وراثت پذيري عملكرد و صفات مورفولوژي در ژرم پلاسم يونجه هاي ايراني

Inheritance of yield and morphological traits in Iranian alfalfa germplasm

Twenty eight native alfalfa populations and two improved cultivars were used to estabilish a polycross nursery. Leaf number per seedling, length of longest stem, cotyledon length and width, unifoliate internode length, and leaf blade length and width were measured on over 2000 individual 30-days old seedlings. The seedlings were transplanted to the field, and individual plant’s fresh and dry weight (IPFW, IPDW), number of shoots per plant (NS) and plant height (PH) were measured on 900 plants in four harvests. Days until 50% flowering, percentage of ground cover, fresh and dry weight of leaves / plant ratio, and size of trifoliate leaves were also measured in experimental plots. Narrow sense heritability values based on individual plant measurment(H1) and on plot mean basis(H2) were calculated. For each trait, H1 was usually lower than the corresponding values of H2, and these differences were more obvious for mature plant heritabilities. The heritability values for the seedling traits were higher than mature plant traits. Among mature plant traits PH and NS had the highest and lowest heritability values, respectively. Among seedlig traits the highest heritability belonged to cotyledon length.