Medicago littoralis: Rhodes, L.

The tolerance of 5 species of annual medics (Medicago spp.), Trifolium subterraneum cv. Nungarin, and hedge mustard (Sisymbrium orientale) to a range of post-emergence broadleaf herbicides was tested over 2 years. The least damaging to M. truncatula was 2,4-DB, which provided more consistent and effective control of hedge mustard than the other chemicals tested, including the less expensive tank mix of 2,4-DB + diuron. MCPA amine or sodium salt (300 g a.i./ha), bromoxynil (420 g a.i./ha), and tank mixes containing MCPA amine (150-175 g a.i./ha) severely damaged annual medics, particularly M. truncatula, with flowering delayed by up to 21 days, and dry matter and seed yields often significantly (P<0.05) reduced. Seed yields of most test plants indicated a degree of recovery from herbicide damage assessed visually after 10 days. Hedge mustard was not always as severely damaged by MCPA amine as was M. truncatula. Nungarin subterranean clover and M. aculeata SAD 2356 were more tolerant than the M. truncatula cultivars of MCPA amine, MCPA sodium salt, MCPA tank mixes, and bromoxynil, and less tolerant of 2,4-DB. Medicago littoralis, M. polymorpha and M. laciniata were severely damaged by bromoxynil but were more tolerant of MCPA than M. truncatula.

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A cytogenetic and pollen study of annual Medicago species from Soummam Valley (Northeastern of Algeria)

Acta Botanica Croatica ◽

10.2478/botcro-2019-0010 ◽

2019 ◽

Vol 78 (1) ◽

pp. 82-90 ◽

Cited By ~ 1

Author(s):

Linda Djafri-Bouallag ◽

Malika Ourari ◽

Mohamed Sahnoune

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Cytogenetic Study ◽

Pollen Viability ◽

Pearson Correlation ◽

Pollen Grains ◽

Pollen Size ◽

Relative Standard ◽

Medicago Littoralis ◽

Annual Medicago

Abstract This paper reports a cytogenetic study of eight Medicago L. species sampled from the Soummam Valley (northeastern Algeria). Chromosome numbers and meiosis irregularities during microsporogenesis were explored. Pollen viability rate and pollen size were also examined. The studied taxa are diploid and display biva-lent pairing and regular chromosome segregation during meiosis. Although meiosis appears regular, some anomalies were detected in relatively high cumulated rates (14.66%–26.14%). The most common meiotic abnormality examined here is related to cytomixis (from 14.66% in M. littoralis to 25.83% in M. laciniata). Other anomalies were also detected, including chromatic bridges, asynchronous divisions, micronuclei and multipolar cells. Consequently, the species exhibited varying percentages of pollen viability (from 70.11% in M. laciniata to 99.14% in M. littoralis). Pollen viability was negatively correlated with meiotic abnormalities (Pearson correlation coefficient R = −0.72, p = 0.043). The pollen grains were also heterogeneous in size. Medicago truncatula Gaertn. and M. laciniata (L.) Miller presented the most variable pollen size (relative standard deviation exceeding 19%). Medicago littoralis is distinguished from other species by possessing homogeneous and large sized pollen (relative standard deviation RSD = 6.73 %). The cytogenetic and pollen data provided by this study are discussed in the context of species systematics and in the perspective of genetic improvement.

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Decomposition of plant material in Australian soils. II. Residual organic 14C and 15N from legume plant parts decomposing under field and laboratory conditions

Soil Research ◽

10.1071/sr9840331 ◽

1984 ◽

Vol 22 (3) ◽

pp. 331 ◽

Cited By ~ 45

Author(s):

M Amato ◽

RB Jackson ◽

JHA Butler ◽

JN Ladd

Keyword(s):

Plant Material ◽

Calcareous Soil ◽

Laboratory Studies ◽

Plant Parts ◽

Drying And Rewetting ◽

Legume Plant ◽

Medicago Littoralis ◽

Average Residual ◽

Medicago Species ◽

Field And Laboratory Conditions

14C- and 12N-labelled Medicago littoralis and Medicago truncatula plant parts, ground or unground, were added at a rate equivalent to 50 kg nitrogen ha-l to a calcareous soil in the field and allowed to decompose for two years. Both plant types behaved similarly but the various plant parts decomposed to different extents. After 4 weeks' and 2 years' decomposition respectively, the residual organic 14C in soil from leaves of both Medicago species accounted for about 62% and 20% of input, from stems 70% and 24% and from roots 80% and 32%. Average residual organic 15N accounted for 64% and 40% of leaf 15N, 87% and 56% of stem and 81% and 50% of root 15N. Grinding had no effect on the residual 14C and 15N of plant parts. After 2 years' decomposition the proportion of residual and 15N present as labelled biomass was greatest for leaf residues. Results from laboratory studies of 20 weeks' decomposition of ground and unground Medicago littoralis plant parts under continuously moist and intermittently dry and rewetting conditions were consistent with field results. Grinding significantly promoted pod decomposition under most incubation conditions. Drying and rewetting promoted decomposition of the plant parts. Pods were affected more than other parts. The longer the time moist following drying, the greater the decomposition. The more frequent the drying and wetting cycles, the greater the decomposition.

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Genetic analysis of tolerance to the root lesion nematode Pratylenchus neglectus in the legume Medicago littoralis

BMC Plant Biology ◽

10.1186/1471-2229-14-100 ◽

2014 ◽

Vol 14 (1) ◽

pp. 100 ◽

Cited By ~ 3

Author(s):

Klaus H Oldach ◽

David M Peck ◽

Ramakrishnan M Nair ◽

Maria Sokolova ◽

John Harris ◽

...

Keyword(s):

Genetic Analysis ◽

Root Lesion Nematode ◽

Pratylenchus Neglectus ◽

Medicago Littoralis ◽

Lesion Nematode

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Bioassay responses of ewes to legume swards. II. Uterine weight results from swards

Australian Journal of Agricultural Research ◽

10.1071/ar9670495 ◽

1967 ◽

Vol 18 (3) ◽

pp. 495 ◽

Cited By ~ 19

Author(s):

D Bennett ◽

FHW Morley ◽

A Axelsen

Keyword(s):

Trifolium Repens ◽

Trifolium Pratense ◽

Trifolium Subterraneum ◽

Uterine Weight ◽

Trifolium Incarnatum ◽

Variable Activity ◽

Chemical Assay ◽

Medicago Littoralis ◽

Reasonable Evidence ◽

Trifolium Repens L

Three years' results of sheep uterine weight bioassays on a range of clover swards are presented. Trifolium pratense L. (var. Grasslands Hamua Broad) and Trifolium subterraneum L. (var. Dinninup, Dwalganup, Tallarook, and Yarloop) showed high activity whenever they were green. Trifolium fragiferum L. (mixed+Palestine), Trifolium repens L. (var. Victorian Irrigation), and Trifolium subterraneum L. (var. Bacchus Marsh, Howard, Marrar, and a breeder's selection) showed variable activity; Medicago sativa L. (var. Hunter River), Medicago littoralis (Rhode), Trifolium alexandrinum L., Trifolium incarnatum L. (var. Dixie), and Trifolium repens L. (var. Grasslands Huia and Ladino) have not shown activity. Spraying two of the clovers with paraquat and dosing the sheep with cobalt sulphate had no effect on activity. There was a strong seasonal trend with highest activity in midwinter and lowest in mid spring. The relationships between chemical assay and bioassay results are discussed. There is reasonable evidence that the activity of Victorian Irrigation white clover is not related to any of the compounds being measured.

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