بررسی شاخص های انتخاب در تعدادی از ژنوتیپ های برنج (Oryza sativa L.)

One of the most important purpose in breeding program is increasing grain yield per hectare. Using selection indices is the most effective methods of selection for simultaneous improvement of grain yield and related traits, which often have a quantitative inheritance. In this study, 29 rice genotypes (9 parents and 20 progenies) were evaluated. The numbers of filled grains in panicle and panicle fertility percentage traits have the highest Broad-sense heritability and highest positive and significant correlation with yield. The number of grain in panicle has the highest direct genotypic effect on grain yield. Analysis of regression showed that number of grain in panicle, panicle fertility percentage, number of filled grains in panicle and number of days to complete panicle have the highest affect on yield variation and therefore, using these 4 traits with grain yield, was considered as Selection indices. Results of selection indices showed that the phenotypic direct effect, genotypic correlation and Additive variance indices via optimum index and genotypic correlation, Broad-sense heritability and regression coefficient via Base index are the best indices of increasing yield trait. Selection for number of grain in panicle, panicle fertility percentage, number of filled grains in panicle and number of days to complete panicle by using Genotypic correlation coefficient as the economic weight would be effective selection criteria in each of the base or optimum method.