Characterization of Milk Vetch(Astragalus sinicus L.)Germplasm Seed with Morphology and Ecological Stoichiometry in Carbon,Nitrogen and Potassium

The seed metrology characteristics in different Milk vetch (MV) germplasm were evaluated with morphology and ecological stoichiometry methods and were used in classification for MV germplasm.Comparing the thousand grain weight among 11 Milk vetch varieties, the heaviest one was found in‘Maxi'with average 3.40 g and the lighter were ‘Guangze'and ‘Minzi 3'with 3.05 g and 3.11 g, respectively.The thousand grain weight indicated the‘Maxi'variety in yield but not for its early ripe character.The total surface area of seed among 11 varieties, the smallest one was‘Minzi 5'with 3.46mm2 and the biggest was‘Maxi'with 4.12mm2.The seed form was reniform and subreniform with the proportion for 83% ⁹6.7% of total seeds.The highest ratio of reniform seed was found in‘Minzi 7'with 96.7%, while it in‘Minzi 4'and‘Minzi 5'was similar as the lowest with 83%.The difference between the highest and the lowest ratios was significant.With correlation analysis, the data showed that the surface area of seed was correlated positively with thousand grain weight (r=0.698*) .The ratios in C/N and C/P were higher for early ripe varieties, such as‘Guangze', than for other varieties.Although the indexes in the thousand grain weight, surface area and morphology of MV seed could not be used in differentiation for the genotype of the varieties, the indexes might be referred in use for identifying of the varieties.Ratios in C/N and C/P could be used in identification for Milk vetch character in early or late ripe varieties.