(588)-(600) Proposition de rejet des noms Aegilops ovata L., Bromus hordeaceus L., Carex muricata L., Crataegus × media Bechst., Crataegus oxyacantha L., Dipsacus fullonum L., Euphorbia verrucosa L., Medicago polymorpha L., Phleum exaratum Hochst. ex Griseb., Potamogeton pusillus L., Salix × smithiana Wild., Spergularia media (L.) C. Presl (≡Arenaria media L.) et Vulpia membranacea (L.) Dum. (≡Stipa membranacea L.)

Taxon ◽  
1981 ◽  
Vol 30 (1) ◽  
pp. 361 ◽  
Author(s):  
Jacques Lambinon
1988 ◽  
Vol 28 (6) ◽  
pp. 765 ◽  
Author(s):  
MDA Bolland ◽  
MJ Baker

Seed of 2 cultivars of wheat (Triticum aestivum) and 1 burr medic (Medicago polymorpha) with increasing phosphorus (P) concentrations (wheat 1.4-3.7 g P/kg dry matter, medic 3.3-7.9 g P/kg dry matter) were collected from field experiments with variable levels of applied superphosphate (wheat 0- 577 kg P/ha, medic 0-364 kg P/ha) in south-western Australia. These seeds were used in further experiments to examine the effect of seed P concentration on the subsequent dry matter (DM) production of seedlings and plants in 3 glasshouse pot experiments and 1 field experiment. Seed of the same size (wheat, 35 mg/seed; medic, 3.6 mg/seed) but with increasing P concentration produced substantially higher DM yields in the absence or presence of freshly applied superphosphate P up to 28-35 days after sowing in the pot experiments and 67 days after sowing in the field experiment.


1996 ◽  
Vol 126 (2) ◽  
pp. 161-168 ◽  
Author(s):  
C. Porqueddu ◽  
A. Loi ◽  
P. S. Cocks

SUMMARYThe hardseededness and pattern of hard seed breakdown of 35 accessions of Medicago polymorpha, collected in Sardinia, were compared with Circle Valley, an Australian cultivar, near Sassari, northern Sardinia. The seed was produced in three consecutive years (1991–93), and the hardseededness measured at intervals in trie field during the summer following its production. The results were related to previously measured pod characteristics that separated the varieties polymorpha and vulgarisThe variety polymorpha, which had been collected mainly from coastal regions, was harder seeded than the variety vulgaris, which had been collected mainly from cooler, inland regions. Wherever the origin, hardseededness levels remained > 85% even in the year when seed softening was greatest (1992). In other years means of 94% (1991) and 97% (1993) of seed remained hard in late September. In 1992 and 1993 most hard seed breakdown occurred between early August and early September, while in 1991 hard seed breakdown occurred in September itself. There was little difference between varieties in the pattern of hard seed breakdown. Seedling emergence was related to the amount of seed that became soft during the previous summer. The results also confirmed that hard seeds soften sequentially from the proximal end of the pod (nearest the calyx) to the distal end.The Australian cultivar was one of the hardest seeded accessions, showing very little hard seed breakdown during the experimental period. This result highlights the importance of selecting pasture legumes under the conditions in which they are to be used: in Australia, cultivar Circle Valley usually loses some 20% of its hardseededness in the first year, comparable with the softest Sardinian accessions in Sardinia. Even among the Sardinian accessions, most were probably too hard seeded in 1993. Nevertheless it is likely that material in this experiment will be released as commercial cultivars for Sardinia and other similar environments in the Mediterranean basin.


2016 ◽  
Vol 64 (1) ◽  
pp. 65 ◽  
Author(s):  
Heidi A. Waddell ◽  
Richard J. Simpson ◽  
Hans Lambers ◽  
Brent Henderson ◽  
Megan H. Ryan ◽  
...  

Rytidosperma species are perennial grasses found in cool temperate grasslands of Australia. The species differ in their intrinsic growth rates, response to phosphorus (P) fertiliser application and critical external P requirements (P required for 90% maximum growth). The present study examined whether internal P-utilisation efficiency (PUE) by Rytidosperma species influenced these differences. The PUE of nine Rytidosperma species and two grasses of Mediterranean origin, Bromus hordeaceus L. and Lolium perenne L., was assessed using alternative measures of shoot P concentration or its reciprocal. No measure of PUE was correlated with the critical external P requirements of the species. One measure of PUE, shoot dry matter per unit P, when assessed at a common shoot P content was correlated with potential growth rate (P < 0.001; r = 0.93; 4 mg shoot P). However, other measures of PUE were not correlated with potential growth rates. All of the fast-growing species (B. hordeaceus, L. perenne, Rytidosperma duttonianum (Cashmore) Connor & Edgar and Rytidosperma richardsonii (Cashmore) Connor & Edgar) exhibited high PUE, whereas PUE varied substantially among the slower-growing species. The fast-growing Rytidosperma species differed in the contribution that area-based P concentration of leaves and specific leaf area (SLA) made to the achievement of high PUE, and they retained shoot-morphology traits normally associated with slow-growing species such as smaller leaf area, smaller SLA and higher leaf dry matter content.


1971 ◽  
Vol 22 (2) ◽  
pp. 215 ◽  
Author(s):  
RD Brock ◽  
WD Andrew ◽  
R Kirchner ◽  
EJ Crawford

Treatment of dry seeds of Medicago polymorpha L. var. polynzovpha with 20 krad gamma rays resulted in a large increase in variation for flowering time. Selection among spaced plants in the M2 and M3 generations, primarily for early flowering and secondarily for plant vigour and fertility, resulted in the isolation of mutant lines which flowered from 2 to 3 weeks earlier than the unirradiated controls and which were comparable in vigour with the unirradiated controls. This method of generating variability for plant improvement programmes proved to be simple, relatively quick, and economical (c. 1000 plants x 4 generations). It is recommended for more extensive use with self-fertilizing annual species where the primary selection criteria are clear cut and simply measured.


Author(s):  
Zoie C. Lopez ◽  
Maren L. Friesen ◽  
Eric Von Wettberg ◽  
Leslie New ◽  
Stephanie Porter

1995 ◽  
Vol 124 (3) ◽  
pp. 419-426 ◽  
Author(s):  
A. Loi ◽  
C. Porqueddu ◽  
F. Veronesi ◽  
P. S. Cocks

SUMMARYThirty-five populations of Medicago polymorpha were collected from throughout Sardinia (Italy) in 1989 with a view to developing pasture species suitable for improving degraded grasslands in the northern Mediterranean basin. Herbage and seed production were compared with the Australian cultivar, Circle Valley, over 2 years at Bonassai, north Sardinia. Regeneration in the 2 years after sowing and seed size were also estimated. All variables were related to collection site parameters using multivariate analysis.Herbage production varied between 2 and 8 t dry matter/ha, and up to 1·5 t/ha of seed was produced. K-means clustering of agronomic and morphological variables indicated that there were two groups present; one similar to variety polymorpha and one to variety vulgaris. There were two other single entry clusters, one of which contained cv. Circle Valley. Principal component analysis of the environmental variables indicated that cluster 1 (vulgaris) was more likely to come from mountainous areas where winter temperatures are low, and cluster 2 (polymorpha) from coastal areas where temperatures are mild. Regeneration of cluster 1 was better than that of cluster 2, which in turn was better than Circle Valley, indicating that populations in cluster 1 are better adapted to the management system imposed at Bonassai.The results indicate that M. polymorpha has considerable potential to improve the grasslands of Sardinia. However, it is unlikely that imported cultivars will be successful, and it seems important that the selection of local populations should continue. Commercial seed production in Sardinia is likely to be a problem, and grazing management under the conditions of communal ownership may have to be reviewed. It is important that future research and development involves farmers and other industry groups.


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