Co-Heritability of Yield Related Traits in Soybean (Glycine Max L.) Across Planting Environments

Abstract

Experiments were carried out to estimate genetic variability and co-heritability for yield contributing traits in soybean under normal (June planting) and late (July planting) environments. Eighteen soybean genotypes were evaluated in randomized complete block design with three replications as independent experiment under each environment during kharif crop season 2015 at The University of Agriculture, Peshawar. Analysis of variance across environments revealed significant differences among two environments for all traits except pod length, seeds pod-1 and harvest index. Genetic variation among soybean genotypes was also highly significant for all the traits. G × E interaction was significant for all the traits except seeds pod-1. Means for days to total pods plant-1 (26.90 vs. 21.76), seeds pod-1 (3.88 vs. 3.08), seeds plant-1 (154.64 vs. 62.86), 100-seed weight (9.01 vs. 7.43 g), biological yield (5753.00 vs. 655.50 kg ha-1) and seed yield (1021.00 vs. 162.79 kg ha-1) under normal and late environment, respectively. Genotypes E-1469 and E-1360 were high yielding under normal and late plantings, respectively. Co-heritability estimates for seed yield and pod length were 0.99 under normal, and 0.97 under late planting. For seed yield vs. total pods plant-1 co-inheritances were 0.92 under normal and 0.83 under late planting.  Likewise for pair of seed yield vs. 100-seed weight co-heritability were 0.99 under normal and 0.97 under late planting, Furthermore co-heritability for  seed yield vs. biological yield was 0.99 under both normal and late environment. It is found that soybean genotypes produced high yield, and showed high co-heritability for yield contributing traits under normal than late planting experiment. This high co-heritability of seed yield with pod length, total pods plant-1 and 100-seed weight under normal planting as compared to late planting, indicating genetic improvement from the joint selection of these traits in future breeding programs and these traits could be recommended as a better index to rise yield under normal (June) planting of soybean.