 10-ppm dose controlled corn spurry (Spergula arvensis
L.) and fireweed (Epilobium angustifolium L.) seedlings,
while 103 ppm reduced root or shoot growth of cuttings of the
perennial weeds birdsfoot trefoil (Lotus corniculatus L.)
and silverleaf (Potentilla pacifica Howell). Root and shoot
growth of partially rooted 'McFarlin' cranberry vines was reduced
at 103 and 563 ppm, respectively. The phytotoxin(s) could potentially
control germinating annual weeds in newly established 'Stevens'
cranberry bogs.
Novel and complex chromosomal arrangement of Rhizobium loti
nodulation genes. Scott, D.B.; Young, C.A.; Collins-Emerson,
J.M.; Terzaghi, E.A.; Rockman, E.S.; Lewis, P.E.; Pankhurst, C.E.
Massey University, Palmerston North, New Zealand. Molecular plant-microbe
interactions. 1996. vol. 9 (3), p.187-197.
A mutational and structural analysis of Rhizobium loti
nodulation genes in strains NZP2037 and NZP2213 was carried out.
Unlike the case with other Rhizobium strains examined to
date, nodB was found on an operon separate from nodACIJ. Sequence
analysis of the nodACIJ and nodB operon regions confirm that R.
loti common nod genes have a gene organization different from
that of other Rhizobium spp. At least 4 copies of nodD-like
sequences were identified in R. loti. The complete nucleotide
sequence of one of these, nodD3, was determined. A new host-specific
nod gene, nolL, was identified adjacent to nodD3. NolL shares
homology with NodX and other O-acetyl transferases. Mutational
analysis of the nod regions of strains NZP2037 and NZP2213 showed
that nodD3, nodI, nodJ, and nolL were all essential for R.
loti strains to effectively nodulate the extended host Lotus
pedunculatus, but were not necessary for effective nodulation
of the less restrictive host, Lotus corniculatus. Both nodD3 and
nolL were essential for R. loti strains to nodulate Leucaena
leucocephala.
Molecular cloning and characterisation of asparagine synthetase
from Lotus japonicus: dynamics of asparagine synthesis
in N-sufficient conditions. Waterhouse, R. N.; Smyth, A. J.;
Massonneau, A.; Prosser, I. M.; Clarkson, D. T. IACR-Long Ashton
Research Station, Department of Agricultural Sciences, University
of Bristol, Long Ashton, Bristol BS19 9AF, UK. Plant Molecular
Biology vol. 30 (5): p.883-897. Publication Year: 1996.
Two cDNA clones, LJAS1 and LJAS2, encoding different asparagine
synthetases (AS) (aspartate-ammonia ligase) have been identified
and sequenced and their expression in Lotus japonicus characterized.
Analysis of predicted amino acid sequences indicated a high level
of identity with other plant AS sequences. No other AS genes were
detected in the L. japonicus genome. LJAS1 gene expression
was found to be root-enhanced and lower levels of transcript were
also identified in photosynthetic tissues. In contrast, LJAS2
gene expression was root-specific. These patterns of AS gene expression
are different from those seen in pea. AS gene expression was monitored
throughout a 16 h light/8 h dark day, under nitrate-sufficient
conditions. Neither transcript showed the dark-enhanced accumulation
patterns previously reported for other plant AS genes. To evaluate
AS activity, the molecular dynamics of asparagine synthesis were
examined in vivo using 15N-ammonium labelling. A constant rate
of asparagine synthesis in the roots was observed. Asparagine
was the most predominant amino-component of the xylem sap and
became labelled at a slightly slower rate than the asparagine
in the roots, indicating that most root asparagine was located
in a cytoplasmic 'transport' pool rather than in a vacuolar 'storage'
pool. The steady-state mRNA levels and the 15N-labelling data
suggest that light regulation of AS gene expression is not a factor
controlling N-assimilation in L. japonicus roots during
stable growth in N-sufficient conditions. Nucleotide sequence
data have been submitted to the EMBL/GenBank/DDBJ databases under
the accession numbers X89409 (LJAS1) and X89410 (LJAS2).
Registration of GIFU B-129-S9 Lotus japonicus germplasm.
Stougaard, J.; Beuselinck, P. R. Department of Molecular Biology,
Aarhus University, Gustav Wiedsvej 10, DK-8000 Aarhus C, Denmark.
Crop Science vol. 36 (2): p.476. Publication Year: 1996
GIFU B129-S9 represents an S9 inbred derived from the GIFU accession
B129, the original source of which was collected near Gifu, Japan.
The growth form of mature GIFU B129-S9 plants is intermediate,
with multiple branches up to 30 cm long. Flowering is indeterminate.
Plants are cross-fertile, making classical genetic studies possible.
Fast-growing strains of Rhizobium loti and some slow-growing
strains of Bradyrhizobium spp. will nodulate GIFU B129-S9,
but R. loti strain NZP 2235 is recommended for fast and
effective nodulation.
Proposed ecological descriptors and their utility for plant
germplasm collections. Steiner, J. J.; Greene, S. L. National
Forage Seed Production Research Center, USDA-ARS, 3450 SW Campus
Way, Corvallis, OR 97331, USA. Crop Science vol. 36 (2): p.439-451.
Publication Year: 1996.
Plant germplasm collections are important repositories of genes
that ensure potentially useful sources of genetic variation are
preserved for future uses. Detailed information about genetic
differences among individuals or groups of accessions can be helpful
for management and utilization of germplasm collections. At present
a description of the collection site is required when collecting
accessions, but the kinds and amount of information recorded that
describe the natural environmental features of the collection
site may vary greatly depending on the collector. This paper discusses
the need for providing standardized and detailed ecological descriptors
for collected accessions that can be entered into the US National
Plant Germplasm System (NPGS) Germplasm Resources Information
Network (GRIN) database and provides a set of necessary tools
to accomplish this. Proposed in this paper are (i) a flexible
set of ecological descriptors that capture the most important
ecological features of the collection site and its environment
so that a standardized description can be given of the natural
conditions where accessions are found, (ii) a revised accession
data collection form that can be used to describe the natural
features of the collection site, and (iii) a method to retroclassify
poorly documented accessions that do not have detailed descriptions
of the collection site. The widely adapted perennial forage legume
birdsfoot trefoil (Lotus corniculatus) is used to demonstrate
the principles presented in this paper.
Rhizomatous Lotus corniculatus L.: II. Morphology and
anatomy of rhizomes. Li, B.; Beuselinck, P. R. Department
of Agronomy, University of Missouri, Columbia, MO, 65211, USA.
Crop Science vol. 36 (2): p.407-411. Publication Year: 1996.
Birdsfoot trefoil (Lotus corniculatus) is a valuable forage
legume. Rhizomatous L. corniculatus germplasm from Morocco
was recently discovered (accessions G31272, G31273, G31276, G31298
and G31317). Increased persistence may result from the rhizomatous
habit, because new plants vegetatively generated by rhizomes could
replace diseased or dead plants. Rhizome morphology in L. corniculatus
from Morocco is unique because taxonomic descriptions for L.
corniculatus do not include the presence of rhizomes. The
morphology and anatomy of subterranean lateral shoots (rhizomes)
and aerial shoots (stems) of these L. corniculatus accessions
were described and compared. Rhizomes of Moroccan L. corniculatus
are initiated from axillary buds on basal portions of shoots.
The rhizome consists of nodes and internodes, with buds, scale
leaves, and adventitious roots occurring at each node. Anatomically,
the rhizome of L. corniculatus has a large cortex, small pith,
and six to seven primary vascular bundles. No endodermis exists
in the cortex, and parenchyma cells contain starch. In contrast,
the aerial shoot of L. corniculatus has a small cortex,
large pith, and nine to 10 primary vascular bundles. An endodermoid
layer is peripheral to the concentric ring of vascular bundles
of the aerial shoot, and parenchyma cells in the cortex contain
chloroplasts. Morphological and anatomical differences between
L. corniculatus rhizomes and aerial shoots are distinguishable.
A simple technique for direct transformation and regeneration
of the diploid legume species Lotus japonicus. Oger,
P.; Petit, A.; Dessaux, Y. Institut des Sciences Vegetales, CNRS,
Batiment 23, Avenue de la Terrasse, F-91198, Gif-sur-Yvette, France.
Plant Science (Limerick) vol. 116 (2): p.159-168. Publication
Year: 1996.
The diploid legume species Lotus japonicus was transformed
using a disarmed Agrobacterium strain. By inoculating the
cotyledon attachment site, the regenerative capability of the
plant allowed spontaneously regenerated transformed shoots. Some
of these shoots were propagated as transgenic plants and later
transferred to the glasshouse to produce seeds. Seeds were germinated
and yielded non-chimaeric, transgenic stably modified Lotus
plants.
A system for tissue-specific copper-controllable gene expression
in transgenic plants: nodule-specific antisense of aspartate aminotransferase-P2.
Mett, V. L.; Podivinsky, E.; Tennant, A. M.; Lochhead, L.
P.; Jones, W.T.; Reynolds, P. H. S. Plant Improvement Division,
Horticulture and Food Research Institute of New Zealand, Private
Bag 11030, Palmerston North, New Zealand. Transgenic Research
vol. 5 (2): p.105-113. Publication Year: 1996.
A vector system, based on copper controllable gene expression,
has been developed to give control over place as well as time
of expression of an introduced gene. This system consists of two
elements: (1) the yeast ace1 gene encoding a metallo-regulatory
transcription factor, ACE1, under control of either an organ-specific
or a constitutive promoter; and (2) a gene of interest under control
of a chimaeric promoter consisting of the 46 bp TATA fragment
of the CaMV 35S RNA promoter linked to four repeats of the ACE1
binding site. The functioning of the system in an organ-specific
manner was tested in nodulated Lotus corniculatus plants
which consisted of non-transformed shoots plus transformed hairy
root tissue 'wild-type tops/transgenic roots'. After addition
of copper ions to the plant nutrient solution, beta -glucuronidase
(GUS) expression was visualized either specifically in nodules
or in both roots and nodules when the ace1 gene was placed under
control of the nod45 promoter or the CaMV 35S RNA promoter, respectively.
The nodule-specific system was used to express antisense constructs
of aspartate aminotransferase-P2 in transgenic Lotus corniculatus
plants. When expression was induced by the addition of copper
ions to the plant nutrient solution aspartate aminotransferase-P2
activity declined dramatically, and a decrease of up to 90% was
observed in nodule asparagine concentration.
Seasonality of mycorrhizae in coastal sand dunes of Baja California.
Siguenza, C.; Espejel, I.; Allen, E. B. Department of Botany and
Plant Sciences, University of California, Riverside, CA 92521-0124,
USA. Mycorrhiza vol. 6 (2): p.151-157. Publication Year: 1996.
Populations of arbuscular mycorrhizal fungi were estimated from
spores associated with 7 plant species in coastal dunes at El
Socorro, near Ensenada, Baja California, Mexico, during 6 months
in 1992. The seasonal patterns of percentage root colonization
were also described in the same species during the wet season
(Jan.-Mar.) and the dry season (Apr.-Jul.). Comparisons were made
between the pioneer species (Abronia maritima) in the mobile
dunes and 6 species (Abronia umbellata, Atriplex julacea,
Camissonia californica, Haplopappus venetus, Helianthus niveus
and Lotus spp.) in the fixed dunes. Mycorrhizal colonization
in Abronia maritima was slight (<1%) and few spores
(<1/g soil) were observed. All species in the fixed dune formed
mycorrhizae with up to 80% colonization in early summer, and no
more than 4 spores/g soil by late summer. The highest percentages
of total colonization and abundance of spores did not coincide
temporally for any of the 7 species, but the percentages were
higher in summer than in spring. Arbuscules were more abundant
when the soil was moist, and vesicles more abundant when it was
dry.
Selection for biological nitrogen fixation and nitrogen utilization
in birdsfoot trefoil. Ehlke, N. J.; Vellekson, D. J.; Lyman,
B. E. Department of Agronomy and Plant Genetics, University of
Minnesota, St. Paul, MN 55108, USA. Crop Science vol. 36 (1):
p.104-109. Publication Year: 1996.
Birdsfoot trefoil (Lotus corniculatus) is a perennial forage
legume which has a lower rate of biological nitrogen fixation
(BNF) than alfalfa (Medicago sativa). Studies were conducted
to evaluate the gain from two cycles of recurrent selection in
the glasshouse in three germplasms of birdsfoot trefoil (Norcen,
AU-Dewey and MU81) using traits associated with improved BNF or
N utilization. For improved BNF, selection was based on morphological
traits correlated with the acetylene reduction assay (ARA) in
a nil-N soil environment. For improved N utilization, selection
was based on increased top dry weight production in a N-rich soil
environment. The 12 selected populations and the three parental
populations were evaluated in two growth chambers in a completely
randomized design with four replicates. The chambers were watered
three times per week with 100 ml of a modified Hoagland's solution
containing either 0.0 (nil-N environment) or 10.7 (N-rich environment)
mM N. At 8 and 14 weeks after seeding, the plants were individually
scored for nodule mass and fibrous roots, top dry weight, ARA
rate, and N yield. Correlated trait selection for improved BNF,
as measured by the ARA, produced populations with larger plants,
more fibrous roots, and greater nodule mass resulting in a 56%
increase in ARA in the nil-N environment. In the N-rich environment,
the populations selected for improved BNF showed a significant
increase in nodule mass and a 79% increase in ARA rate. Selection
for improved N utilization resulted in larger plants with more
fibrous roots, larger nodule mass, higher N yield and a 77% increase
in ARA in the N-rich environment. In the nil-N environment, the
populations selected for improved N utilization had larger root
systems, slighter better nodulation, and produced larger plants
which resulted in a 58% increase in ARA rate. Correlated trait
selection for traits which support BNF or N utilization could
significantly improve the performance of birdsfoot trefoil in
environments with fluctuating N availability.
Estimation of the crude protein content in grass and legume
populations of the spontaneous flora using a chemical colorimetric
micromethod. Original Title: Estimarea continutului de proteina
bruta din populatiile de graminee si leguminoase din flora spontana
prin micrometode chimice colorimetrice. Drochioiu, G.; Avramiuc,
M.; Risca, I. M. Banca de Gene, Suceava, Romania. Cercetari Agronomice
in Moldova vol. 28 (1/2): p.45-50. Publication Year: 1995.
The crude protein contents of 18 populations of 9 grass spp.,
18 populations of 7 Trifolium spp. and 13 populations of
7 other legume spp. were estimated by the coloration of free amino
acids with a reagent containing ninhydrin. The intensity of the
coloration was proportional to their concentration and indirectly
to that of the protein content. This micromethod was rapid and
precise. Crude protein contents ranged from 9.84% in the Zamostea
population of Lolium perenne to 19.4% in the Poiana Stampei
2 population of Festuca rubra, from 13.32% in the Ponoare
population of Trifolium pannonicum to 25.69% in the Danila
population of T. repens and from 14.18% in the Ilisesti
population of Lotus corniculatus to 32.08% in the Danila
population of Vicia cracca.
Purification and characterization of vegetative storage proteins
from alfalfa (Medicago sativa L.) taproots. Cunningham,
S. M.; Volenec, J. J. Department of Agronomy, Purdue University,
West Lafayette, IN 47907-1150, USA. Journal of Plant Physiology
vol. 147 (6): p.625-632. Publication Year: 1996.
Alfalfa (Medicago sativa) accumulates C and N reserves
in taproots and utilizes these reserves for shoot growth in spring
and for shoot regrowth after defoliation. Three proteins are very
abundant in taproots and undergo a cyclic pattern of utilization
during early shoot growth followed by reaccumulation during late
shoot development. These putative vegetative storage proteins
were purified and characterized from alfalfa taproots. The proteins
were purified using organic-solvent and ionic-precipitation techniques,
gel filtration, and affinity chromatography. Polyclonal antibodies
were raised against the purified proteins, and electrophoresis
and immunoblotting were utilized to determine protein distribution
and relative abundance. These proteins are present in high concentrations
in alfalfa taproots, but were not found in seeds, nodules, leaves,
or stems of alfalfa. Taproots of all perennial Medicago
species examined contained these proteins, whereas roots of annual
Medicago species had very low to undetectable amounts of
these proteins. Taproots of other forage legume species (Lotus,
Melilotus, and Trifolium) did not contain proteins
that cross-reacted with antibodies raised against the three alfalfa
taproot proteins. The three proteins are glycosylated, and have
epitopes in common. The amino acids asparagine and aspartate make
up 15 mole percent of the three alfalfa taproot proteins. These
proteins possess features consistent with their role being vegetative
storage proteins.
Immunogold localization of nodule-enhanced phosphoenolpyruvate
carboxylase in alfalfa. Robinson, D. L.; Pathirana, S. M.;
Gantt, J. S.; Vance, C. P. Department of Biology, Bellarmine College,
Louisville, KY 40205-0167, USA. Plant, Cell and Environment vol.
19 (5): p.602-608. Publication Year: 1996.
Phosphoenolpyruvate carboxylase (PEPC) plays a vital role in providing
carbon for the synthesis of malate and aspartate in Medicago
sativa root nodules. To investigate the relationship between
the cellular location of PEPC and root nodule metabolism, enzyme
localization was evaluated by immunogold cytochemistry using M.
sativa nodule PEPC antibodies. Gold labelling patterns in
effective nodules indicated that PEPC is a cytosolic enzyme and
was distributed relatively equally in both the infected and uninfected
cells of the nodule symbiotic zone. Labelling was also detected
in the pericycle cells of the nodule vascular system and within
inner cortical cells. When Lotus corniculatus was transformed
with a chimeric gene consisting of the 5'-upstream region of the
PEPC gene fused to beta -glucuronidase (GUS), subsequent GUS staining
in the nodules was consistent with immunogold localization patterns.
It is suggested that because of the occurrence of PEPC in both
infected and uninfected cells of the symbiotic zone and the reduced
amounts observed in ineffective nodules, PEPC plays a direct role
in supporting N2 fixation. PEPC localization in uninfected, interstitial
cells of the symbiotic zone indicated that these cells may also
have a role in nodule carbon metabolism. Moreover, it is concluded
that the association of PEPC with the nodule vascular system implies
a role for the enzyme in the transport of assimilates to and from
the shoot.
Rhizomatous Lotus corniculatus L. I. Taxonomic and cytological
study. Beuselinck, P.R.; Li, B.; Steiner, J.J. USDA, ARS,
Plant Genetic Research Unit, Columbia, MO. Crop science. v. 36
(1), p. 179-185. Publication Year: 1996.
Wild, putative Lotus corniculatus L. accessions from Morocco
differ distinctly from domesticated L. corniculatus in
that they produce rhizomes. Rhizomes may be useful in increasing
stand persistence of domesticated L. corniculatus. The
objective of this study was to identify to species the wild Lotus
accessions from Morocco (G31272, C31273, G31276, G31298, and G31317)
that present rhizomatous growth. Comparative morphological and
cytological analyses and intercrossing with L. corniculatus
were used in this study. Six morphological characters that distinguish
L. corniculatus and L. uliginosus Schkuhr. (the
only species in the genus Lotus recognized as producing
rhizomes) were used to categorize taxonomically the Moroccan accessions.
The Moroccan accessions were morphologically similar to L.
corniculatus with the exception of the rhizome trait. The
accessions were tetraploid with 2n = 4X = 24 somatic chromosomes.
Karyotype analyses detected more similarities than differences
between the Moroccan accessions and Norcen. Progeny were produced
from intercrosses between L. corniculatus cvs. Norcen and
AU Dewey and the Moroccan accessions. Hybridity of progeny was
verified by morphological and random amplified polymorphic DNA
(RAPD) analyses. A sample of reciprocal F1 progeny were tetraploid,
fertile, and consistent in their production of rhizomes. A combination
of morphological, chromosome, and karyotype analyses confirmed
accessions G31272, G31273, G31276, G31298, and G31317 as L.
corniculatus. This is the first description of L. corniculatus
with rhizomes.
Frost-seeding legumes into established switchgrass: establishment,
density, persistence, and sward composition. Gettle, R.M.;
George, J.R.; Blanchet, K.M.; Buxton, D.R.; Moore, K.J. USDA-ARS,
Field Crops Res. Unit, Ames, IA. Agronomy Journal. v. 88 (1),
p. 98-103. Publication Year: 1996.
Legumes incorporated into established switchgrass (Panicum
virgatum L.) could provide symbiotic N, improve herbage quality,
and extend the grazing season. Almost no information exists for
legume renovation of switchgrass by frost-seeding. The objective
of this study was to identify cool-season legumes that can be
established into switchgrass by frostseeding, yet not provide
excessive competition to the associated grass. Six legumes [biennial
'Polara' white-flowered sweetclover (Melilotus alba Medik.),
biennial 'Madrid' yellow-flowered sweetclover (Melilotus officinalis
Lam.),'Norcen' birdsfoot trefoil (Lotus corniculatus L.),
'Redland II red clover (Trifolium pratense L.), 'Apollo
Supreme' alfalfa (Medicago sativa L.), and a 50:50 mixture
of Redland II red clover and Norcen birdsfoot trefoil] were inoculated
with rhizobia and frost-seeded into established 'Cave-in-Rock'
switchgrass in mid-March of 1991 and 1992. These mixtures were
compared with switchgrass fertilized at four N levels (0, 60,
120, and 240 kg ha-1). Successful legume establishment was observed,
with an average of 24 and 25% of viable seed producing seedlings
by June for 1991 and 1992 seedings, respectively. Mean legume
density was 160 and 170 plants m-2 by June of the seeding year
(YR 1) and 95 and 55 plants m-2 by June of the second year (YR
2) for 1991 and 1992 seedings, respectively. Legume renovation
of switchgrass stands did not affect grass stem density by July
YR 1. Mean forage stand composition (based on stem counts) was
87, 67, and 45% legume in June, July, and August YR 2, respectively,
for 1991 seedings, and 54, 29, and 23% legume during the same
time periods for 1992 seedings. Legumes did not seriously reduce
switchgrass stem density, although red clover, birdsfoot trefoil,
and their mixture were more competitive than others. Legumes can
be successfully introduced into established Cave-in-Rock switchgrass
by frost-seeding and they will persist for at least 2 yr with
favorable weather.
Selection of cold-tolerant plants for growth in soils contaminated
with organics. Rogers, H. B.; Beyrouty, C. A.; Nichols, T.
D.; Wolf, D. C.; Reynolds, C. M. University of Arkansas, Fayetteville,
AR, USA. Journal of Soil Contamination vol. 5 (2): p.171-186 Publication
Year: 1996.
A mixture of organic chemicals (MOC) containing equal molar amounts
of benzoic acid, hexadecane, 2,2-dimethyl 4,n-propyl-benzene,
phenanthrene, pyrene, and either cycloheptane or cis-decahydronaphthalene
(cis-decalin) was applied to soil at rates of 0 to 8000 mg/kg.
In a plant-screening experiment, growth responses of four legumes
(lucerne (Medicago sativa), Trifolium pratense, Trifolium
repens, and Lotus corniculatus) and five non-legume
species (alpine bluegrass (Poa alpina), Deschampsia beringensis,
Phalaris arundinacea, Elytrigia repens (Elymus repens)
and Artemisia tilesii) were determined at 10 and 25 deg
C. The MOC applied at 2000 mg/kg reduced the growth of several
species without resulting in significant seedling death. At 10
deg C, the growth of alpine bluegrass in the 1000 and 2000 mg/kg
treatments of soil increased by more than 185%. In a plant growth
response experiment, alpine bluegrass and lucerne were grown in
soil that had been contaminated at rates of 0 and 2000 mg/kg.
at 14 weeks, the shoot and root dry weights of lucerne were 97%
lower than in the contaminated soil, while the shoot dry weight,
root dry weight, and root length of alpine bluegrass were 135,
235, and 268% higher, respectively. Except for pyrene, <23%
of the compounds comprising the MOC remained in the soil after
4 weeks and <5% after 14 weeks. The disappearance of the MOC
was not significantly influenced by the presence of lucerne or
alpine bluegrass.
Perennial legumes for the high rainfall zone of eastern Australia.
1. Evaluation in single rows and selection of Caucasian clover
(Trifolium ambiguum M. Bieb.). Hill, M. J.; Mulcahy,
C.; Rapp, G. G. CSIRO Division of Animal Production, Pastoral
Research Laboratory, Armidale, NSW 2350, Australia. Australian
Journal of Experimental Agriculture vol. 36 (2): p.151-163 Publication
Year: 1996.
A range of perennial legume species, including Trifolium ambiguum,
T. medium, Astragalus cicer, Coronilla varia, Lotus corniculatus,
L. pedunculatus (L. uliginosus) and Lespedeza
cuneata, were evaluated in glasshouse and field trials in
1989-92 at Armidale, New South Wales. Hexaploid germplasm of T.
ambiguum was subjected to selection for increased seedling
vigour, early biomass production and profuse flowering in glasshouse
screening and spaced plant field nurseries. On an acid, solodic
soil, T. ambiguum and T. medium grew modestly, Lotus
spp. grew vigorously initially but died out within 3 years, A.
cicer and C. varia failed to persist beyond 1 year,
but isolated plants of L. cuneata thrived. On an acid,
free-draining, red-basalt soil, all accessions grew vigorously
until early 1991. During the succeeding drought, Lotus
died out, A. cicer thinned out on the acid soil, but T.
ambiguum, T. medium and C. varia remained persistent
and productive. A large nursery of A. cicer accessions
on the same soil limed to 5 t/ha before planting remained vigorous
to the present. Superior hexaploid material of T. ambiguum
selected from spaced plants originated chiefly from CPI43909 and
the ARS-2678 germplasm collection from Utah, USA.
The effect of plant growth regulators on growth, morphology
and condensed tannin accumulation in transformed root cultures
of Lotus corniculatus. Robbins, M. P.; Evans, T. E.;
Morris, P. Cell Manipulation Group, Institute of Grassland and
Environmental Research, Plas Gogerddan, Aberystwyth, Dyfed SY23
3EB, UK. Plant Cell, Tissue and Organ Culture vol. 44 (3): p.219-227
Publication Year: 1996.
The effects were studied of four different classes of plant growth
regulators on root morphology, patterns of growth and condensed
tannin accumulation in transgenic root cultures of Lotus corniculatus
(bird's-foot trefoil). Growth of transformed roots in 2,4-D resulted
in decreased tannin levels relative to controls at concentrations
of 10-6 M and above, while gibberellic acid (GA3) inhibited tannin
accumulation at concentrations of 10-7 M and above. Benzyladenine
(BA) had little effect at low concentrations (10-7 M and below)
but resulted in an increase in tannin levels at 10-6 M. Abscisic
acid had little effect on levels of condensed tannins at any of
the concentrations used. Experiments involving growth regulator
addition and medium transfer demonstrated that 2,4-D inhibition
of tannin accumulation could be reversed by GA3 and BA, while
GA3 down-regulation could only be reversed by the addition of
2,4-D. Although 2,4-D inhibited tannin accumulation, addition
of 2,4-D to root cultures grown for 14 or 28 days in the absence
of plant growth regulators stimulated both growth and tannin biosynthesis.
Characteristic alterations in root morphologies accompanied growth
regulator-mediated modulation of tannin biosynthesis. Growth in
2,4-D resulted in partially de-differentiated root cultures while
growth in GA3 produced roots with an elongated phenotype. Restoration
of tannin biosynthesis in 2,4-D-treated roots was accompanied
by root re-differentiation and the production of new lateral roots.
Strategy for catch crop development. I. Hypothetical ideotype
and screening of species. Karlsson-Strese, E. M.; Umaerus,
M.; Rydberg, I. Julita gard och museer, S-640 25 Julita, Sweden.
Acta Agriculturae Scandinavica. Section B, Soil and Plant Science
vol. 46 (2): p.106-111 Publication Year: 1996.
Hypothetical criteria were defined for a catch crop insown in spring cereals with the main purpose of reducing leaching of nitrogen. The criteria were applied in the screening of a large variable plant material from three groups: Poaceae, Fabaceae and species from other families. Variation in the characters of interest between and within species was recorded in spaced field plantings. Perennial species adapted to the Nordic climate possessed many of the characteristics expected to be desirable. Accessions, expected to have a potential as catch crops were identified in all three groups. The group "other families" is of great interest. The most interesting species for further experiments were Cichorium intybus, biennial species in Brassicaceae, Lotus corniculatus, Trifolium fragiferum and Lolium spp.
Yield response of legume seedlings to simulated insect cotyledon
damage and nutrient availability. Ferguson, C. M.; Shand,
J. A.; Evans, A. A. AgResearch, Invermay Agricultural Centre,
Private Bag 500034, Mosgiel, New Zealand. Proceedings of the Forty
Eighth New Zealand Plant Protection Conference, Angus Inn, Hastings,
New Zealand, August 8-10, 1995. Conference Title: Proceedings
of the Forty Eighth New Zealand Plant Protection Conference, Angus
Inn, Hastings, New Zealand, August 8-10, 1995. p.213-218 Publication
Year: 1995.
Seedlings of 9 legume species (Trifolium repens, T. ambiguum, T. hybridum, T. pratense, Lotus corniculatus, L. pedunculatus (L. uliginosus), Coronilla varia, Lupinus alpinus and lucerne) in pots were subjected to simulated insect defoliation by removing 0, 0.5, 1, 1.5 or 2 cotyledons. Foliage and root yields were measured after 8 weeks. The reaction of T. repens, T. ambiguum, and lucerne to the same levels of defoliation was further investigated with 3 balanced nutrient levels (high, medium or low) but without nitrogen. Foliage and root production and the amount of nitrogen fixed were measured 8 weeks after defoliation. Growth of all legume species decreased as simulated damage increased but some evidence suggested that the response varied between species. No association between simulated damage and nitrogen fixation was demonstrated but nutrient availability was shown to be of greater importance to plant growth than damage to cotyledons.
Influence of lime and calcium:magnesium ratio on alfalfa and
birdsfoot trefoil yields. Reid, W. S. Department of Crop and
Atmopsheric Sciences, 803 Bradfield Hall, College of Agriculture
and Life Sciences, Cornell University, Ithaca, NY 14853, USA.
Communications in Soil Science and Plant Analysis vol. 27 (5-8):
p.1885-1900 Publication Year: 1996.
In a field experiment in 1974, the effects of lime and Ca:Mg ratio
in the lime on Medicago sativa and Lotus corniculatus
DM yields and botanical composition of hay were examined. 0, 6.7,
13.4, 20.2 or 33.6 t lime/ha was applied to an acid (pH 4.7) Mardin
silt loam soil (coarse-loamy, mixed, mesic typic Fragiochrepts).
Using 4 commercial available lime sources and 2 mixtures of these
lime sources, 6 Ca:Mg ratios were established for each lime rate.
Calcium and/or magnesium sulfate were applied to plots that received
no lime to obtain Ca:Mg ratios similar to those on the limed plots.
The initial Morgan's solution extractable Ca was 450 mg/kg and
Mg was 25 mg/kg. A 5 x 5 Latin Square design with 5 lime rates
and 5 replications was used with the 6 Ca:Mg ratios as lime subplots.
To improve mixing, portions of each lime treatment were applied
before and after ploughing in 1974 and after ploughing in Apr.
of 1975. M. sativa and L. corniculatus were sown
to half of each plot. The plots were cut for hay 2 or 3 times
each year for 5 years. The M. sativa hay yield and legume
component were significantly increased by the first two lime rates
(6.7 and 13.4 t/ha); however, the L. corniculatus hay and
legume component were significantly increased only by the first
lime rate. Maximum yields for the legume component of both crops
occurred at a soil pH of 6.5. The Ca:Mg ratios resulting from
adding limes with different Ca and Mg contents had no significant
effects on the total DM yields, percent legume in hay or M.
sativa and L. corniculatus yields. It was concluded
that it is difficult to justify the use of Ca and Mg base saturation
ratios for lime recommendations, or for determining the Mg concentration
needed with lime. Soil samples taken in autumn of 1976 had mean
soil pH values of 4.6, 5.7, 6.1, 6.4 and 6.7 for the stated lime
rates, respectively.
Effects of nitrogen supply, variety and Rhizobium inoculation
on growth and nitrogen fixation of birdsfoot trefoil. Chun,
W. B.; Hoveland, C. S. College of Agriculture, Chonnam National
University, Kwangju 500-757, Korea Republic. Korean Journal of
Animal Science vol. 37 (2): p.193-202 Publication Year: 1995.
Shoot, root and nodule DW and N-fixing activity were higher in
Lotus corniculatus cv. AU Dewey than cv. Fergus. N fertilizer
application increased shoot and root DW but decreased N-fixing
activity and nodule DW. N-fixing activity increased up to 21 weeks
after sowing and decreased thereafter. Rhizobium inoculation
only had an effect without N fertilizer application. N contents
of shoots and roots were not affected by N fertilizer or Rhizobium
inoculation.
Methods of establishing Lotus corniculatus in native
pastures of the region of Campos Gerais, Parana. Original
Title: Metodos de implantacao do cornichao (Lotus corniculatus
L.) em pastagens nativas de Regiao dos Carupos Gerais do Parana.
Postiglioni, S. R. Instituto Agronomico do Parana, 84001-970 Ponta
Grossa, PR, Brazil. Boletim Tecnico - Instituto Agronomico do
Parana (No. 46): 17 pp. Publication Year: 1995.
In field trials in Ponta Grossa in 1988-91, L. tenuis cv.
Sao Gabriel was sown into natural grassland by broadcasting after
passage of a heavy or light harrow or sown with no previous cultivation.
The pasture was given 3 t/ha dolomitic limestone and 300 kg 10:30:10
NPK/ha before sowing the legume. Although average DM yield of
L. corniculatus was highest (1.51 t/ha/year) following direct
sowing, differences were not significant and total annual forage
DM yield ranged from 3.71 to 4.57 t/ha following light and heavy
harrowing, respectively. Sowing method had no significant effect
on forage CP content (10.4-11.4%) or in vitro DM digestibility
(50.2-51.9%).
Ballast plants and grain mill plants which appeared after soil
was dug out. Original Title: Ballastplanter og molleplanter
som spirte etter graving i jorden. 1994. Blyttia vol. 52 (4):
p.149-153.
Anagallis arvensis, Coronopus didymus, Euphorbia peplus and
Mercurialis annua are recorded from the seed bank of Norwegian
habitats. Coronopus didymus, Erucastrum gallicum, Salvia verticillata,
Sisymbrium loeselii, Lotus angustissimus, Silene noctiflora and
Hyoscyamus niger are recorded from the seed bank around Norwegian
grain mill areas.
Plant regeneration and genetic transformation of Lotus angustissimus.
Nenz, E.; Pupilli, F.; Paolocci, F.; Damiani, F.; Cenci, C. A.;
Arcioni, S. 1996. Plant Cell, Tissue and Organ Culture vol. 45
(2): p.145-152.
Culture conditions were established for callus induction and growth
from different explants of L. angustissimus. Calluses were
obtained from hypocotyls, leaves, stems, cotyledons and roots
cultured on media containing 2,4-D or alpha -NAA with kinetin,
N6- DELTA 2-isopentenyladenine or benzyladenine (BA) in different
combinations and concentrations. Only those calluses induced in
the presence of alpha -NAA with BA or kinetin produced shoots.
Calluses induced from hypocotyl explants were the most efficient
in regeneration of shoots. Transformation with an Agrobacterium
rhizogenes binary vector carrying the plasmid pBI 121.1 is
reported. The percentage of cotransformation was estimated by
testing GUS activity in hairy roots. The integration of Ri T-DNA
and the NPTII gene in transformed plants was confirmed by molecular
analyses and in vitro culture of transgenic tissues in the presence
of kanamycin.
Productivity of Lotus corniculatus L. (bird's-foot trefoil)
in the UK when grown under low-input conditions as spaced plants,
monoculture swards or mixed swards. Bullard, M. J.; Crawford,
T. J. Grass and Forage Science vol. 50 (4): p.439-446: 1995.
The productivity of L. corniculatus was assessed
under low-input conditions at 3 sites in the north of England.
An initial study in 1989 and 1990 compared 14 accessions of L.
corniculatus with Trifolium repens and T.
pratense grown as spaced plants at 2 sites with contrasting
soil conditions. One site represented good agricultural land,
the other poor-quality, marginal land. Yields of all species and
accessions were significantly lower on the marginal site. Seasonal
yields (averaged over sites) of L. corniculatus cultivars averaged
52 g DM/plant and 170 g in 1989 and 1990 respectively. General
trends over both seasons were that T. repens and T.
pratense yields were high but some L. corniculatus
cultivars (Empire, Franco, Leo) and naturalized UK 'aliens' were
similar to at least one of the Trifolium spp. in each year.
Yields from L. corniculatus ecotypes from the UK and Norway
were very low in comparison with the cultivars. A larger-scale
study of 18 L. corniculatus, 2 L. uliginosus, 3
T. repens and 2 T. pratense accessions was undertaken
on an upland, calcareous site in 1990. Legumes were assessed in
2 m x 2 m swards either grown alone or in a mixture with grass.
Establishment and productivity of L. uliginosus and
T. pratense accessions were poor, with seasonal yields no
greater that 50 g DM/m2. When grown alone, L. corniculatus
yields were higher than those of both Trifolium spp., and
averaged 1080 g/m2. In mixed swards, L. corniculatus constituted
a higher proportion of the total DM yield (26% and 62% at first
and second cuts, respectively) than the other legume species.
It is concluded from these studies that L. corniculatus
is suited to marginal or free-draining calcareous soils under
low-input conditions, and consequently has more potential for
use in the UK than has previously been reported.
Effects of nitrogen supply on growth and nitrogen fixation
of birdsfoot trefoil during primary growth. Chun, W. B.; Hoveland,
C. S. Proceedings of the 7th AAAP Animal Science Congress, Bali,
Indonesia, 11-16 July, 1994. Proceedings of the 7th AAAP Animal
Science Congress, Bali, Indonesia, 11-16 July, 1994.
In a greenhouse pot experiment, birdsfoot trefoil (Lotus
corniculatus) cv. AU Dewey and Fergus seeds were inoculated
with Rhizobium and seedlings were given half-strength Hoagland
solution with or without supplemental N. Root and shoot samples
were assessed at 15-24 weeks after sowing. Shoot DW was higher
in AU Dewey than Fergus at all assessments. Supplemental N increased
shoot DW and decreased N fixation.
Seasonal changes in nonstructural carbohydrates, protein, and
macronutrients in roots of alfalfa, red clover, sweetclover, and
birdsfoot trefoil. Li Rong; Volenec, J. J.; Joern, B. C.;
Cunningham, S. M. Crop Science vol. 36 (3): p.617-623. 1996.
Root total non-structural carbohydrate (TNC) has been studied,
but little is known about seasonal trends in proteins and other
macronutrients in legume roots. Studies were conducted to determine
how winter hardening and resumption of growth in spring influence
(i) concentrations of sugars and starch, and activities of amylases;
and (ii) protein concentration and composition, and abundance
of N, P, and K. Alfalfa (lucerne) (Medicago sativa), red
clover (Trifolium pratense), birdsfoot trefoil (Lotus
corniculatus), and biennial sweetclover (Melilotus officinalis)
were seeded in rows in the field in May and roots were sampled
at approximately monthly intervals in autumn and biweekly in spring.
All species accumulated high root TNC and starch concentrations
in autumn. Starch and TNC concentrations declined throughout winter,
but increased in roots of alfalfa and red clover in May. Starch
accumulation and degradation patterns in spring were correlated
with root endoamylase activity. Root sugar concentrations increased
three-fold from October to November. Root N and soluble protein
concentrations increased 50% between September and December, and
declined between March and May. Specific proteins accumulated
to high concentrations in alfalfa roots during autumn. Root P
increased 50% between October and April and was associated with
an increase in root phytate. Proteins, N, P and phytate accumulated
during winter hardening in autumn in roots of these forage legume
species that, in conjunction with TNC, may supply nutrients to
regrowing shoots in spring.
Establishing multi-cut swards. Yushchak, V. S. Kormoproizvodstvo
(No. 3): p.29-33: 1994.
Experiments on renovation of degraded grassland on a 15 deg NW-facing
slope at 560 m alt. in the Carpathians in 1985-92 are reported.
A mixture of Trifolium pratense, Lotus corniculatus, Festuca
pratensis, F. arundinacea, Arrhenatherum elatius, Lolium multiflorum
and Phleum pratense was successfully established under
a companion crop of peas + oats for green forage. In 1986-90,
an early maturing mixture of T. pratense, Dactylis glomerata,
A. elatius and L. multiflorum, an intermediate maturing
mixture of T. pratense, F. arundinacea, F. pratensis and
L. multiflorum and a late mixture of T. pratense, F. pratensis,
P. pratense and L. multiflorum were sown at 10, 15
or 20 million seeds/ha. Average hay yields of the 3 mixtures were
similar at a given sowing rate and increased from 7.30-7.80 t/ha
at the lowest sowing rate to 9.92-10.58 t at the highest. Denser
sowing tended to increase the proportion of legumes and decrease
that of forbs. The effects of delay in cutting on yield and chemical
composition of these mixtures in 1988-92 are reported. Combined
broadcast and row sowing gave the best results. Mixtures including
T. pratense and L. corniculatus were high yielding
but the legumes did not persist well. In 1986-89, applying 60
kg K2O/ha increased the hay yield of a grass-legume mixture from
4.05 to 5.17 t/ha and further addition of 45-120 kg P2O5/ha increased
yield to 6.22-9.04 t. In 1986-92, hay yield and percentage leaf
increased with increasing N rates in the range 120-180 kg/ha.
The effect of N varied considerably depending on weather conditions.
Unusual branching in the seedlings of Lotus japonicus-gibberellins
reveal the nitrogen-sensitive cell divisions within the pericycle
on roots. Kawaguchi, M.; Imaizumi-Anraku, H.; Fukai, S.; Syono,
K. Japan.Plant and Cell Physiology vol. 37 (4): p.461-470: 1996.
The effects of several plant growth regulators on the induction
of nodule-like structures on roots of Lotus japonicus were
investigated. Addition of gibberellin A3 (GA3) at concentrations
between 10-7and 10-4 M resulted in the formation of nodule-like
structures on roots when seedlings were plated on nitrogen-free
Fahraeus agar medium. GA4 also induced such outgrowths but was
less active than GA3. Application of an inhibitor of auxin transport,
N-(1-naphthyl)-phthalamic acid (NPA) and of kinetin, which have
been reported to induce pseudonodules in other legumes, had no
effect on L. japonicus. Microscopic observations showed that GA3-induced
nodule-like structures were caused by cell divisions within the
pericycle on the roots. In addition, the outgrowths elicited by
GA3 could be completely suppressed by the addition of 15 mM potassium
nitrate or ammonium nitrate. These results show that the pericycle
cells of the roots of L. japonicus are specifically sensitive
to gibberellins and that potential for cell division might be
modulated by nitrogen compounds. The effects of ancymidol and
uniconazole, two synthetic plant-growth retardants, were also
investigated. Both compounds at 3 x 10-5 M significantly increased
the number of stunted lateral roots. The unusual branching could
not be counteracted by the exogenous addition of GA3 but by 10-6
M brassinolide. The physiological role of brassinolide in the
initiation of lateral roots is discussed.
Allelopathic interactions between herbaceous species and trees
grown in topsoil and spoil media. Larson, M. M.; Patel, S.
H.; Vimmerstedt, J. P. Journal of Sustainable Forestry vol. 3
(1): p.39-52: 1995.
Dried foliage of several herbaceous species was mixed with either
vermiculite or 2 mine soils (topsoil and spoil) in 1-litre containers
planted with black locust (Robinia pseudoacacia), white
ash (Fraxinus americana) or sweetgum (Liquidambar styraciflua)
seedlings in a greenhouse. Germinated seed of northern red oak
(Quercus rubra) was planted in containers previously sown
with the herbaceous species. In vermiculite, black locust growth
was inhibited by additions of 12 g of litter of Medicago sativa,
Lotus corniculatus, Festuca arundinacea and Poa pratensis,
but stimulated by Trifolium pratense litter. White ash
growth was strongly inhibited by M. sativa and L. corniculatus
litter added to vermiculite at 12 and 18 g. In topsoil, sweetgum
was strongly inhibited by M. sativa litter. Both sweetgum
and red oak grew poorly in spoil, but sown Lolium perenne,
Dactylis glomerata and F. arundinacea grew well. Some
aspects of red oak growth were inhibited in containers sown with
M. sativa, L. perenne, D. glomerata, T. pratense or
F. arundinacea. Isolation and identification of allelopathic
compounds was not attempted, but these results suggest that there
may be important allelopathic interactions between herbaceous
species and trees planted on mined land.
Nodule development in legumes--the early stages involvement
of early nodulins, lectins, and other proteins. Hirsch, A.M.;
Fang, Y.; Brill, L.M.; Wycoff, K.L.; Niner, B.M.; Brandt, J.P.;
Van Rhijn, P. 1995. In: Nitrogen fixation fundamentals
and applications. Proceedings of the 10th International Congress
on Nitrogen Fixation, St. Petersburg, Russia, May 28-June 3, p.
299-304.
Nod metabolites and other compounds excreted by Rhizobium spp.
Martinez, E.; Laeremans, T.; Poupot, R.; Rogel, M.A.; Lopez,
L.; Garcia, F.; Vanderleyden, J.; Prome, J.C.; Lara, F. In:
Nitrogen fixation fundamentals and applications proceedings of
the 10th International Congress on Nitrogen Fixation, St. Petersburg,
Russia, May 28-June 3, 1995, p. 281-286.
Influence of lime and calcium magnesium ratio on alfalfa and
birdsfoot trefoil yields. Reid, W.S. Communications in soil
science and plant analysis. 1996. v. 27 (5/8), p. 1885-1900.
A study was established in 1974 to examine the effects of lime
and calcium-magnesium (CaMg) ratio in the limes on alfalfa (Medicago
sativa) and birdsfoot trefoil (Lotus corniculatus L.)
hay yields and botanical composition of the hay. Lime was applied
at rates of 0, 6.7, 13.4, 20.2, and 33.6 Mg/ha to an acid (pH
4.7) Mardin silt loam soil (coarse-loamy, mixed, mesic typic Fragiochrepts).
Using four commercially available lime sources and two mixtures
of these lime sources, six CaMg ratios were established for each
lime rate. Calcium and/or magnesium sulfate were applied to plots
that received no lime to obtain CaMg ratios similar to those on
the limed plots. The initial Morgan's solution extractable Ca
was 450 mg/kg and Mg was 25 mg/kg. A 5 X 5 Latin Square design
with five lime rates and five replications was used with the six
CaMg ratios as lime subplots. To improve mixing, portions of each
lime treatment were applied before and after plowing in 1974 and
after plowing in April of 1975. Alfalfa and birdsfoot trefoil
were planted to one-half of each plot. The hay was harvested two
or three times each year for five years. The alfalfa hay yield
and legume component were significantly increased by the first
two increments of lime (6.7 and 13.4 Mg/ha); however, the birdsfoot
trefoil hay and legume component were significantly increased
only by the first increment of lime. Maximum yields for the legume
component of both crops occurred at a soil pH of 6.5. The CaMg
ratios resulting from adding limes with different Ca and Mg contents
had no significant effects on the total dry matter hay yields,
percent legume in hay or alfalfa and birdsfoot trefoil yields.
It is difficult to justify the use of Ca and Mg base saturation
ratios for lime recommendations, or for determining the Mg concentration
needed within the lime. Soil samples taken in fall of 1976 had
mean soil pH values of 4.6, 5.7, 6.1, 6.4, and 6.7 for the five
lime rates.
Rep-PCR mediated genomic fingerprinting of rhizobia and computer-assisted
phylogenetic pattern analysis. Schneider, M.; Bruijn, F. J.
de. World Journal of Microbiology & Biotechnology vol. 12
(2) p.163-174. 1996.
A rapid and reproducible method for genomic fingerprinting of
rhizobia and other soil microbes that interact with plants is
described. The method utilises oligonucleotide primers that correspond
to conserved motifs in naturally occurring interspersed repetitive
DNA elements in bacteria (rep-elements), and the polymerase chain
reaction (rep-PCR). The rep-PCR amplifies inter-element genomic
DNA fragments of characteristic lengths thereby generating a genomic
fingerprint which resembles UPC bar code patterns, and as such
enable bacteria to be identified at the sub-species and strain
level, as well as for phylogenetic analyses. Therefore a highly
characteristic and reproducible rep-PCR generated genomic fingerprints
can be obtained not only from purified genomic DNA, but also directly
from rhizobial cells obtained from liquid culture, plate colonies,
and root nodule tissue. The effect of cell growth phase, serial
subculturing and other parameters on the reproducibility of the
rep-PCR fingerprinting protocol were assessed. Moreover, the results
of mixing experiments designed to determine if individual genomic
fingerprints can be recognized in mixtures of strains was attempted.
A review is also provided on the use of computer-based fragment
detection and phylogenetic analysis packages to analyse rep-PCR
generated genomic fingerprints of a collection of Rhizobium
loti and Bradyrhizobium strains nodulating different
Lotus spp.
Differential expression of the Sesbania rostrata leghemoglobin
glb3 gene promoter in transgenic legume and non-legume plants.
Szczyglowski, K.; Potter, T.; Stoltzfus, J.; Fujimoto, S. Y.;
Bruijn, F. J. de. Plant Molecular Biology vol. 31 (4) p.931-935.
1996.
The involvement of the Sesbania rostrata glb3 gene promoter
NICE (nodule-infected cell expression) element in root-enhanced
expression of the 5'-Srglb3-uidA-3'nos chimaeric gene was investigated
in transgenic Nicotiana tabacum plants. The full-length
wild-type Srglb3 promoter directed root meristem-enhanced expression
in transgenic tobacco plants. The expression pattern of nine selected
Srglb3 promoter mutations in the NICE element was examined in
transgenic tobacco plants and compared with the pattern observed
in nodules of transgenic Lotus corniculatus plants. The
results suggest that the highly conserved motifs in the NICE element
play an important role in expression in roots of non-legume plants.
Cytology of 2n pollen formation and pollen morphology in diploid
Lotus tenuis (Fabaceae). Rim YongWoo; Beuselinck, P.
R. American Journal of Botany vol. 83 (8) p.1057-1062. 1996.
Two genotypes of Lotus tenuis PI204882, a diploid (2n =
2x = 12), were identified as producing 2n pollen (maximum = 6%).
Research was undertaken to determine the mechanism(s) of 2n pollen
formation in the L. tenuis genotypes, and to morphologically
describe n and 2n pollen using light and scanning electron microscopy.
Meiotic studies revealed that 2n pollen resulted from tripolar
spindles during anaphase II of microsporogenesis. The 2n pollen
germinated well, although abnormal pollen tubes were observed.
The genetic constitution of 2n pollen resulting from tripolar
spindles is equivalent to first division restitution of meiosis.
Fresh and air-dried pollen samples exhibited differences in size
and shape under light and scanning electron microscopy. The size
of diploid (2n) pollen was larger than that of haploid (1n) pollen.
Normal haploid (1n) pollen was globose-prolate in shape, while
diploid (2n) pollen was tetrahedral.
Evaluation of Astragalus L. and Lotus L. on two
acid soil sites on the southern tablelands of New South Wales.
Kelman, W. M. Australian Plant Introduction Review vol. 26
p.17-38. 1996.
A more diverse range of perennial pasture legumes can be used
to fill niches not well exploited by commonly used species in
southern Australia. Some 162 accessions of Astragalus and
118 accessions of Lotus were evaluated for seasonal productivity
and persistence on a limed (pH 5.2 in CaCl2) and an unlimed (pH
4.3 in CaCl2) site on Ginninderra Experiment Station, ACT. A further
59 accessions of L. corniculatus were evaluated on an acid site
(pH 4.07 in CaCl2) at Boundary Creek, NSW. The Astragalus
species were persistent but unproductive on the unlimed site.
On the limed site some accessions of A. cicer and A.
glycyphyllos were as productive as white clover (Trifolium
repens) and strawberry clover (T. fragiferum) cultivars
in the summer. However, lack of cold season growth activity limits
the direct use of these accessions in these environments. L.
pedunculatus (L. uliginosus) was more tolerant of the
unlimed soil site than the other Lotus species and white
clover but autumn and spring growth scores were lower than those
of the clover species. Improved seed production and lowered condensed
tannin levels were identified as breeding objectives in L.
pedunculatus. Two L. tenuis accessions had better autumn
growth scores than the other Lotus species and a role in
saline soils is suggested for this species. The annual L. suaveolens
accessions produced vigorous seedling populations on both
sites and it is speculated that interspecific hybridization with
the perennial species might confer better autumn seedling establishment
on the progeny. At Boundary Creek some prostrate forms of L.
corniculatus from Spain had high herbage yields but unusually
high condensed tannin concentrations. The prostrate forms need
further evaluation under grazing by sheep.
Biochemical study of accessions of birdsfoot trefoil (Lotus
corniculatus L.) from the breeding point of view. Kyuchukova,
A. Rasteniev"dni Nauki vol. 32 (6) p.135-137. 1995.
Analysis of fodder from the first and second cuts of 15 local
and introduced varieties in 1991 showed that crude protein content
ranged from 19.43% to 21.53% in the first cut and from 18.89%
to 22.15% in the second. The concentration of condensed tannins
was 1.32-1.64%. This did not have an adverse effect on dry matter
digestibility. Some varieties appeared promising for use in breeding
for fodder quality.
Study of Osmia coerulescens L. (Hymenoptera, Megachilidae)
- a pollinator for lucerne. II. Pollinating and building activity.
Dochkova, B. Rasteniev"dni Nauki vol. 32 (6) p.64-66. 1995.
Studies during 1988-91 in the Pleven area of Bulgaria indicated
that only the females of this solitary bee species engage in nest
building and pollinating activity. They opened and pollinated
87.5% of visited Medicago sativa flowers and 98.4 to 100%
of visited flowers of Lotus corniculatus and Onobrychis
sativa (O. viciifolia). Osmia coerulescens (O.
caerulescens) settled readily into artificial nests made of
wild cane or of wood and appeared suitable for limited open pollination
of lucerne breeding material.
Application of high molecular weight DNA cloning in legume
nodulation gene analysis. Gresshoff, P. M.; Funke, R.; Caetano-Anolles,
G.; Prabhu, R.; Pillai, S. ; Kolchinsky, A.; Landau-Ellis, D.
Induced mutations and molecular techniques for crop improvement.
Proceedings: Induced mutations and molecular techniques for crop
improvement. Proceedings, Vienna, Austria, 19-23 June 1995.p.275-285.
1995.
High molecular weight (HMW) DNA was isolated from Glycine max
and the model legume Lotus japonicus for legume genome
analysis. The primary objectives were the gene regions that control
nodulation, early plant-microbe interaction and cell division
responses. HMW DNA was separated by pulse field gel electrophoresis
and analysed with closely linked RFLP markers co-hybridized with
clones, permitting estimation of the physical distances related
to recombination frequency. In the distal region of molecular
linkage group H containing one of the genes controlling nodule
number autoregulation and symbiotic nitrate tolerance (i.e. the
nts gene), 1 cM was equivalent to less than 500 kb. Partially
digested EcoRI soyabean and L. japonicus HMW DNAs were
cloned into pYAC4. Stable yeast artificial chromosomes (YACs)
carrying up to 960 kb DNA were generated. The average insert size
was 200 kb. Hybridization with total genomic soyabean DNA revealed
YACs with different amounts of repeated DNA sequences. Mapping
of the end clones demonstrated whether the YACs were chimaeric.
YACs of different complexity were used for chromosome identification
using degenerate primer PCR and fluorescent in situ hybridization.
This approach is a fast alternative to testing for YAC chimaerism.
Single arbitrary and structured mini-hairpin primers were used
to amplify and DNA fingerprint the YACs, providing a means of
identifying the additional markers needed for contig construction.
HMW DNA was cloned into the F plasmid bacterial artificial chromosome
(BAC) vector. The YACs and BACs were also constructed with DNA
from L. japonicus.
Soil loss control and soil properties improvement based on
cropping systems with cover plants and hedgerows in Reunion Island.
Perret, S.; Michellon, R.; Tassin, J. Proceedings of the third
congress of the European Society for Agronomy, Padova University,
Abano-Padova, Italy, 18-22 September 1994. p.736-737. 1994.
Water runoff and erosion were studied on severely and moderately
degraded bare andisol soils under 25 years of Pelargonium
monoculture, a 6-year rotation including Pelargonium and
food crops, and Pelargonium with cover crops of Pennisetum
clandestinum or Lotus uliginosus. The use of a cover
crop significantly decreased soil erosion. Soil permeability increased
under cover crops, especially where Calliandra calothyrsus
was used as a hedgerow on plot boundaries. Soil fauna, organic
matter turnover and mineralization all increased below the cover
crops. Crop rotations alone could not restore soil properties.
Herbage production from swards containing a range of grass,
forb and clover species and under extensive management. Fisher,
G. E. J.; Baker, L. J.; Tiley, G. E. D. Grass and Forage Science
vol. 51 (1) p.58-72. 1996.
Three small plot experiments were conducted to investigate the
effects of species of grass and forbs, defoliation regime, inclusion
of white clover (Trifolium repens) and forb blend on the
herbage DM yield, botanical composition and mineral content of
swards managed with zero fertilizer inputs. The results of all
three experiments were characterized by decline in herbage production
and large variations in treatment effects over the harvest period.
When sown singly with a standard grass mix the species that competed
well with grasses and produced annual forb herbage yields greater
than 2.0 t DM ha-1 were black knapweed (Centaurea nigra),
oxeye daisy (Leucanthemum vulgare), ribwort plantain (Plantago
lanceolata), burnet (Sanguisorba officinalis), birdsfoot
trefoil (Lotus corniculatus), chicory (Cichorium intybus),
kidney vetch (Anthyllis vulneraria), red clover (T.
pratense) and white clover. When sown singly with a standard
forb mix, grass species significantly affected the annual yield
of total, grass and forb herbage. The species that most suppressed
the yield of forbs were common bent (Agrostis tenuis (A.
capillaris)), Yorkshire fog (Holcus lanatus) and perennial
ryegrass (Lolium perenne). Those that allowed for the highest
yield of forbs were rough meadow grass (Poa trivialis),
sweet vernal grass (Anthoxanthum odoratum) and crested
dogstail (Cynosurus cristatus). Averaged over the three
harvest years, defoliation regime did not significantly affect
herbage production, but the inclusion of white clover in mixtures
increased the yield of grasses. The use of rosette-type forb blends
increased forb yield, compared with erect-type blends. The effects
of treatments on herbage N and mineral contents and yields were
inconsistent. However, there was some evidence to support the
view that the presence of forb species in swards can result in
greater contents of minerals in herbage, compared with grass-only
swards.
Contributions to the improvement of degraded permanent pasture
lands from the Moldavian forest steppe, by fertilizer applications,
oversowing and radical repairs. Original Title Contributii
la imbunatatirea pajistilor permanente degradate din silvostepa
Moldovei prin fertilizare, suprainsamantare si refacere radicala.Iacob,
T.; Dumitrescu, N.; Vintu, V.; Samuil, C. Cercetari Agronomice
in Moldova vol. 28 (3/4) p.127-132. 1995.
In 1988-93, 0-100 kg N + 0-75 kg P2O5 + 0-100 kg K2O + 0-40 t
FYM/ha was applied to a degraded Festuca valesiaca pasture.
DM yields ranged from 2.9 t/ha with no fertilizers to 5.2 t with
100 kg N + 50 kg P2O5 + 50 kg K2O. In 1986-90 on a permanent F.
valesiaca pasture with 10-42 deg slope, 0-150 kg N/ha was
applied. DM yields increased with decrease in slope and increase
in N rate and ranged from 2.1 t/ha in the unfertilized control
on a 40-42 deg slope to 6.1 t with 150 kg N on a 10-15 deg slope.
In 1988-93 a pasture was prepared using a rotary sower, chisel
plough or disc harrow and sown with Bromus inermis + Onobrychis
viciifolia alone or with Dactylis glomerata and
Lotus corniculatus and 20 t FYM alone or with 50 kg N + 25
kg P2O5, or 40 t FYM alone or with 100 kg N + 50 kg P2O5/ha were
applied. DM yield increases of 72-190% were due to fertilizer
applications, 65-131% were due to oversowing + fertilizers and
116-226% were due to resowing + fertilizers and ranged from 1.9
t/ha in the untreated control to 6.2 t with the 2 species mixture
+ discing + the higher NP rate.
Frost-seeding legumes into established switchgrass forage yield
and botanical composition of the stratified canopy. Gettle,
R. M.; George, J. R.; Blanchet, K. M.; Buxton, D. R.; Moore, K.
J. Agronomy Journal vol. 88 (4) p.555-560. 1996.
A field study was conducted on a Webster-Nicollet soil (fine-loamy,
mixed, mesic, Typic Haplaquoll-Aquic Hapludoll) at Ames, Iowa,
to compare herbage DM yield and botanical composition of legume-renovated
switchgrass (Panicum virgatum) with that of N-fertilized
switchgrass. Five inoculated forage legumes (Melilotus alba,
M. officinalis, Lotus corniculatus, Medicago sativa or
Trifolium pratense) and a legume mixture (T. pratense and
L. corniculatus) were frost-seeded into an excellent stand
of established switchgrass cv. Cave-in-Rock in mid-March of 1991
and 1992. Grass-legume DM yield was compared with N application
(0, 60, 120 or 240 kg ha-1) in the sowing year (YR 1) and the
second year (YR 2). Harvested samples were separated into grass
and legume components, and further divided into upper and basal
canopy. Nitrogen application provided the greatest upper and basal
canopy yields in both June and July of YR 1. By June YR 2, legume
renovation increased upper-canopy yields more than 240 kg N. Upper-canopy
YR 2 yields of grass-legume mixtures sown in 1991 remained greater
than for 240 kg N in July, and were similar to 120 kg N in August.
During a wetter and cooler than normal summer, YR 2 yields of
upper-canopy grass-legume mixtures sown in 1992 were similar to
60 and 120 kg N by July, and similar to both unfertilized and
N-fertilized switchgrass by August. It is concluded that yields
of legume-renovated switchgrass were generally greater than for
mid to high levels of N application during YR 2. Because of relatively
low herbage production during YR 1, it is suggested that producers
should consider frost-seeding legumes into only part of existing
switchgrass pastures, while applying N to the remaining non-renovated
pasture to maintain high forage supply and pasture productivity.
Characterization of rhizobia nodulating Lotus subbiflorus
from Uruguayan soils. Irisarri, P.; Milnitsky, F.; Monza,
J.; Bedmar, E. J. Plant and Soil vol. 180 (1) p.39-47 1996.
The generation times, acid production, carbon utilization, immunological
properties, plasmid content, protein profile and symbiotic properties
of 15 isolates of rhizobia nodulating Lotus subbiflorus
(isolated from 8 representative soils in Uruguay) were studied.
Rhizobium loti strain NZP2037 and Bradyrhizobium
sp. (Lotus) strain NZP2309 were used as reference strains
for fast- and slow-growing rhizobia, respectively. Isolates Ls11,
Ls22, Ls31, Ls42, Ls71, Ls81, Ls82 and Ls552 were obtained from
the Florida region, while Ls3, Ls4, Ls5, Ls7, LsS3, Ls1B3 and
Ls1B4 were from Durazno. The seeds of L. subbiflorus cv.
Rincon, L. pedunculatus (L. uliginosus), L. tenuis
and L. corniculatus were surface sterilised, inoculated
with rhizobium isolates and pot-grown under greenhouse conditions.
Based on specific growth rates, carbon source utilization and
acid production, 13 out of the 15 isolates could be assigned to
the slow-growing group of rhizobia (bradyrhizobia). Using antisera
against the whole cells of 3 isolates, the 15 isolates were separated
into 3 groups. Only the slow-growing isolate Ls4 and the fast-growing
Ls5 and Ls552 lacked cross-reactivity with any of the sera tested.
Electrophoretic mobilities of whole cell protein from 7 out of
the 8 isolates included in the serogroup represented by strain
Ls31 were identical. Similarly, isolates Ls1B3 and Ls 1B4 (both
in serogroup Ls1B3), exhibited the same pattern of cell proteins.
In contrast, isolates Ls3 and Ls7 (belonging to serogroup Ls7),
differed in protein profile. Plant growth experiments revealed
that all of the isolates effectively nodulated L. subbiflorus
and L. pedunculatus, but were unable to form effective
nodules on L. tenuis and L. corniculatus. All isolates
exhibited similar effectiveness in symbiosis with L. subbiflorus,
except isolate Ls7, which resulted in significantly higher plant
dry weight.
Seasonal changes in nonstructural carbohydrates, protein, and
macronutrients in roots of alfalfa, red clover, sweetclover, and
birdsfoot trefoil. Li, R.; Volenec, J.J.; Joern, B.C.; Cunningham,
S.M. Crop Science. v. 36 (3), p. 617-623. 1996.
Root total nonstructural carbohydrate (TNC) has been studied,
but little is known about seasonal trends in proteins and other
macronutrients in legume roots. Our objectives were to determine
how winter hardening and resumption of growth in spring influence
(i)concentrations of sugars and starch, and activities of amylases;
and (ii)protein concentration and composition, and abundance of
N, P, and K. Alfalfa (Medicago sativa L.), red clover (Trifolium
pratense L.),birdsfoot trefoil (Lotus corniculatus L.),
and biennial sweetclover (Melilotus officinalis L.) were
seeded in rows in the field in May and roots were sampled at approximately
monthly intervals in autumn and biweekly in spring. All species
accumulated high root TNC and starch concentrations in autumn.
Starch and TNC concentrations declined throughout winter, but
increased in roots of alfalfa and red clover in May. Starch accumulation
and degradation patterns in spring were correlated with root endoamylase
activity. Root sugar concentrations increased threefold from October
to November. Root N and soluble protein concentrations increased
50% between September and December, and declined between March
and May. Specific proteins accumulated to high concentrations
in alfalfa roots during autumn. Root P increased 50%between October
and April and was associated with an increase in root phytate.
Proteins, N, P, and phytate accumulated during winter hardening
in autumn in roots of these forage legume species that, in conjunction
with TNC, may supply nutrients to regrowing shoots in spring.
Effect of condensed tannins in Lotus corniculatus upon
lactation performance in ewes. Wang, Y.,Douglas, G.B.; Waghorn,
G.C.; Barry, T.N.; Foote, A.G. Journal of agricultural science.
v. 126 (pt.3), p.353-362. 1996.
Recent data on bird's foot trefoil growth with different seed
dosages, herbicide treatments and cutting phenophase. Nagy,
L. Irrigated Farming. p.169-170. 1995
Following on from earlier experiments to investigate forage, seed
yield and weeding facilities, this short paper outlines tests
carried out on yields, number of plants per meter, weeding and
also the germination capacity of bird's foot trefoil (Lotus
corniculatus). These have shown that higher seeding rates
resulted in higher seed yields, higher plant density, lower weed
numbers and similar germination compared to lower seeding rates.
Crop growth was affected by different herbicide treatments, e.g.
the effect of imazethapyr on seed yield and weeds was beneficial,
but tests also showed that cutting just before flowering had much
better effect on seed yield and germination than cutting after
flowering.
Experiences of usage of imidazoline derivatives in bird's foot
trefoil (Lotus corniculatus ssp. tenuifolius) stands.
Nagy, L. Irrigation Res. Inst., Szarvas, Hungary. Irrigated
Farming. p.163-168. 1995.
Post-em. Pivot 100 LC (with imazethapyr as the a.i.) was used
at 0.8 litres/ha after establishment of bird's foot trefoil. This
treatment achieved an approximate 30% decrease of gross weed weight
by harvesting time. Monocotyledonous weeds decreased more significantly
than dicotyledonous ones. Amounts of Chenopodium album, Sonchus
oleraceus, Hibiscus trionum and Cirsium arvense increased
slightly in plots treated with Pivot 100 LC. The fodder yield
of bird's foot trefoil was increased by 75-135% as a result of
the treatment. Pivot 100 LC and Scepter 150 LC (imazaquin (ammonium
salt)) were more selective when applied at the end of winter than
at 5-7 cm plant height. It was concluded that the selectivity
of the two herbicides with respect to pioneer bird's foot trefoil
is favourable.
Improving the acid-soil tolerance of Medicago sativa
by asymmetric somatic hybridisation. Stoutjesdijk, P.A.; Larkin,
P.J.; Sale, P.W.G. Plant-soil interactions at low pH: principles
and management. Proceedings of the Third International Symposium,
Brisbane, Queensland, Australia, 12-16 September 1993. p.455-457.
1995 Developments in Plant and Soil Sciences Vol. 64 Editors:
Date, R.A.; Grundon, N.J.; Rayment, G.E.; Probert, M.E. Kluwer
Academic Publishers, Dordrecht, Netherlands.
A protoplast electrofusion method for producing asymmetric somatic
hybrid plants which are essentially Medicago sativa with
small additions of donor Lotus pedunculatus (L. uliginosus)
chromatin is described. Differential aluminium tolerance by M.
sativa and L. pedunculatus was observed in vitro in
an aluminium containing medium. Hybrid colonies were screened
in the same medium for differences in growth rate. Approximately
900 of 4600 somatic hybrid colonies placed on this medium showed
growth rates and morphology indicative of transfer of aluminium
tolerance from Lotus to M. sativa. Regenerated plants
from the selected colonies are being tested for elevated tolerance
of aluminium.
Chemical content of Al-tolerant and Al-susceptible breeding
lines of white clover. Caradus, J.R.; Mackay, A.D. Plant-soil
interactions at low pH: principles and management. Proceedings
of the Third International Symposium, Brisbane, Queensland, Australia,
12-16 September 1993. p.439-445. 1995. Developments in Plant and
Soil Sciences Vol. 64. (Eds.) Date, R.A.; Grundon, N.J.; Rayment,
G.E.; Probert, M.E. Kluwer Academic Publishers Dordrecht, Netherlands.
Experimental breeding lines were developed from crosses between
genotypes selected within white clover (Trifolium repens)
cv. Grasslands Huia for either tolerance or susceptibility to
aluminium (Al). Using a diallel design, 3 tolerant (T) and 3 susceptible
(S) genotypes were crossed and reciprocals bulked. The chemical
content of these breeding lines was compared with that of Lotus
pedunculatus (L. uliginosus) cv. Maku grown in soil
with or without 400 micro g Al/g soil. The Al-tolerant white clover
genotypes had lower concentrations of Al and Fe in their shoots
but higher concentrations of Cu, K and P than those of Al-susceptible
plants. There was a significant trend of increasing percentage
change in shoot concentration of Al, Ca, Fe, S and Sr, and decreasing
change of Cu, K and P from T x T through T x S to S x S progenies
due to added Al. Added Al decreased monovalent cation (K) uptake
relative to divalent cation (Ca and Mg) uptake, but this effect
was much less for Al-tolerant selections than Al-susceptible selections.
It is proposed that the exclusion of Al from roots is a plausible
reason for the continued K uptake by Al-tolerant compared with
Al-susceptible white clover.
The effect of aluminium on the growth of a range of temperate
legume species and cultivars: a summary of results. Wheeler,
D.M.; Dodd, M.B. Plant-soil interactions at low pH: principles
and management. Proceedings of the Third International Symposium,
Brisbane, Queensland, Australia, 12-16 September 1993. p.439-445.
1995. Developments in Plant and Soil Sciences Vol. 64. (Eds.)
Date, R.A.; Grundon, N.J.; Rayment, G.E.; Probert, M.E. Kluwer
Academic Publishers Dordrecht, Netherlands.
The aluminium (Al) tolerance of 35 temperate legumes (136 accessions)
was determined in 74 experiments over a 2-year period in a low
ionic strength (2730 micro M) solution culture. For each accession,
the relationship between solution Al3+ activity ( micro M) and
relative root yields was determined using polynomial exponential
splines, and the Al3+ activity associated with a 50% reduction
in root yield (AlRY50) was calculated. All species tested in the
genera Adesmia, Medicago and Melilotus tended to
be very sensitive to aluminium (AlRY50 <1). Dorycnium pentaphyllum
was sensitive, whereas the AlRY50 of the D. hirsutum lines ranged
from 1.4 to 2.4 (mean 1.9). In Lotus and Trifolium,
the order of tolerance for each species (based on the AlRY50 mean
over lines) was L. tenuis, T. resupinatum (AlRY50 <0.5)
< T. balansae, T. fragiferum, T. hybridum and T.
pratense (AlRY50 0.5-1) < L. angustissimus, L. corniculatus,
L. subbiflorus, T. ambiguum, T. dubium, T. glomeratum (AlRY50
1-1.5) < T. amabile, T. repens, T. semipilosum, T. striatum,
T. tumens (AlRY50 1.5-2) < T. medium, T. polymorphum
(AlRY50 2-3) < T. subterraneum (AlRY50 3-4) <
L. pedunculatus (L. uliginosus) (AlRY50 >4).
Significant differences in Al tolerance between the lines were
noted for (with the range in AlRY50 in parenthesis) T. amabile
(0.1-2.6), T. ambiguum (0.8-1.6), T. medium (1.5-4.1),
T. repens (0.6-3.1), T. polymorphum (1.5-2.6), T.
semipilosum (1.2-2.0) and T. subterraneum (1.8-5.9).
Genetic transformation of Lotus corniculatus with
Agrobacterium tumefaciens and the analysis of the inheritance
of transgenes in the T1 generation. Webb, K.J.; Gibbs, M.J.;
Mizen, S.; Skot, L.; Gatehouse, J.A. Transgenic Research vol.
5 (5): p.303-312. 1996.
The herbage legume, Lotus corniculatus (bird's-foot trefoil),
was transformed using the disarmed Agrobacterium tumefaciens
strain LBA4404 (pAL4404) carrying a binary construct, pJit73.
This plasmid carries two antibiotic resistance genes, aphIV and
nptII encoding resistance to hygromycin and kanamycin respectively,
and the easily detectable reporter gene, uidA encoding the enzyme
beta -glucuronidase (GUS). Transgenic plants were regenerated
from two separate co-cultivations of leaves with A. tumefaciens
either with or without an acetosyringone pretreatment. A total
of 110 putative transformants were regenerated, 52 (47%) of which
grew on selection media containing hygromycin. Twenty-five plants
were analysed further for morphological variation and presence
of transgenes and were used to study the inheritance of expression
of the transgenes in the T1 generation. Expression patterns of
the transgenes in the T1 progeny generated from these 25 plants
differed. In the majority of plant lines aphIV and uidA transgenes
segregated together, but the apparent number of copies of the
transgenes varied. No expression of either transgene was detected
in the progeny from three plants, while the progeny from six other
plants were resistant to hygromycin but had no GUS expression.
Progeny of all of the remaining 16 plants had GUS activity. For
three plants, inheritance data were consistent with more than
one dose of uidA and aphIV; another two plants yielded data expected
for exactly one dose of both transgenes. In the progeny of the
remaining 11 plants, the percentage of seedlings expressing both
uidA and aphIV was lower than expected.
Elicitor mediated phytoalexin biosynthesis in transgenic root
cultures of Lotus corniculatus. Morris, P.; Thomas,
B.; Robbins, M.P. International symposium on natural phenols in
plant resistance, Volume I, 13-17 Sep., 1993, Weihenstephan, Germany.
Acta Horticulturae (No. 381): p.210-213.: 1994.
Agrobacterium rhizogenes-transformed root cultures of L.
corniculatus responded to both biotic and abiotic elicitors
resulting in the de novo synthesis of the typical Lotus
isoflavan phytoalexins vestitol and sativan, which accumulated
in both tissue and culture medium. Down regulation of constitutive
tannin biosynthesis by auxin resulted in accumulation of chalcones
and superinduction of phytoalexins on elicitation, whereas down
regulation of tannins with an antisense DFR gene did not result
in chalcone accumulation or in modified phytoalexin accumulation.
The elicitation of Lotus root cultures with GSH also caused
changes in root tip morphology due to differential injury to root
meristem cells.
An 'antisense' strategy for the genetic manipulation of condensed
tannin and isoflavonoid phytoalexin accumulation in transgenic
Lotus corniculatus L. Colliver, S. P.; Robbins, M.
P.; Morris, P. International symposium on natural phenols in plant
resistance, Volume I, 13-17 Sep., 1993, Weihenstephan, Germany.
Acta Horticulturae (No. 381): p.148-151. 1994.
An antisense chalcone synthase gene construct made using the cDNA
for chalcone synthase from Phaseolus vulgaris was introduced
into the genome of 3 clonal genotypes of L. corniculatus
via Agrobacterium rhizogenes. After initial screening,
30 antisense (AS) and 15 control (C) transformation events were
analysed and regenerative ability was found to be reduced in AS
root cultures. AS compared with C root cultures appeared to have
a higher growth rate which was related to the ability to accumulate
tannin.
Effect of nitrogen fertilizer application on birdsfoot trefoil
grown in the foothill region of central North Bulgaria. Aleksandrova,
B. Rasteniev"dni Nauki vol. 32 (5): p.193-195. 1995.
In a field trial on light grey pseudopodzolic soil at 385 m alt.
in 1989-92, Lotus corniculatus was given no fertilizer or 80,
160 or 240 kg N/ha alone or with 80 kg P2O5 + 80 kg K2O, or these
P and K rates without N. Average annual DM yields were 7.78 t/ha
with no fertilizer, 8.65 t with PK alone, 8.77-9.53 t with increasing
rates of N without PK and 9.04-10.35 t with PK and increasing
N rates. The percentage of L. corniculatus in the sward
varied considerably between cuts and years; by 1992 it was only
about 25% at the highest N rate, compared with about 65% with
no fertilizer, and remained over 40% with PK + 80 kg N.
Yield and forage quality of birdsfoot trefoil grown alone and
in mixtures with cocksfoot. Aleksandrova, B. Rasteniev"dni
Nauki vol. 32 (5): p.182-184. 1995.
In a trial on light grey pseudopodzolic soil in 1988-90, Lotus
corniculatus and Dactylis glomerata were grown separately
or in 75/25, 50/50 or 25/75% mixtures and cut for hay at the beginning
of flowering of L. corniculatus and heading of D. glomerata.
In the 1st year the 50/50% mixture gave the highest DM yield (4.74
t/ha); the other variants yielded up to 7.5% less. The stands
nominally containing 100 or 75% L. corniculatus had >50%
by weight of forbs in the 1st year, but this later decreased somewhat.
In the 2nd year L. corniculatus sown alone gave the lowest
yield (14.9 t/ha) and its 75/25% mixture with D. glomerata
gave the highest yield (17.83 t), followed by the 25/75% mixture
which yielded 17.48 t. In 1990, DM yields ranged from 9.18 t in
D. glomerata sown alone (then about 25% forbs) to 11.60
t in L. corniculatus sown alone (then about 45% forbs).
As the percentage of D. glomerata increased, CP content
and CP yield and Ca content decreased and CF and ash contents
increased.
Study of the influence of foliar nutrition with boron on seed
productivity of birdsfoot trefoil. Kyuchukova, A.; Radeva,
V. Rasteniev"dni Nauki vol. 32 (5): p.172-174. 1995.
In a field trial on leached chernozem containing 0.05 g B/100
g soil, Lotus corniculatus was sprayed with 250 g B/ha
at flowering and seed filling or with 500 g B at one or both of
these stages. Average seed yield in 1990-91 increased from 335
and 353 kg/ha in dry and wet controls, respectively, to 424-434
kg with 2 B applications and 389-400 kg with one application.
Two applications of 250 g B were most profitable. Numbers of pods/stem
and seeds/pod were highest with 2 applications of 500 g B/ha;
1000-seed weight was highest with 1 or 2 applications of 500 g.
Sowing method for smooth bromegrass cv. Nika for seed production.
Tomov, P. Rasteniev"dni Nauki vol. 32 (5): p.141-143. 1995.
In trials on leached chernozem in 1989-92, Bromus inermis
cv. Nika was sown in rows 30 or 60 cm apart or in bands 45 cm
apart, alone or alternating with rows of Lotus corniculatus
or Medicago sativa, or in rows 15 cm apart. alone or
mixed with each legume. No seed was harvested in the 1st year.
Seed yields in 1990-92 were highest in pure stands with inter-row
cultivation and averaged 1040, 986, 991 and 831 kg/ha at spacings
of 60, 45, 30 and 15 cm, respectively. At a given spacing, growing
B. inermis in alternate rows with L. corniculatus and
M. sativa reduced its seed yield by about 10-15 and 50%, respectively.
In mixed rows, seed yields were reduced by about 30-40%. Because
of the cost, growing seed crops in rows 60 cm apart, with inter-row
cultivation, is only recommended for production of elite or super-elite
seed. For mass seed production, the use of pure stands in rows
30 cm apart is recommended. Forage yields were highest with alternate
or mixed rows of M. sativa and hay yields from pure stands
of B. inermis.
Interrelations between the species in perennial grass mixtures
used as pastures. Videva, M. Rasteniev"dni Nauki vol.
32 (5): p.122-125. 1995.
In a trial on cinnamon meadow soil in 1987-91, Lotus corniculatus,
Festuca arundinacea and Dactylis glomerata were grown
in pure stands or in 30/70% mixtures of L. corniculatus
with each of the grasses. Lolium perenne, alone or with
L. corniculatus, was grown in 1988-91. Total annual DM
yield from 4 cuts ranged from 4.74 t/ha in L. perenne (184
d) to 8.22 t in L. corniculatus (145 d). The mixtures yielded
7.03-7.49 t. The rate of development and dynamics of DM accumulation
of D. glomerata made it most compatible with L. corniculatus.
F. arundinacea inhibited the growth of L. corniculatus
in the 1st year.
Effect of mineral fertilizer application on the yield and botanical
composition of meadow grasses and grass mixtures in the Troyan
region. Lingorski, V.; Totev, T.; Mukhovski, Ts.; Tankov,
K.; Churkova, B.; Georgieva, D.; Belperchinov, K. Rasteniev"dni
Nauki vol. 32 (5): p.100-103. 1995.
In field trials on infertile acid soil in 1989-92, Lotus corniculatus,
Trifolium pratense, T. repens, Dactylis glomerata, Festuca rubra
and Lolium perenne were grown in pure stands or in
mixtures for grazing or hay, and were given 80, 160 or 240 kg
N/ha alone or with 80 kg P2O5 + 80 kg K2O/ha. The legumes and
the pasture mixture showed little response to N. Yields of D.
glomerata, F. rubra and L. perenne were increased by
5-90, 44-84 and 66-134%, respectively. The highest yield of 13
t DM/ha was obtained from D. glomerata with 240 kg N +
PK. Applying PK alone had little effect on the grasses, but increased
T. repens yield by 41%. Effects on botanical composition
are reported; N stimulated growth of grasses and weeds, while
PK promoted legumes and suppressed weeds.
Effect of temperature and moisture potential on germination
and emergence in Lotus sp. Blumenthal, M.J.; Aston,
S.C.; Pearson, C.J. Australian Journal of Agricultural Research
vol. 47 (7): p.1119-1130. 1996.
Two controlled cabinet experiments compared the germination of
6 Lotus genotypes over a range of temperatures (0-40 deg
C) and moisture potentials (0 to -1.2 MPa). In addition, a field
experiment conducted at Berry, New South Wales (NSW), compared
the emergence of 5 Lotus genotypes over 18 sowing dates
at a range of soil temperature and moisture potentials. Lotus
corniculatus cv. Grasslands Goldie and L. uliginosus
cv. Grasslands Maku, G4703, G4704 and Sharnae were included in
both the controlled cabinet and field experiments, while Lotus
suaveolens CPI 35903 was included in the controlled cabinet
experiments only and Trifolium repens cv. Haifa was included
as a control in the field study. Of the commercially available
Lotus cultivars, Grasslands Goldie provided the greatest
flexibility in terms of sowing date in coastal NSW and could be
successfully sown even in late autumn and winter as it exhibited
the lowest base temperature for germination and field emergence.
Cultivars G4703, Sharnae and G4704 had a lower base moisture potential
for germination than the other 3 Lotus genotypes, but this
was not translated in to a higher percentage seedling emergence
in the field. L. suaveolens had an extremely low base temperature
for germination (1 deg C) compared with Grasslands Maku (6.4 deg
C) and it is suggested that hybridization of this species with
both L. corniculatus and L. uliginosus may result
in germplasm capable of germinating better at low temperature
and able to maintain the perenniality, rhizomatous habit and the
condensed tannin content of L. uliginosus.