Evaluation of selection indices for improving grain yield in Cuminum cyminum L.

The selection indices is one of the most effective methods for improving complex traits such as yield. In the current study, 50 genotypes of cumin (Cuminum cyminum L.) were evaluated to assess the efficiency of different selection indices. The experiment was conducted in a randomized complete block design whit three replications in the Research Farm of Shahid Bahonar University, Kerman, Iran in 2011-2012. The Smith-Hazel and Pesek-Baker indices were evaluated based on seven traits including plant height, number of branches, number of umbels/plant, number of umbelets/plant, number of seeds/plant, seed yield/plant and shoot weight (with and without seed). The results of response to selection and relative selection efficiency indicated that the genotypes with higher number of seeds and branches/plant and lower plant height had the highest yield potential. In the Smith-Hazel index, number of branches and umbelets/plant had the highest response to selection, while in the Pesek-Baker index, the number of umbels/plant had the highest response to selection. Our results indicated that the Smith-Hazel index had the most selection efficiency and could be used in cumin breeding programs.