نحوه كنترل ژنتيكي عملكرد و ميزان روغن دانه در گلرنگ هاي بومي با استفاده از تجزيه ميانگين نسل ها

Genetic mode controlling seed yield and oil content in local Safflower genotypes using generations mean analysis

Information on genetic control of agronomic characteristics, inbreeding depression and heterosis effects is needed to improve efficiency of breeding programs. Safflower genotype lines selected from different local populations along with their F, and F2 generations were evaluated in this study. Results of generations mean analysis showed that additive and dominance effects play a major role in control of seed yield per plant. Considering the dominance parameter in genetic model, it was concluded that in some crosses responsible alleles for increasing yield per plant were dominant and in other tosses were recessive. Heterosis relative to high parent for seed yield per plant varied from 2.8 to 121.0% in different crosses. Also, one generation of inbreeding decreased (maximum to 18.9%) and increased (maximum to 19.5%) seed yield per plant in defferent crosses. The additive-doinance genetic model explained most of variation among generations for oil content in most crosses, especially IUTKH211*xIUTE1449 and IUTH13*IUTE1449. Therefore, selection could improve oil content in variation from -12.6 to 14.9%. Inbreeding decreased (maximum to 7.5%) and increased (maximum to 17.7%) oil content in different crosses. The additive dominance genetic model failed to explain observed variation for days to 50% flowering, 100-seed weight and plant height in most of crosses. This was an indication that epistatic effects might play a considerable role in controlling these traits. Maximum amount of heterosis relative to hight parent for 100-seed weight, days to flowering and plant height were 14.8, 1.9 and 3.1%, respectively. However, inbreeding had no considerable effects on these traits.