RECENT LITERATURE
Seed pod shattering in the genus Lotus (Fabaceae): a
synthesis of diverse evidence. Grant, W. F. Canadian Journal
of Plant Science 76 (3): p.447-456. 1996.
Birdsfoot trefoil (Lotus corniculatus L.) is a perennial
dehiscent species with an indeterminate growth habit. Pod shattering
(shedding) has been a major problem, seed loss was high due to
continuous flowering and time of pod maturity. The anatomy of
the pod plays a role in pod shattering. A change in the orientation
of pericarp cells, unequal swelling and shrinkage occurs, and
a lower lignification of the mesocarp were considered major causes
of shattering. The relative humidity (RH) at the time of harvest
was also a major factor. The critical RH for dehiscence varied
with genotypes between 35 and 49%. There was no correlation for
pod dehiscence between plants grown to maturity under greenhouse
conditions and the same plants grown in the field. Management
practices (time of harvest, clipping early in the season, misting,
mowing and turning the windrow during drying, and desiccants)
were not successful in controlling pod shattering. Shattering
resistance is highly heritable and is considered to be controlled
by more than one gene in Lotus. Breeding to reduce shattering
through recurrent selection was unsuccessful. Attempts to transfer
the indehiscent seed pod trait from distantly related indehiscent
species via interspecific hybridization, diploid bridge species,
amphidiploidy, and backcrossing to birdsfoot trefoil, or similarly
by interspecific somatic hybridization, have shown promise. The
molecular approach has so far not been attempted but since genetic
transformation can be carried out in Lotus, this avenue
should be investigated.
Inclusion of dallis grass (Paspallum dilatatum, Poir)
in pastures. 2. Effects on nutritve value. <Original>
Inclusion de pasto miel (Paspalum dilatatum Poir) en pasturas.
2. Efecto sobre el valor nutritivo. Acosta, G.; Deregibus, V.
A.; Hammer Aldatz, R.. Revista Argentina de Produccion Animal.1996.
16:157-167.
The forage quality of different sward mixtures in the mesothermic
grasslands of the Humid Pampas in Argentina was studied. Nine
treatments were used: 3 sward mixtures (Lolium perenne + Trifolium
repens; Phalaris aquatica + Trifolium pratense; Festuca arundinacea
+ Lotus corniculatus) with different proportions of dallis
grass (0, 25 and 50%). Total density was 66 plants/m2. Defoliation
frequency in the warmest months was determined by dallis grass
phenological development, preventing it from exceeding 5% flowering
with a stubble of 3 cm. Defoliation frequencies for the remainder
of the year were determined by temperate species development.
Dallis grass inclusion had no effect on forage quality during
the cold months but increased NDF and ADF during the warmest months,
with no differences between the varying proportions of dallis
grass. Lower protein concentrations were observed in swards that
included dallis grass. Although results show a reduction in forage
quality caused by dallis grass inclusion, during the warmer period
forage production increased by 45%, 80% of which was attributed
to dallis grass. The digestible DM production of pastures was
higher, at least doubling summer forage production of pastures
that did not include this species. It is concluded that combining
dallis grass with other mesophytic species in pastures contributes
to increasing production and distribution of forage quality, without
diminishing it during the cooler months.
Mechanisms of Pinus radiata growth suppression by some
common forest weed species. Richardson, B.; Vanner, A.; Ray,
J.; Davenhill, N.; Coker, G. New Zealand Journal of Forestry
Science.1996. 26:421-437.
In a trial carried out adjacent to the New Zealand Forest Research
Institute nursery at Rotorua, which was designed to quantify the
reduction in Pinus radiata growth caused by a range of
weed species, tree seedlings were grown weed-free plots (treated
by mechanical cultivation and herbicide application) or with herbaceous
broadleaves (a volunteer mixture of species from which grasses
were excluded), Cytisus scoparius (broom), Ulex europaeus
(gorse), Buddleja davidii (buddleia), Holcus lanatus
(Yorkshire fog) with Lolium multiflorum (Italian ryegrass)
- the 'grass' treatment, Lotus uliginosus (lotus), or
Cortaderia selloana (pampas). Water and nutrient levels
were varied by factorial irrigation and fertilizer treatment (a
regime including NPK fertilizer and other treatments pre- and
post-planting). After 3 years tree stem volume was greatest in
weed-free, lotus, gorse, and grass treatments and least with buddleia
and pampas. The effect of herbaceous broadleaves and broom was
intermediate. It was concluded that tall, fast-growing, weed species
reduced P. radiata growth by restricting light availability
to tree crowns. No convincing evidence was found to link the large
growth losses with interference in water or nutrient supply.
The morphology and development of Lotus uliginosus and
Trifolium subterraneum under Pinus radiata canopy in
southern Chile. Balocchi, O. A.; Phillips, C. J. C. Agroforestry
Systems. 1997. 37:15-26.
A split-plot experiment was conducted in southern Chile to study
the effects of tree cover and level of fertilizer application
(30 kg/ha N + low or high dosages of P, K, Ca and S) at establishment
on the morphology and development of the legumes Lotus uliginosus
and Trifolium subterraneum, when sown in conjunction with
Festuca arundinacea as the companion grass. Trees were
13-year-old Pinus radiata, spaced at 4x12.5 m intervals
and with a mean canopy diameter of 4.8 m. At 150 days after sowing,
the total area of Lotus leaves and length of Lotus
stems/plant were not affected by tree cover. Individual plants
had fewer stems but they were longer. For Trifolium, despite
large increases in individual petiole length and leaf area, total
petiole length and leaf area/plant were reduced by tree cover
because of a reduced number of petioles/plant. At 275 days after
sowing, the number and weight of Lotus components/ha was
not affected by tree cover, although companion grass development
was reduced. By 640 days the number and weight of Lotus
components/ha was reduced, but only to the same degree as the
companion grass. Trifolium plant development, and in particular
seed yield, was affected by tree cover at 275 and 640 days and
to a greater extent than Lotus or the companion grass.
A high level of fertilizer application at establishment induced
a greater development of both legumes at 275 days, but by 640
days the effects were much reduced. It is concluded that both
Lotus uliginosus and Trifolium subterraneum respond
to tree cover by increasing stem length and leaf area, but that
in situations with low soil fertility, the development of Lotus
is less affected by tree cover than Trifolium.
Grazing and fertilizer management for establishment of Lotus
uliginosus and Trifolium subterraneum under Pinus
radiata in southern Chile. Balocchi, O. A.; Phillips,
C. J. C. Agroforestry Systems. 1997. 37:1-14.
An experiment was conducted in southern Chile to study the effect
of tree cover (0 or 200 stems of 13-yr-old Pinus radiata/ha),
grazing severity (8 or 12 cm height at commencement of grazing
by sheep) and fertilizer application rate (N at 30 kg/ha + low
or high dosages of P, K, Ca and S) on the establishment and growth
of Lotus uliginosus and Trifolium subterraneum,
when sown in conjunction with Festuca arundinacea. The
establishment of both legumes was greater in the agroforestry
system than in the open field, and the percentage of viable seeds
that were established was greater for Trifolium than Lotus.
Festuca established better when sown in conjunction with Lotus
in the open field. During the 2 yr after stand establishment there
was a greater reduction in the ground cover and dry matter (DM)
yield of both legumes, but in particular Trifolium, in
the agroforestry system than in the open field. In the second
year of grazing Trifolium contributed less than 9% of total
DM yield in the agroforestry system, compared with 22% for Lotus.
The ground cover of Lotus was increased by a tall grazing
height in the agroforestry system, whereas Trifolium increased
its cover when the grazing height was short. Additional fertilizer
at establishment had a greater effect in increasing herbage yield
in the open field than in the agroforestry system. It is concluded
that both Lotus and Trifolium establishments are
greater in an agroforestry system than in an open field, but that
in the agroforestry system there is a reduction in legume yield
over time, particularly of Trifolium.
Research strategy in solving problems on extending the nitrogen
fixation ability to major neoleguminous plants 1. Molecular genetic
approaches to symbiotic nitrogen fixation using Lotus japonicus.
Kawaguchi, M. Japanese Journal of Soil Science and Plant
Nutrition 1998 p.310-315.
Dry matter production, growth characteristics and nutritive
value of wild birdsfoot trefoil. Shin ChungNam Journal of
the Korean Society of Grassland Science 1998. p.129-132.
A wild Lotus corniculatus genotype and L. corniculatus
cv. Au Dewey were field sown at Keongsan, Keongbuk in the spring
of 1996. Emergence for Au Dewey was better than for wild L.
corniculatus, but flowering dates were similar. Regrowth of
Au Dewey was better than that of the wild genotype at each harvesting.
After the last harvesting date, October 1, there was no regrowth
of the wild genotype, but regrowth of Au Dewey measured 10cm.
Weed infestation in the wild birdsfoot trefoil plots was higher
than in the Au Dewey plots. DM yields were significantly higher
for Au Dewey than for the wild genotype.
Soluble acid invertase activity in leaves is independent of
species differences in leaf carbohydrates, diurnal sugar profiles
and paths of phloem loading. Kingston-Smith, A. H.; Galtier,
N.; Pollock, C. J.; Foyer, C. H. New Phytologist 1998. p.283-292
Leaf sucrose, starch, hexose and maximum extractable soluble acid
invertase activity were compared throughout the day in source
leaves of 13 plant species chosen for their putative phloem-loading
type (apoplastic or symplastic). Four species which represent
the different phloem-loading types (tomato line 3815-13, barley
cv. Pipkin, maize cv. Maris Jade and Fuchsia hybrida cv.
Rose Winston) were studied in detail. Acid invertase activity
was relatively constant throughout the day in all species. The
extent of sucrose, hexose and starch accumulation and the sucrose:starch
ratio measured at a given time were species-dependent. No correlations
were found between foliar soluble acid invertase activity and
the hexose, sucrose or starch content of the leaves in any of
the species, regardless of phloem-loading type. The species examined
could be divided into three distinct groups: (1) high sucrose,
low invertase (grapes cv. Chardonnay and Populus); (2) low sucrose,
low invertase (peas, Fuchsia hybrida, Saintpaulia ionantha,
Pelargonium zonale cv. Cardinal, Lotus corniculatus,
maize and tobacco); and (3) low sucrose, high invertase (tomatoes,
Lotus japonicus and Hydrangea macrophylla cv. Europe).
The absence of an inverse relationship between leaf sucrose, hexose
or starch contents and endogenous soluble acid invertase suggests
that this enzyme is not directly involved in carbon partitioning
in leaves but serves an auxiliary function.
Tracing the path of oxygen into birdsfoot trefoil and alfalfa
nodules using iodine vapor. Jacobsen, K. R.; Rousseau, R.
A.; Denison, R. F. Botanica Acta 1998. p.193-203.
Iodine vapour and its reaction with starch were used to trace
gas-phase pathways into the infected zone of determinate birdsfoot
trefoil (Lotus corniculatus) cv. Broadleaf and indeterminate
alfalfa (Medicago sativa) cv. Yolo root nodules. Histochemical
methods were used to identify suberized or lignified layers that
could act as barriers to gas diffusion. Birdsfoot trefoil nodules
were surrounded by a suberized periderm, but non-suberized cells
and intercellular spaces were observed in the periderm between
lenticels and their associated vascular bundles. Iodine entered
birdsfoot trefoil nodules only through lenticels. The periderm
appeared to provide a significant barrier to gas diffusion. Although
air spaces were rare in the nodule parenchyma (the inner cortex),
there was some evidence that a few air-filled pathways crossed
this secondary barrier, also in the vicinity of vascular bundles.
Alfalfa nodules were cylindrically surrounded by a suberized endodermis
which ended near the meristematic tip. Iodine entered principally
at the end of the endodermis near the meristem.
Persistence and productivity of pasture legumes in the cool-sub-tropical
grassland of Himachal Himalayas. Katoch, D. C. Range Management
& Agroforestry 1996. p.123-127.
Five temperate pasture legumes and two tropical legumes were evaluated
in Imperata cylindrica-dominated grasslands (1300 m alt.)
in Himachal Pradesh. The temperate legumes Trifolium pratense,
T. repens and Lotus corniculatus persisted well on
acidic soils with low P availability and toxicity of Fe and Al.
The tropical legumes Neonotonia wightii and Macrotyloma
axillare showed poor growth during the establishment year,
while among the temperate legumes T. ambiguum had poor
establishment and regeneration. It is suggested that T. pratense
is suitable for a cut and carry system and T. repens and
L. corniculatus cv. G-32 and G-46 for pasture.
Sugar content and palatability of some grass and legume species.
Original> Zuckergehalt und Schmackhaftigkeit einiger Gras-
und Kleearten in Reinsaat. Barcsak, Z.; Kispal, T.; Szeman, L.;
Tasi, J. Document Title> Zbornik predavanj posvetovanja o prehrani
domacih zivali "zadravcevi-erjavcevi dnevi", Radenci,
Slovenia, 27-28 oktober 1997. <Editors> Pen, A. Fakultat
fur Agrarwissenschaften, Landwirtschaftliche Universitat Godollo,
H-2103, Hungary. Zivinorejsko-veterinarski Zavod za Pomurje Zbornik
predavanj posvetovanja o prehrani domacih zivali "zadravcevi-erjavcevi
dnevi", Radenci, Slovenia, 27-28 oktober 1997. p.73-82.
In a field trial, 9 grass and 3 legume species and one grass mixture
were given 0, 100 or 200 kg N/ha. Sugar content of grasses decreased
with increasing N rate, but that of legumes showed little effect
of N rate. The Phleum pratense/Poa pratensis/Lolium perenne
mixture was the most palatable to cattle, followed by Lotus
corniculatus.
Selected soil factors and copper content in meadow vegetation.
Ostrowska, E. B. Original> Wybrane czynniki glebowe a zawartosc
miedzi w roslinnosci lakowej. Instytut Melioracji i Uzytkow Zielonych
w Falentach, 05-090 Raszyn, Poland. Wiadomosci Instytutu Melioracji
i Uzytkow Zielonych. 1997. p.93-103.
Cu contents were determined in 30 species from each of 2 meadows
on degraded chernozem at Falenty and the specific species coefficient
(SSC, the ratio of the content in the given species to that in
all the species collected) was calculated for each. Cu contents
ranged from 4.2 to 47.0 p.p.m. The highest SSC values were found
in Equisetum sp. (1.35-2.48), Carex vulpina (1.22-1.33),
Urtica dioica (1.15-1.26) and Ranunculus acer (R.
acris)(1.13-1.55). Values >1.25 also occurred in Achillea
millefolium, Potentilla anserina, Lotus corniculatus, Alopecurus
pratensis and Bromus mollis (B. hordeaceus).
Plant and soil Cu contents were also determined in meadows on
mineral soil in the Obra valley and the Zulawy Wislane. Sward
Cu contents were 3.8-10.0 and 5.4-11.4 p.p.m. at the 2 sites,
respectively. Average contents in grasses were slightly lower
and those in Taraxacum officinale and A. millefolium
considerably higher than in the sward as a whole. Forage Cu content
depended on soil pH and organic matter and P contents, but could
not be predicted from soil Cu content.
Two ineffective-nodulating mutants of Lotus japonicus-different
phenotypes caused by the blockage of endocytotic bacterial release
and nodule maturation. Imaizumi-Anraku, H. ; Kawaguchi, M.;
Koiwa, H.; Akao, S.; Syono, K. Plant and cell physiology. 1997.
v. 38 (7):871-881.
Mutants defective in nodule development and nitrogen fixation
of Lotus japonicus B-129 'Gifu' were obtained by induced
mutagenesis with EMS (ethylmethane sulfonate) treatment. Using
a symbiont of L. japonicus, Rhizobium loti JRL501,
17,000 M2 seeds were screened for plants affected in their symbiotic
phenotype, resulting in the successful isolation of eleven stable
mutants. In this paper, we report two ineffective nodulating mutants
among them. Reciprocal crossing between wild type 'Gifu' and these
mutants indicated that their phenotypes are under monogenic and
recessive control. Furthermore, tests for allelism with these
mutants showed that the mutated genes are non-allelic. Ultrastructural
analysis revealed that these mutants were inhibited at different
stages of nodule development and maturation. Based on histological
characteristics of the nodules, two ineffective nodulating mutants
were named alb1 (aberrant localization of bacteria inside nodule)
and fen1 (fail in enlargement of infected cells), respectively.
In the nodules of alb1, most of the bacteria failed to invade
the cytoplasm of cortical cells and were tightly confined inside
infection threads or localized in intercellular spaces of nodules.
Following prolonged inoculation, alb1 mutant also formed pale-pink
colored nodules with a low frequency, in which bacteria differentiated
into bacteroid and fixed nitrogen normally. Although the infected
cells in the nodules of fen1 mutant contained numerous differentiated
bacteroids, they failed to enlarge by cell expansion and showed
a low activity of nitrogen fixation.
Effect of oxygen availability on nitrogen fixation by two Lotus
species under flooded conditions. James, E.K. ; Crawford,
R.M.M. Journal of experimental botany. 1998. v. 49 (320):599-609.
The pasture legumes Lotus uliginosus (Schk.) and Lotus
corniculatus (L.), known to differ in their tolerance to flooding,
were inoculated with Rhizobium loti and flooded for 60
d while subjected to two levels of dissolved pO2: 0.241 and 0.094
micromoles ml-(-1). L. uliginosus showed significantly
greater growth (shoot and root) and N2 fixation under both pO2s,
compared to L. corniculatus, although growth and N2 fixation
by L. corniculatus was not affected by the low pO2. Surprisingly,
in L. uliginosus., growth, nodulation and N2 fixation were
all increased by low pO2 while nodulation of L. corniculatus
was unaffected by low pO2. The highest rates of endogenous ethylene
production were found with L. corniculatus where low pO2
plants showed a significant increase over that of the higher pO2
plants while L. uliginosus plants showed a decline. Root
porosity of L. uliginosus doubled in the low pO2-treatment
from a mean of 14.5% in high pO2 roots to 28.5%, whereas that
of L. corniculatus was relatively unaffected by pO2, being
7% and 9% for high and low pO2 plants, respectively. The structure
of nodules differed little between species and treatments, although
nodules/nodulated roots from the L. uliginosus plants had
particularly profuse lenticels and aerenchyma. However, L.
corniculatus nodules, especially those grown in the lower
pO2 showed signs of early senescence with vacuolation of infected
cells and green coloration when cut open. Leghaemoglobin (Lb)
concentrations in nodules from both species were unaffected by
low pO2, although that of L. corniculatus nodules, regardless
of pO2, was significantly greater than L. uliginosus. Concentrations
of the intercellular glycoprotein recognized by the monoclonal
antibody MAC265 were significantly reduced in nodules from the
low pO2 treatment in both species. Immunogold labelling showed
that the MAC265 antigen was localized primarily within intercellular
spaces within nodule cortices from both Lotus species.
A marked decrease in deposition of the MAC265 antigen within the
cortices of L. uliginosus nodules grown in the lower pO2.
is discussed in terms of the relative abilities of the two Lotus
spp. to maintain an O2 supply to the N2-fixing bacteroids within
submerged nodules.
Organization and expression of genes in the genomic region
surrounding the glutamine synthetase gene Gln1 from Lotus japonicus.
Thykjaer, T. ; Danielson, D.; She, Q.; Stougaard, J. Molecular
& general genetics : 1997. v. 255 (6):628-636.
Host range and distribution of the clover root-knot nematode,
Meloidogyne trifoliophila. Bernard, E. C.; Jennings,
P. L. Journal of Nematology 1997. V 29:662-672.
The ability of M. trifoliophila to gall 230 species and
cultivars of plants was determined in a greenhouse. All clovers
(Trifolium spp.) were severely galled regardless of species
or cultivar. Most soyabean cultivars were moderately to severely
galled. Among other legumes, faba beans, garden pea, Lespedeza
stipulacea, Melilotus indica and Vicia sativa
were good hosts, but lucerne, Lotus corniculatus, peanut
and Phaseolus vulgaris were poor or non-hosts. Among other
plant families, most Apiaceae (Umbelliferae) and Brassicaceae
(Cruciferae) were galled, but Cucurbitaceae, Iridaceae, Malvaceae,
Poaceae and Solanaceae were rarely or never galled. Results for
Amaryllidaceae, Asteraceae, Lamiaceae and Liliaceae were variable.
This nematode was not found in a survey of pasture and soyabean
fields in southwestern Tennessee.
Genetic manipulation of condensed tannins in higher plants.
II. Analysis of birdsfoot trefoil plants harboring antisense dihydroflavonol
reductase constructs. Robbins, M. P.; Bavage, A. D.; Strudwicke,
C.; Morris, P. Plant Physiology. 1998. V 116:1133-1144.
Transgenic birdsfoot trefoil (Lotus corniculatus) plants
harbouring antisense dihydroflavonol reductase (dihydrokaempferol
4-reductase) (AS-DFR) sequences were produced and analysed. In
initial experiments the effect of introducing three different
antisense Antirrhinum majus DFR constructs into a single
recipient genotype (S50) was assessed. There were no obvious effects
on plant biomass, but levels of condensed tannins showed a statistical
reduction in leaf, stem and root tissues of some of the antisense
lines. Transformation events were also found, which resulted in
increased levels of condensed tannins. In subsequent experiments
a detailed study of AS-DFR phenotypes was carried out in genotype
S33 using pMAJ2 (an antisense construct comprising the 5' half
of the A. majus cDNA). In this case, reduced tannin levels
were found in leaf and stem tissues and in juvenile shoot tissues.
Analysis of soluble flavonoids and isoflavonoids in tannin down-regulated
shoot tissues indicated few obvious default products. When two
S33 AS-DFR lines were outcrossed, there was an underrepresentation
of transgene sequences in progeny plants and no examples of inheritance
of an antisense phenotype were observed. This is the first report
of the genetic manipulation of condensed tannin biosynthesis in
higher plants.
Notes on the biology and phenology of Zygaena (Zygaena)
filipendulae (Linnaeus, 1758) and Z. (Z.) trifolii
(Esper, 1783) (Lepidoptera: Zygaenidae) in Cornwall. Tremewan,
W. G. Entomologist's Gazette. 1998. V 49:91-97.
Details of observations made in 1997 of Z. filipendulae, Z.
trifolii and Z. trifolii decreta in Cornwall (at Boskednan,
near Redruth, St. Agnes Head, Constantine Bay, St. Michael's Mount,
Church Cove, and Porkellis), UK, are listed. The larvae of all
3 species were observed feeding on Lotus corniculatus and
L. uliginosus. The emergence dates and food plants are discussed
in relation to previous sightings in Cornwall.
The water use efficiency of annual and perennial forage species
in low elevation grasslands. Karatassiou, M.; Noitsakis, B.;
Koukoura, Z. Breeding for a multifunctional agriculture. Proceedings
of the 21st Meeting of the Fodder Crops and Amenity Grasses Section
of EUCARPIA, Kartause Ittingen, Switzerland, 9-12 September 1997.
<Editors> Boller, B.; Stadelmann, F. J. 1998. p.70-72.
The relationship between water use efficiency (WUE) and leaf water
potential (LWP) was studied in two annual (Medicago minima,
Avena fatua) and two perennial (Lotus aegaeus, Chrysopogon
gryllus) forage species in a low elevation grassland of North
Greece. In the early part of the growing season (vegetative growth),
the annuals had higher WUE than the perennials at similar LWP,
associated with higher stomatal conductance. During reproductive
growth, however, the WUE was higher in perennials than in the
annuals. It is suggested that growing annuals and perennials in
mixture should maintain forage supply throughout the growing season.
Production potential of mountain meadows. Kasperczyk, M.
Ecological and biological aspects of fodder crop production. Refereed
papers from an international research conference held at Nitra,
Slovakia, 23 October 1997. <Editors> Gregorova, H.; Jancovic,
J.; Babel'ova, M. p.118-121.
The potential productivity of mountain meadows (600-650 m alt.)
was investigated in studies in 1987-95 in Poland. Grassland improvement
techniques included partial or complete resowing with Dactylis
glomerata, Phleum pratense, Arrhenatherum elatius, Trifolium pratense
or Lotus corniculatus. The meadows were given no fertilizers,
60 or 90 kg P, 100 or 120 kg K, and 90, 180 or 270 kg N. Two cuts
were taken at the lower fertilizer rates and 3 at the higher rates.
The unimproved grassland was a Festuca pratensis/Poa pratensis
sward. The productivity of the unimproved grassland exceeded that
of the improved grassland at all fertilizer rates (maximum yield
at the highest fertilizer rates was 8.61 t dry matter/ha with
3 cuts). Two cuts/year were recommended.
Biomass and compositional changes occur in chalk grassland
turves exposed to elevated CO2 for two seasons in FACE. Warwick,
K. R.; Taylor, G.; Blum, H. Global Change Biology. 1998. v
4(4) p.375-385
Gene discovery in legume nodulation: from soybean to Lotus
japonicus. Gresshoff, P.M. ; Stiller, J.; Jiang, Q.; Men,
A.; Landau-Ellis, D.; Chian, R.J.; Ghassemi, F.; Pillai, S.; Radutoiu,
S.; Limami, A. In: Biological nitrogen fixation for the 21st
century : proceedings of the 11th International Congress on Nitrogen
Fixation, Institut Pasteur, Paris, France, July 20-25, 1997, p.
303-304.
Small GTP-binding proteins in Lotus japonicus. Jensen,
T.J. ; Borg, S.; Poulsen, C. In: Biological nitrogen fixation
for the 21st century : proceedings of the 11th International Congress
on Nitrogen Fixation, Institut Pasteur, Paris, France, July 20-25,
1997, p. 231-232.
Rhizomatous Lotus corniculatus L. III. Introgression
of rhizomes into autogamous germplasm. Nualsri, C. ; Beuselinck,
P.R.; Steiner, J.J. Crop science. 1998. v. 38 (2), p. 503-509.
Introduction of genes for rhizomes from wild Lotus corniculatus
L. germplasm into domesticated germplasm may be an important step
towards improving persistence of cultivated L. corniculatus,
normally a cross-pollinated herbage crop. This study was initiated
to determine if rhizomes could be transferred to a L. corniculatus
germplasm that sexually reproduces via autogamy. Autogamy is an
unusual reproductive expression in this typically self-incompatible
species. Compatibility was high between the autogamous germplasm
AG-S4 and five wild Moroccan accessions with rhizomes. Higher
crossing success was obtained when AG-S4 was used as a maternal
parent. Most seeds produced were normal in appearance and size
and had high germination. The resulting F1 progeny were morphologically
intermediate between the parents for size and shape of leaf and
floral characters, but appeared more similar to their Moroccan
parents. Differences between reciprocal crosses were not evident.
Hybridity of progeny was confirmed by random amplified polymorphic
DNA (RAPD) analysis using eight primers. Fertility of F1 progeny
was low relative to their parents. Meiosis of parental genotypes
was characterized by a high frequency of bivalents, but the meiotic
behavior or their F1 hybrids was more irregular. The frequency
of univalents varied from 0 to 8 with an average 2.4 per cell,
indicating homology of chromosomes between AG-S4 and Moroccan
accessions was not complete. Rhizomes were successfully expressed
in F1 hybrids and a small number were round to also be autogamous.
The autogamous hybrids will be important tools to elucidate the
inheritance of rhizomes in L. corniculatus. Selection among
the hybrids could lead to autogamous, rhizomatous cultivars of
L. corniculatus.
Facilitative effect of Lotus tenuis on Paspalum dilatatum
in a lowland grassland of Argentina. Quinos, P.M. ; Insausti,
P.; Soriano, A. Oecologia. 1998. v. 114 (3), p. 427-431.
Regulation of the plant aspartate aminotransferase P2 gene
during nodule development. Reynolds, P.H.S. ; Mett, V.; Vincze,
E.; Podivinsky, E. In: Biological nitrogen fixation for the 21st
century : proceedings of the 11th International Congress on Nitrogen
Fixation, Institut Pasteur, Paris, France, July 20-25, 1997, p.
235-236.
HAR1, an incomplete dominant mutation in Lotus japonicus,
confers aberrant root development and an unusual HyperNodulation
Response (HNR). Szczyglowski, K. ; Wopereis, J.; Dazzo, F.B.;
deBruijn, F.J. In: Biological nitrogen fixation for the 21st
century : proceedings of the 11th International Congress on Nitrogen
Fixation, Institut Pasteur, Paris, France, July 20-25, 1997, p.
305-306.
Research strategy in solving problems on extending the nitrogen
fixation ability to major neoleguminous plants 1. Molecular genetic
approaches to symbiotic nitrogen fixation using Lotus japonicus.
Kawaguchi, M. Japanese Journal of Soil Science and Plant Nutrition.
1998. V 69(3):.310-315.
Fusions between green fluorescent protein and beta -glucuronidase
as sensitive and vital bifunctional reporters in plants. Quaedvlieg,
N. E. M.; Schlaman, H. R. M.; Admiraal, P. C.; Wijting, S. E.;
Stougaard, J.; Spaink, H. P. Plant Molecular Biology. 1998.
V 37:715-727.
By fusing the genes encoding green fluorescent protein (GFP) and
beta -glucuronidase (GUS) a set of bifunctional reporter constructs
were created that are optimized for use in transient and stable
expression studies in plants. This approach makes it possible
to combine the advantage of GUS, its high sensitivity in histochemical
staining, with the advantages of GFP as a vital marker. The fusion
proteins were functional in transient expression studies in tobacco
using either DNA bombardment or potato virus X as a vector, and
in stably transformed Arabidopsis thaliana and Lotus
japonicus plants. The results show that high level of expression
does not interfere with efficient stable transformation in A.
thaliana and L. japonicus. Using confocal laser scanning
microscopy it was shown that the fusion constructs are suitable
for promoter expression studies in all organs of living plants,
including root nodules. The use of these reporter constructs in
the model legume L. japonicus offers possibilities for
the study of the root nodulation process.
The Lotus japonicus LjNOD70 nodulin gene encodes a protein
with similarities to transporters. Szczyglowski, K.; Kapranov,
P.; Hamburger, D.; Bruijn, F. J. de. Plant Molecular Biology.
1998. V 37:651-661.
A novel nodule-specific gene, LjNOD70, associated with late stages
in L. japonicus nodule development and/or functioning was
characterized (GenBank accession number AF031243 and the related
expressed sequence tag (126K15) AF031244). The LjNOD70 gene is
a member of a small family of closely related L. japonicus
genes. Two major mRNA species corresponding to the LjNOD70
gene were identified in nodules and shown to be the result of
a mechanism resembling alternative splicing. The longer, presumably
unspliced, mRNA species was shown to contain a single open reading
frame (ORF), encoding a polytopic hydrophobic protein, LjN70,
with a predicted molecular mass of 70 kDa. The second, presumably
spliced, mRNA species was shown to be less abundant in nodules.
The absence of the presumptive 'intron' divided the reading frame
into an upstream and a downstream ORF encoding the partial N-
and C-terminal regions of the LjN70 protein, respectively. The
predicted amino acid sequence of nodulin LjN70 revealed structural
features characteristic of transport proteins, and shared similarity
with the oxalate/formate exchange protein of Oxalobacter formigenes.
It is proposed that the L. japonicus LjNOD70 gene family
encodes nodule-specific transport proteins, which may have evolved
as a result of exon-intron shuffling.
Estimates of heritability and genetic gain from selection for
lower condensed tannins in greater lotus (Lotus uliginosus
Schkuhr). Kelman, W. M. Journal of Genetics & Breeding.
1997. V51:235-238.
Condensed tannins (CT) are associated with bloat protection and
improved dietary utilisation of N in ruminants, but high concentrations
of CT (>40 g/kg of DM) can reduce feed intake and digestibility.
As greater lotus (L. uliginosus) generally has high levels
of CT, estimates of heritability for CT were derived from data
on CT content of 23 genotypes clonally replicated at 2 localities
and their half-sib progeny grown at 1 locality. Genotype x locality
interaction was important in clonal analysis, but rank correlation
suggested that low CT selections would retain this feature across
environments. Narrow-sense heritability estimates for CT were
approx equal to 0.50 and genetic gain from selection predictions
indicated that 50% more selection progress for lower CT could
be made from a combined family and within-family selection strategy
than from selection on a family-mean basis alone.
Genetic variation and gene flow in Alpine diploid and tetraploid
populations of Lotus (L. alpinus (D.C.) Schleicher/L.
corniculatus L.). I. Insights from morphological and allozyme
markers. Gauthier, P.; Lumaret, R.; Bedecarrats, A. Heredity.
1998. V 80:683-693.
The altitudinal distribution, morphology, phenology and allozyme
polymorphism at 12 loci were studied in diploid and tetraploid
populations of Lotus growing at over 1800 m in the French
Alps to clarify relationships between these cytotypes. In some
previous studies these diploid and tetraploid cytotypes have been
identified as the distinct species L. alpinus and L.
corniculatus, respectively. In general, diploids occurred
at higher elevation than tetraploids, although some sites at intermediate
elevation contained both cytotypes, diploids predominating in
the upper part and tetraploids in the lower part of the contact
area. Evidence for an autopolyploid origin of the tetraploids
was provided by tetrasomic inheritance at two enzyme loci, although
no tetravalents were observed at meiosis. Diploid and tetraploid
plants shared morphological traits distinct from those of other
Lotus species and showed differences in size, which may
be attributable to chromosome doubling. The diploid cytotype,
L. alpinus, may thus be the ancestor of the Alpine tetraploids.
Both cytotypes showed nearly identical suites of alleles at all
loci and very similar genetic parameters, except for heterozygosity,
which was higher in the tetraploid plants. However, the occurrence
of few alleles specific to each ploidy level indicated limited
gene flow between cytotypes, probably as a result of spatial segregation
and variation in flowering time. Of the individuals in a tetraploid
population, 25% showed morphological traits similar to those observed
in L. corniculatus, suggesting genetic introgression between
the two tetraploid species.
Genetic variation and gene flow in Alpine diploid and tetraploid
populations of Lotus (L. alpinus (D.C.) Schleicher/L.
corniculatus L.). II. Insights from RFLP of chloroplast DNA.
Gauthier, P.; Lumaret, R.; Bedecarrats, A. Heredity. 1998.
V 80:694-701.
RFLP of chloroplast DNA was studied in two diploid (2x) and five
tetraploid (4x) populations of Lotus alpinus in the French
Alps. This was compared with four non-Alpine populations and two
cultivars of Lotus corniculatus (4x) introduced to the
Alpine valleys. Based on the 13 site and 11 length mutations detected,
seven distinct haplotypes were identified, which clustered in
two groups, corresponding to the two Lotus species. With
only one exception, the diploid and the tetraploid L. alpinus
plants had the same haplotype. This is to be expected, because
morphological variation and tetrasomic inheritance suggest that
the tetraploids were derived from the diploids by autopolyploidy.
In L. corniculatus, two very similar haplotypes were found
in the natural very distant populations. In contrast, the chloroplast
DNA (ctDNA) haplotypes of the two cultivars differed considerably
from each other and were more related to those observed in L.
alpinus, suggesting that these cultivars may be derived maternally
from L. alpinus individuals. In one tetraploid L. alpinus
population, a single ctDNA haplotype was identified. As this haplotype
was related to those observed in the L. corniculatus group,
local genetic introgression may have occurred between 4x L.
alpinus plants and cultivated L. corniculatus.
Composted sawdust as a carrier for Bradyrhizobium, Rhizobium
and Azospirillum in crop inoculation. Kostov, O.;
Lynch, J.M. World journal of microbiology & biotechnology.
1998. v. 14:389-397.
Preliminary studies of the effects of pre-emergence herbicides
on the establishment of injurious weed and wildflower species.
Pywell, R.F.; Nowakowski, M.; Walker, K.J.; Barratt, D.; Sparks,
T.H. Weed seedbanks: determination, dynamics and manipulation.
23-24 March 1998, St. Catherine's College, Oxford, p. 173-178.
Nodule organogenesis and symbiotic mutants of the model legume
Lotus japonicus. Szczyglowski, K. ; Shaw, R.S.; Wopereis,
J.; Copeland, S.; Hamburger, D.; Kasiborski, B.; Dazzo, F.B.;
De Bruijn, F.J. de. Molecular plant-microbe interactions. 1998.
v. 11(7), p. 684-697.
A detailed microscopical analysis of the morphological features
that distinguish different developmental stages of nodule organogenesis
in wild-type Lotus japonicus ecotype Gifu B-129-S9 plants
was performed, to provide the necessary framework for the evaluation
of altered phenotypes of L. japonicus symbiotic mutants.
Subsequently, chemical ethyl methanesulfonate (EMS) mutagenesis
of L. japonicus was carried out. The analysis of approximately
3,000 M1 plants and their progeny yielded 20 stable L. japonicus
symbiotic variants, consisting of at least 14 different symbiosis-associated
loci or complementation groups. Moreover, a mutation affecting
L. japonicus root development was identified that also
conferred a hypernodulation response when a line carrying the
corresponding allele (LjEMS102) was inoculated with rhizobia.
The phenotype of the LjEMS102 line was characterized by the presence
of nodule structures covering almost the entire root length (Nod++),
and by a concomitant inhibition of both root and stem growth.
A mutation in a single nuclear gene was shown to be responsible
for both root and symbiotic phenotypes observed in the L. japonicus
LjEMS102 line, suggesting that (a) common mechanism(s) regulating
root development and nodule formation exists in legumes.
Soil acidification through carbon cycling in legumes: a pot
experiment examining the contributions from white clover, lotus,
caucasian clover, and lucerne. Monaghan, R. M.; Morrison,
J. D.; Sinclair, A. G. New Zealand Journal of Agricultural Research.
1998. V 41:243-250.
Soil acidification, induced by the growth of four legume species
(white clover (Trifolium repens), lotus (Lotus),
lucerne (Medicago sativa), or caucasian clover (Trifolium)),
was examined in a glasshouse pot trial at initial soil pH levels
of either 4.5, 5.0, or 5.5. White clover and lotus out-yielded
lucerne and caucasian clover at all soil pH levels, particularly
at the lowest level of pH 4.5. The acidity produced as a result
of this legume growth was shown to approximately correspond to
the removal of excess cation over anion nutrients by the plants.
Averaged over all three soil pH levels, plant excess cation concentrations
decreased in the order: white clover > caucasian clover >
lucerne > lotus. With the exception of white clover, there
was no evidence of any consistent change in excess cation concentrations
as soil pH decreased, indicating that the rate of excess cation
removal did not decrease as soil pH declined. Although white clover
was shown to have a higher excess cation concentration than the
other three legumes, plant yield was the major determinant of
legume-induced soil acidification, rather than legume species
excess cation concentration.
Lotus corniculatus nodulation specificity is
changed by the presence of a soybean lectin gene. Rhijn, P.
van; Goldberg, R. B.; Hirsch, A. M. Plant Cell. 1998. V 10:1233-1249.
Plant lectins have been implicated as playing an important role
in mediating recognition and specificity in the Rhizobium-legume
nitrogen-fixing symbiosis. To test this hypothesis, the soyabean
lectin gene Le1 was introduced either behind its own promoter
or behind the cauliflower mosaic virus 35S promoter into Lotus
corniculatus, which is nodulated by R. loti. Nodule-like
outgrowths developed on transgenic L. corniculatus plant
roots in response to Bradyrhizobium japonicum, which nodulates
soyabean and not Lotus spp. Soyabean lectin was properly
targeted to L. corniculatus root hairs, and although infection
threads formed, they aborted in epidermal or hypodermal cells.
Mutation of the lectin sugar binding site abolished infection
thread formation and nodulation. Incubation of bradyrhizobia in
the nodulation (nod) gene-inducing flavonoid genistein increased
the number of nodule-like outgrowths on transgenic L. corniculatus
roots. Studies of bacterial mutants, however, suggest that a component
of the exopolysaccharide surface of B. japonicum, rather
than Nod factor, is required for extension of host range to the
transgenic L. corniculatus plants.
Mycorrhiza mutants of Lotus japonicus define genetically
independent steps during symbiotic infection. Wegel, E.; Schauser,
L.; Sandal, N.; Stougaard, J.; Parniske, M. Molecular Plant-Microbe
Interactions. 1998. V 11:933-936.
Four nodulation mutants of L. japonicus affected in 3 different
genetic loci blocked infection by G. intraradices within rhizodermal
cells where abnormal deformations of hyphae occurred. Rare successful
infections led to the formation of arbuscules. It is suggested
that the affected plant genes are essential during the early infection
process, but are dispensable for later developmental stages.
Diurnal and seasonal osmotic potential changes in Lotus
creticus creticus plants grown under saline stress. Sanchez-Blanco,
M. J.; Morales, M. A.; Torrecillas, A.; Alarcon, J. J. Plant
Science (Limerick). 1998. V136: 1-10.
Lotus creticus creticus plants grown in a greenhouse were
exposed to 0, 70 and 140 mM NaCl for 4 months (September-December).
Salinity caused a reduction in total dry weight of Lotus plants
treated with 140 mM NaCl, whereas no significant effects on growth
were observed with 70 mM NaCl. Predawn leaf water potential and
predawn leaf osmotic potential showed constant values in control
plants during all experiment, whereas a decrease of both parameters
was observed between September and October for the saline treatments.
The relative contribution of passive (dehydration) versus active
mechanisms (osmotic adjustment) involved in seasonal leaf osmotic
potential changes were determined. Seasonal decreases of the osmotic
potential at full turgor in the treated plants showed the capacity
for osmotic adjustment by accumulation of Na+ and Cl-1, because
the accumulation of organic solutes due to salts was not consistent.
In plants treated with 70 mM NaCl, the seasonal changes of the
osmotic potential were produced by net solute accumulation, because
the dehydration contribution was negligible. In plants treated
with 140 mM NaCl, the seasonal changes of the osmotic potential
were caused by ion accumulation, but also by tissue dehydration.
At the end of the salinization period (December), a possible diurnal
adaptation in water relations was also considered. The dehydration
was the major mechanism involved in diurnal changes of leaf osmotic
potential, and only at the highest salinity level some diurnal
osmotic adjustment could be observed. In conclusion, the osmotic
adjustment in Lotus might be a beneficial trait when the
plants are treated with moderate levels of salinity (70 mM NaCl).
At higher salinity (140 mM NaCl), the high absorption and accumulation
of ions causes important toxic effects and induces leaf tissue
dehydration.
Study on the effectiveness of growing Lotus corniculatus
as an interplant crop in a hawthorn orchard. Ding YuChuan;
Yu XiaoQiou. China Fruits. 1998. 1:26-28.
Intercropping with L. corniculatus was investigated in
a hawthorn orchard with sandy soil (in Shanxi, China). Tree spacing
was 1 x 2 m, and L. corniculatus was sown in the row spaces.
Intercropping increased soil organic content by 27.6%, and soil
N, P and K increased by 3.3, 13.6 and 10.6%, respectively. Soil
temperature was reduced by 1.5 deg C. Hawthorn production, fruit
weight, and fruit pectin and ascorbic acid content increased under
intercropping.
Plant cold acclimation, hardiness, and winter injury in response
to bare soil and groundcover-based nursery field management systems.
Calkins, J.B.; Swanson, B.T. Journal of environmental horticulture.
1998. v. 16 (2), 82-89.
Soluble acid invertase activity in leaves is independent of species differences in leaf carbohydrates, diurnal sugar profiles and paths of phloem loading. Kingston-Smith, A.H.; Galtier, N.; Pollock, C.J.; Foyer, C.H. The New phytologist. 1998. 139:283-292.
Methods for establishing legumes on sandy soils. Rehm,
G.W.; Sheaffer, C.C.; Martin, N.P.; Becker, R.L. Journal of production
agriculture. 1998. 11:108-112.
Crop establishment is a major concern for producers who grow legumes
on sandy soils. This study was conducted on a Verndale sandy
loam (coarse-loamy, mixed Udic Argiboroll) to evaluate the impact
of five methods of establishment on the production of four legumes
(alfalfa [Medicago sativa L.], birdsfoot trefoil [Lotus
corniculatus L.], cicer milkvetch [Astragalus cicer
L.], red clover [Trifolium pratense L.]). Methods varied
from the use of a clean, prepared seedbed to no-till seeding into
small grain stubble. The study was initiated in 1991 and repeated
in 1992. Yields from spring seedings were measured in the year
of establishment. Dry matter yields were also measured for two
residual years following establishment. Stand counts were taken
in the fall of 1992. Yields of all legumes measured in the year
of establishment were generally higher when there was no competition
from a companion crop. In general, yields of alfalfa and red clover
were equal but higher than yields of birdsfoot trefoil and cicer
milkvetch when all establishment methods are considered. Stand
counts showed that all establishment methods produced an acceptable
stand of all legumes. Measured stand, however, was not directly
related to forage yield. The results of this study show that these
are several methods that can be used to successfully establish
legumes on sandy soils. Choices for individual forage producers
will be highly dependent on erosion potential and crops grown
for the total farming system.
Phytoextraction for soil remediation. Grath, S.P. In: Plants that hyperaccumulate heavy metals : their role in phytoremediation, microbiology, archaeology, mineral exploration and phytomining, p. 261-287.
Effect of the environment on the production of condensed tannins
in Lotus uliginosus Schkuhr (Fabaceae).<Original>
Influence de l'environnement sur la production de tanins condenses
chez Lotus uliginosus Schkuhr (Fabaceae).- Mansion, G.; Blaise,
S.; Braine, J. P.; Lacoste, A. Acta Botanica Gallica. 1997- 144:443-448.
The condensed tannin content and leaf area of 3 natural populations
of Lotus uliginosus, collected from more or less oligotrophic
hydromorphic soils in France, were compared to those of an experimental
population in pots. Pot plants were planted in an eutrophic or
oligotrophic soil, watered once or twice per day, and submitted
to simulated herbivory at 3 dates. L. uliginosus produced
more tannins and had smaller leaves in soils with low water and
nutrient availability (oligotrophic soils). Herbivory enhanced
tannin production on fertile soils.
Tolerance to herbicides of ground cover species for New Zealand
orchards. Harrington, K. C.; Rahman, A. Plant Protection Quarterly.
1998 13:111-116.
Herbicide tolerance studies were conducted on 8 species with potential
for ground cover use in New Zealand orchards. Festuca rubra
and F. longifolia tolerated a wide range of grass killing
herbicides and could be easily cleared of weeds. Weeds in Trifolium
repens could be controlled by haloxyfop, 2,4D, MCPA and glyphosate,
while paraquat, diquat, simazine and haloxyfop could be used in
Lotus pedunculatus (L. uliginosus) swards. Dichondra
micrantha was sufficiently tolerant of tribenuron, clopyralid,
glyphosate, glufosinate and paraquat/diquat to make it a suitable
cover crop. Hydrocotyle heteromeria and Centella uniflora
tolerated several knockdown herbicides. However, the range of
herbicides tolerated by Agrostis castellana would not allow
easy removal of grass weeds. The potential of cover crops in orchards
for weed control is discussed.
Polymorphism of two defence mechanisms in Lotus corniculatus L. (Fabaceae); relation with abiotic factors.<Original> Polymorphisme de deux mecanismes de defense chex Lotus corniculatus L. (Fabaceae); mise en relation avec des feateurs abiotiques.- Bazin, A.; Blaise, S.; Cartier, D. Acta Botanica Gallica. 1997. 144:433-442.
Effect of inoculation with Rhizobium loti and phosphorus
fertilization on Lotus tenuis mycorrhizal infection.<Original>
Efecto de la inoculacion con Rhizobium loti y la fertilizacion
fosfatada sobre la micorrizacion en Lotus tenuis. Andreoli,
Y. E.; Laich, F.; Quadrelli de Escuder, A. M.; Echeverria, H.
Ciencia del Suelo. 1997. 15:45-47.
An experiment was carried out on Lotus tenuis to determine
the effect of phosphate fertilizers and inoculation with Rhizobium
loti on spontaneous vesicular arbuscular mycorrhizas (VAM).
The experiment was sown in the Argentine Flooding Pampa on a sodic
soil as a randomized complete block design, with and without inoculation
with a selected strain of R. loti and 0, 11 and 22 kg P/ha.
Three plant samplings were made in which the VAM percentage was
determined. Neither interaction between inoculation and phosphate
levels, nor differences within inoculation treatments were detected
on VAM percentage. The significantly lower percentage of VAM with
increased levels of phosphorus showed that this nutrient diminished
VAM-lotus symbiosis, even for the lowest amount of phosphorus
added.
Response of Lotus tenuis Waldst to inoculation with
Rhizobium loti and phosphate fertilization.<Original>
Respuesta de Lotus tenuis Waldst a la inoculacion con Rhizobium
loti y a la fertilizacion fosfatada.- Quadrelli, A. M.; Laich,
F. S.; Andreoli, E.; Echeverria, H. E. Ciencia del Suelo. 1997.
15:22-27.
Lotus tenuis is found in the Argentine Flooding Pampa as
a naturalised species spontaneously nodulated and mycorrhized.
However, when it is artificially sown its developmental rate is
slow and its competitive aggressiveness is poor. To improve lotus
production on sown/artificial pastures it was hypothesized that
the symbiotic associations could be improved by an earlier and
more effective Rhizobium infection by the inoculation of
lotus with a selected strain of Rhizobium loti and the
addition of low doses of phosphate to promote absorption of phosphorus
that would not affect spontaneous mycorrhizas symbiosis. This
was tested in a field trial in a Natraquoll soil. Lotus was inoculated
with the selected strain 733 of R. loti and was fertilized
at sowing with 0, 11 and 22 kg P/ha. There was no interaction
between levels of phosphate and inoculation. Significant increases
in lotus dry matter and total nitrogen due to the Rhizobium
inoculation were found. The selected strain of Rhizobium
promoted an earlier nodulation and the strain showed a good saprophytic
performance. There was no response to dry matter production by
lotus to the added phosphate. However, phosphate fertilization
promoted weed growth and may have affected the lack of response
by lotus to phosphorus. The activity of mycorrhizas was depressed
by the Rhizobium inoculation treatment and the higher level
of phosphate.
Residual effect and phosphorus refertilization of pastures
in Entre Rios (Argentina).<Original> Efecto residual
y refertilizacion fosfatada de pasturas implantadas en entre rios
(Argentina).- Quintero, C. E.; Boschetti, N. G.; Benavidez, R.
Ciencia del Suelo. 1997. 15:1-5.
Experiments with triple superphosphate in pastures (Medicago
sativa, Lotus corniculatus and Festuca arundinacea)
were carried out to evaluate the residual effect of this fertilizer
when applied at sowing and the response to refertilization. The
experiments showed that total annual yield for the second and
third year was significantly related to the number of leguminous
plants per square metre, to P-Bray availability and to phosphorus
rate. Yield increased linearly to 6.5 t/ha up to a total of 200
legume plants/m2. Pastures showed a positive response to the residual
effects of the fertilizer only when the density of leguminous
plants surpassed 80 plants/m2. The soil test P-Bray 1 was calibrated
according to Nelson's and Anderson's method; fertility classes
were classified as low, medium and high and their class limits
were 5 and 14 mg P/kg. Fertilizer application (refertilization),
in rates of 8 to 16 kg/ha, produced a yield increase that varied
from 0.64 to 1.5 t/ha for low and medium class whereas no response
was observed for the highest class. Due to low stand of legumes
plants that survived in the third year, the residual effect of
sowing fertilizer was extended only until the second year. The
best result in three years was obtained with fertilization at
sowing, whereas refertilization in the second and third year did
not significantly increase total response. The effectiveness of
phosphorus fertilizer incorporated at sowing was higher than dividing
the same rate in two or three applications.
Rhizomatous Lotus corniculatus: IV. Inheritance of rhizomes.
Nualsri, C.; Beuselinck,: R. Crop Science. 1998. 38:1175-1179.
Rhizome production has been transferred from wild germplasm of
Lotus corniculatus (broadleafed birdsfoot trefoil) into
domesticated cultivars and autogamous germplasm. The objective
of this study was to determine the inheritance of rhizomes in
L. corniculatus. Crosses were made between AG-S4, an autogamous,
non-rhizomatous germplasm and two rhizomatous accessions from
Morocco, G31276 and G31317. Two autogamous progeny from each cross
(verified as F1 hybrids by morphological, meiotic and RAPD markers)
produced F2 seed and were reciprocally backcrossed (BC). After
40 wk growth in the greenhouse, F2 and BC progeny were scored
for rhizome production. Plants failing to express rhizomes in
the greenhouse were transplanted to the field at Columbia, Missouri,
USA and reevaluated for presence or absence of rhizomes at the
end of the growing season. Segregation ratios for rhizome expression
were tested for goodness-of-fit by the Chi-square ( chi 2) test.
The ratios of rhizome production in F2 and BCs to AG-S4 fit 3:1
and 1:1 rhizomatous:non-rhizomatous ratios, respectively, indicating
that rhizome presence in L. corniculatus germplasms G31276 and
G31317 is controlled by single dominant genes. The gene symbol
R is proposed for rhizome expression.
Effect of selection and temperature stress on the production
of 2n gametes in Lotus tenuis. Negri, V.; Lemmi, G.
Plant Breeding. 1998. 1174:345-349.
Five Lotus tenuis genotypes showing 2n pollen production
greater than 5% and producing 4x progenies in 4x (male sterile
Lotus corniculatus) x 2x crosses were found in different
natural populations. Meiotic analyses of these plants showed some
second metaphases with disoriented spindles, i.e. parallel and
tripolar spindles which resulted in diads and triads, respectively.
Because useful genes for winter growth and resistance to powdery
mildew from L. tenuis can be introgressed into L. corniculatus
via 2n gametes, a programme of selection was started to increase
the occurrence of 2n gamete production in L. tenuis. Controlled
crosses were performed between genotypes producing 2n gametes
and the progenies were checked for 2n pollen production and meiotic
aberration, following the same methodologies as used for the parental
plants. Although in some progeny plants the frequency of 2n gamete
production increased remarkably, the overall progeny level of
2n gamete production remained unchanged. This suggested that different
genes for meiotic aberration exist in natural populations and/or
differential seed-setting ability exists between genotypes. Diallel
crosses between selected genotypes confirmed this hypothesis.
Evaluation of 2n pollen production of clones grown under different
temperature regimes (warm vs. temperate) showed that, in L.
tenuis, the effects of genotype, temperature and genotype
x temperature interaction are significant. In particular, high
temperature increases the level of 2n gamete production in L.
tenuis.
Establishment and fecundity of Ostertagia circumcincta and
Trichostrongylus colubriformis in lambs fed lotus (Lotus
pedunculatus) or perennial ryegrass (Lolium perenne).
Niezen, J. H.; Waghorn, G. C.; Charleston, W. A. G. Veterinary
Parasitology. 1998. 78:13-21.
Forty-four 12- to 14-week-old Polled Dorset ram lambs, raised
helminth free from birth, were used to investigate the effects
of condensed tannins (CT) in lotus (Lotus pedunculatus
(L. uliginosus)) on lamb growth and gastrointestinal nematode
establishment and fecundity. CT bind to proteins in the rumen
and increase the flow of protein to the intestines. Lambs were
allocated to either a ryegrass (Lolium perenne) or lotus
diet fed ad libitum, with or without twice daily drenching of
polyethylene glycol (PEG) which binds with and deactivates the
CT. One week after allocation to the diets, each lamb was infected
per os with 10 000 Ostertagia circumcincta (Teladorsagia
circumcincta) and 10 000 Trichostrongylus colubriformis
larvae and slaughtered at 28 or 29 days pi. Lambs fed lotus had
lower faecal egg counts (P<0.0001) and lower O. circumcincta
burdens (P<0.001), fewer female O. circumcincta (P<0.001)
and higher faecal dry matter (P<0.001) than lambs fed ryegrass,
but numbers of T. colubriformis nematodes were not affected.
This trial did not ascribe beneficial effects of L. pedunculatus
to CT per se and the use of PEG does not seem appropriate to studies
of parasitology.
Structure and function of putative heterotrimeric G proteins
in higher plants. Iwasaki, Y.; Ishikawa, A.; Kato, T.; Nanbu,
N.; Asahi, T. Recent Research Developments in Agricultural &
Biological Chemistry. 1997. 1:59-70.
Putative heterotrimeric G proteins have been detected in Arabidopsis
thaliana, tomatoes, rice, Lotus japonicus and soyabeans.
These proteins may be involved in signal transduction.
Phenylalanine ammonia lyase and syringaldazine oxidase activities
in relation to lignin deposition in legumes. Bidlack, J. E.;
Buxton, D. R.; Shibles, R. M.; Anderson, I. C. Recent Research
Developments in Agronomy. 1997. 1:1-8.
Activities of phenylalanine ammonia-lyase (PAL) and syringaldazine
oxidase (SO) in maturing stems of Medicago sativa, Lotus corniculatus
and Trifolium pratense were determined at biweekly
intervals in a greenhouse experiment. Cell wall and lignin content
increased sigmoidally; PAL activity increased, peaked and decreased;
and SO activity increased, peaked and levelled off or decreased
as a function of regrowth days. Maximum deposition of lignin followed
that of other cell wall components. Time of maximum PAL activity
occurred 8 days before maximum lignin deposition in L. corniculatus
and T. pratense and 3 days after maximum lignin deposition
in M. sativa. Time of maximum PAL activity always preceded
time of maximum SO activity. SO activity was correlated with lignin
content in each species.
Establishment of species in simple and complex mixtures in
a permanent grassland of Festuca rubra-Agrostis tenuis
using the herbicide glyphosate.<Original> Instalarea
unor specii, amestecuri simple si complexe, pe o pajiste de Festuca
rubra-Agrostis tenuis, erbicidata cu "gliyfosate".
Rotar, I.; Rusu, M.; Prica, F. Notulae Botanicae, Horti Agrobotanici,
Cluj-Napoca. 1996/1997. 26/27:99-107.
A sward on Mount Cindrel, Romania dominated by F. rubra and
A. tenuis (A. capillaris) was treated with glyphosate
to reduce the content of Nardus stricta and other weeds
in autumn 1993 and direct sown with a mixture of Phleum pratense,
Trifolium repens, Festuca rubra, Dactylis glomerata and
Lotus corniculatus. Establishment and botanical composition
were monitored for a further 3 years. Using this treatment, N.
stricta and the weeds were largely replaced by P. pratense
and F. rubra.
Effect of sowing depth and soil water content on germination,
development and initial growth of Lotus spp. on clay soils.<Original>
Efecto de la profundidad de siembra y el contenido de agua del
suelo en la germinacion, desarrollo y crecimiento inicial de Lotus
spp., en suelos arcillosos. Acuna:, H.; Figueroa R., M.; Fuente
A., A. de la Agro-Ciencia. 1997. 13:265-274.
In experiments in 1995/96 in Chillan, Chile, in pots under a shelter,
L. corniculatus cv. Quimey, L. tenuis cv. Toba and
L. uliginosus were sown at depths of 0. 0.5 or 1.0 cm with
soil water at field capacity, 50% of usable soil water, or saturated
or flooded soil. Germination percentage was greater in L. corniculatus
than the other species regardless of conditions. Seed germination
and seedling growth and development were 20% higher with sowing
depths of 0.5 or 1.0 cm than with surface sowing. When temperatures
were low (daily mean <10 deg C), saturated or flooded soil
increased germination but had a negative effect on seedling development.
When temperatures were higher (daily mean 20 deg C), these conditions
had negative effects on germination and seedling development.
Characterization of sites where six native and naturalized
pasture species occur in the Dominio Humedo of Chile.<Original>
Caracterizacion de sitios de crecimiento de seis especies pratenses
nativas y naturalizadas del Dominio Humedo de Chile. Lopez C.,
I.; Balocchi L., O.; Lailhacar M.,:; Oyarzun S., C. Agro Sur.
1997. 25:62-80.
On the basis of sampling in spring and summer at sites dominated
by each of Bromus valdivianus, Agrostis capillaris, Lotus uliginosus,
Holcus lanatus, Anthoxanthum odoratum and Paspalum dasypleurus
(P. dasypleurum) in the Dominio Humedo, a coastal fringe
in central southern Chile, the differing site conditions (slope,
soil chemistry and physical properties) required by each species
are described.
Effect of two methods of sowing Lotus tenuis on its
establishment and forage production in grasslands in the flooding
pampa of Argentina.<Original> Efecto de dos metodos
de intersiembra de Lotus tenuis sobre su implantacion y
sobre la produccion de forraje de pastizales del area ganadera
del salado (Argentina). Colabelli, M.; Viviani Rossi, E. M. Avances
en Produccion Animal. 1997. 22:123-128.
In a field trial in 1991-93 in the Buenos Aires region, L.
tenuis was sown into grassland using a disc harrow with a
seed drill attached or using a rotary seed drill. Plant establishment,
plant density and dry matter production did not differ between
sowing methods. However, dry matter production was 20-26% higher
than in controls without oversowing of L. tenuis.
Genetic manipulation of condensed tannins in higher plants:
II. Analysis of birdsfoot trefoil plants harboring antisense dihydroflavonol
reductase constructs. Robbins, M.P.; Bavage, A.D.; Strudwicke,
C.; Morris, P. Plant physiology. 1998. 116:1133-1144.
We have produced and analyzed transgenic birdsfoot trefoil (Lotus
corniculatus L.) plants harboring antisense dihydroflavonol
reductase (AS-DFR) sequences. In initial experiments the effect
of introducing three different antisense Antirrhinum majus
L. DFR constructs into a single recipient genotype (S50) was assessed.
There were no obvious effects on plant biomass, but levels of
condensed tannins showed a statistical reduction in leaf, stem,
and root tissues of some of the antisense lines. Transformation
events were also found, which resulted in increased levels of
condensed tannins. In subsequent experiments a detailed study
of AS-DFR phenotypes was carried out in genotype S33 using pMAJ2
(an antisense construct comprising the 5' half of the A. majus
cDNA). In this case, reduced tannin levels were found in leaf
and stem tissues and in juvenile shoot tissues. Analysis of soluble
flavonoids and isoflavonoids in tannin down-regulated shoot tissues
indicated few obvious default products. When two S33 AS-DFR lines
were outcrossed, there was an under representation of transgene
sequences in progeny plants and no examples of inheritance of
an antisense phenotype were observed. To our knowledge, this is
the first report of the genetic manipulation of condensed tannin
biosynthesis in higher plants.
Symbiotic mutants deficient in nodule establishment identified after T-DNA transformation of Lotus japonicus. Schauser, L; Handberg, K.; Sandal, N.; Stiller, J.; Thykjaer, T.; Pajuelo, E.; Nielsen, A.; Stougaard, J. Molecular & general genetics: 1998. 259:414-423.
Identification of Rhizobium loti by immunodiffusion.<Original>
Identificacion de Rhizobium loti por inmunodifusion. Andreoli,
Y. E.; Escuder, A. M. Q. de; Laich, F. S.; Gonzalez, N. S. Ciencia
del Suelo. 1998. 16:16-19.
Percentage nodule occupation in Lotus tenuis and the competitive
ability of Rhizobium loti strain 733 against native rhizobial
populations in the soil are determined from field trial data.
A randomized complete block design with twelve repetitions, with
and without inoculation was used. Lotus seeds were inoculated
with the selected strain 733. Samples were taken in autumn and
spring: two samples in Balcarce and three in Maipu and Ayacucho.
In the initial samples all the nodules from each plot were pooled
for processing, however, for subsequent samples 10nodules were
selected at random from each plot to obtain pure cultures. Rhizobial
samples were analysed by immunodiffusion using antiserum 733.
Serologic relationship reactions were classified as: total identity,
partial identity and lack of identity. In Balcarce and Maipu no
naturalized rhizobia were detected before sowing and the recovery
of strain 733 after 18 months from inoculation was 78% and 69%
respectively. In Ayacucho, with naturalized population of 5.7
x102 rhizobia g-1 of soil, the recovery was only 13%.
Nodule parenchyma specific expression of the Sesbania rostrata
early nodulin gene SrEnod2 is mediated by its 3' untranslated
region. Chen Ru Jin; Silver, D. L.; Bruijn, F. J. de Plant
Cell 1040 4651 1998 10 p.1585 1602.
The early nodulin Enod2 gene encodes a putative hydroxyproline
rich cell wall protein and is expressed exclusively in the nodule
parenchyma cell layer. The latter finding suggests that the Enod2
protein may contribute to the special morphological features of
the nodule parenchyma and to the creation of an oxygen diffusion
barrier. TheEnod2 gene of the stem nodulating legume Sesbania
rostrata (SrEnod2) is induced specifically in roots by the
plant hormone cytokinin, and this induction occurs at a post transcriptional
level. In this paper, cis determinant(s) in the SrEnod2 locus
responsible for nodule parenchyma specific expression are characterized,
and it is shown that the 3' untranslated region (UTR) of the SrEnod2
gene is both required and sufficient for directing chimaeric reporter
gene expression in the nodule parenchyma of transgenic Lotus
corniculatus plants. Moreover, evidence is presented indicating
that the SrEnod2 3' UTR does not act as a tissue specific enhancer
element. By conducting a detailed deletion analysis of the 5'
and 3' SrEnod2 regions, the minimal promoter of the SrEnod2 gene
was delimited; the data suggested that the5' flanking sequences
are not essential for nodule parenchyma specific expression. This
finding is in contrast with the report that the 5'upstream region
of the soyabean Enod2 gene directs nodule parenchyma specific
expression, indicating that different mechanisms may be involved
in regulating the expression of these two genes. It is definitively
demonstrated that the cis element(s) for tissue specific expression
are located within the 3' UTR of a plant nuclear gene.
Symbiotic mutants deficient in nodule establishment identified
after T DNA transformation of Lotus japonicus. Schauser,
L.; Handberg, K.; Sandal, N.; Stiller, J.; Thykjaer, T.;Pajuelo,
E.; Nielsen, A.; Stougaard, J. Molecular and General Genetics
1998. 259:414 423.
Nitrogen fixing root nodules develop on legumes as a result of
an interaction between host plants and soil bacteria collectively
referred to as rhizobia. The organogenic process resulting in
nodule development is triggered by the bacterial microsymbiont,
but genetically controlled by the host plant genome. Using T DNA
insertion as a tool to identify novel plant genes that regulate
nodule ontogeny, two putatively tagged symbiotic loci, Ljsym8
and Ljsym13, were identified in the diploid legume Lotus japonicus.
The sym8 mutants are arrested during infection by the bacteria
early in the developmental process. The sym13 mutants are arrested
in the final stages of infection, and ineffective nodules are
formed. These two plant mutant lines were identified in progeny
from 1112 primary transformants obtained after Agrobacterium
tumefaciens T DNA mediated transformation of L. japonicus
and subsequent screening for defects in the symbiosis with Mesorhizobium
loti. Additional non tagged mutants arrested at different
developmental stages were also identified, and genetic complementation
tests assigned all the mutations to 16 monogenic symbiotic loci
segregating recessive mutant alleles. In the screen reported here
independent symbiotic loci thus appeared with a frequency of approx
equal to 1.5%, suggesting that a relatively large set of genes
is required for the symbiotic interaction.
The behaviour of some bird's foot trefoil (Lotus corniculatus
L.) lines and varieties under conditions of the Suceava Plateau.<Original>
Comportarea unor soiuri si linii de ghizdei (Lotus corniculatus
L.) in conditiile podisului sucevei. Popovici, D.; Dragomir,
N.; Ciubotariu, C.; Tonigar, D. S.C.A. Cercetari Agronomice in
Moldova. 1996. 29:117 122.
In field trials in 1992 95 on the Suceava Plateau, Romania, 7
birdsfoot trefoil (L. corniculatus) lines created at the
Timisoara Research Station were compared. Yields of up to 10.49
t dry matter/ha were obtained with cutting at flowering and 8.90
t with cutting at bud formation. Line TM 18 showed high persistence
when cut at flowering.
Strategy for catch crop development. II. Screening of species
undersown in spring barley (Hordeum vulgare L.) with respect
to catch crop growth and grain yield. Karlsson Strese, E.
M.; Rydberg, I.; Becker, H. C.; Umaerus, M. Acta Agriculturae
Scandinavica. Section B, Soil and Plant Science. 1998. 48:26
33.
Catch crops are recommended in Sweden as a way of decreasing nitrogen
leaching from arable land. In six field trials a total of 118accessions
from 39 species of Poaceae, Fabaceae and "other" families
was tested as potential undersown catch crops. Barley yield was
used as an indicator of competition. Establishment, height and
green matter production, after harvest of the main crop and in
December, were estimated for the accessions. In general, the Poaceae
showed the highest green matter production, but they also had
the largest negative influence on barley yield. With Poaceae as
a catch crop, the barley yield was reduced by 5 15% for all species
except for Agrostis tenuis, Festuca rubra and Holcus
lanatus, but these three species had a lower green matter
production than the average of all Poaceae. Of all Poaceae investigated,
only one accession of Dactylis glomerata combined high
green matter production with no negative influence on barley yield.
In the Fabaceae and the "other" families, 11 out of
27 species had no negative influence on barley yield and of these
Trifolium repens, Lotus corniculatus and Cichorium intybus
had above average green matter production.
Screening pasture species for shade tolerance. Devkota,
N. R.; Kemp, P. D.; Hodgson, J. Proceedings Annual Conference
Agronomy Society of New Zealand. 1997. 27:119 128.
In a field trial in 1996 in Palmerston North, New Zealand, Dactylis
glomerata cv. Grasslands Wana, Lolium perenne cv. Grasslands
Nui, Holcus lanatus cv. Massey Basyn, Plantago lanceolata
cv. Grasslands Lancelot, Festuca arundinacea cv. Grasslands
Advance, Agrostis capillaris cv. Grasslands Muster, Poa
trivialis cv. Sabre, Trifolium repens cv. Grasslands
Tahora, T. subterraneum cv. Karridale and Lotus uliginosus
cv. Grasslands Maku grown in pots were shaded so that they received
14, 18, 27, 43 or 73% of the ambient photosynthetically active
radiation (PAR). Tillering of all species decreased with increasing
shade. However, mean tiller numbers per plant at the final cut
under the lowest PAR were significantly higher for H. lanatus
and D. glomerata than for the other grass species.
L. uliginosus produced a higher number of branches under
14% ambient PAR than the other legumes.
Transpiration rates and canopy conductance of Pinus radiata
growing with different pasture understories in agroforestry systems.
Miller, B. J.; Clinton, P. W.; Buchan, G. D.; Robson, A. B.
<Editors> Dye, P. J. Tree Physiology. 1998 18 :575 582.
Forests at the limit: environmental constraints on forest function.
A selection of papers presented at an international symposium
held at Skukuza, Kruger National Park, South Africa, 11 17 May,
1997. Tree transpiration and canopy conductance were measured
in Pinus radiata at two low rainfall sites of differing
soil fertility in Canterbury, New Zealand. At the more fertile
Lincoln site, the effects of two common pasture grasses (Dactylis
glomerata and Lolium perenne)on tree transpiration
and canopy conductance were also studied. At the less fertile
Eyrewell Forest site, the effect of no understorey, and the effects
of irrigation in combination with mixtures of grass(Agrostis
capillaris and Holcus lanatus) or legume (Lotus
pedunculatus (L. uliginosus)) species were determined.
Tree xylem sap flux (Fd') was measured by the heat pulse method.
Total canopy conductance to diffusion of water vapour (Gt) was
calculated by inverting a simplified Penman Monteith model. The
different treatment effects were modelled by the simple decaying
exponential relationship Gt = Gtmax( bD), where D= air saturation
deficit. At the Lincoln site, trees with an understorey of D.
glomerata had lower Fd' and Gtmax than trees with an understory
of L. perenne, although the sensitivity of Gt to increasing
D (i.e., the value of b) did not differ between treatments. At
the Eyrewell site, irrigation only increased Fd' in the absence
of an understorey, whereas the presence of understorey vegetation,
or lack of irrigation, or both, significantly reduced Gtmax and
increased b. It is concluded that the selection of understorey
species is critical in designing successful agroforestry systems
for low rainfall areas.
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