Selection Indices fo Seed Yield Improvement in Sesame (Sesamum indicum L.)

Seed yield of the crops is a quantitatively inheritated trait and much affected by environemtal conditions; therefore, selection for genetic improvement of seed yield may have low efficiency because of the environment effectes. Selection indices can be more effective for simultaneous improvement of seed yield components and finally the seed yield. In order to investigate selection indices for seed yield improvement in sesame, 15 breeding lines along with five local populations of this crop were evaluated in a randomized complete block design with three replications at the research farm of Isfahan University of Technology in 2009. In this study, the traits of capsules/plant, seed weight, seeds/capsule, seed yield/plant and seed yield/plot were evaluated. The Smith-Hazel 1, Smith-Hazel 2 and Pesek-Baker indices were identified based on seed yield components of capsules/plant, seeds/capsule and seed weight. The results showed that seed yield was highly correlated with each of these indices and the estimated efficiency of indirect selection via these indices was relatively high. Thus, it seems that these selection indices can be effectively used for seed yield improvement. The estimated selection efficiency for improvement of seed yield/plot via selection for Pesek-Baker index was slightly more than that of Smith-Hazel ones. However, the efficiency of the Smith-Hazel indices for simultaneous improvement of capsules/plant, seeds/capsule and seed weight was a little higher than that of Pesek-Baker inde