Stability Analyses for Root Shoot Traits in Soybean (Glycine max L.) under Different Water Regimes

Abstract

Performance of genotypes is evaluated on the basis of the selection of preferred distinct agronomic traits, which are observed during experimentation. Soybean is an economically important oilseed crop sown across the world. It is cultivated in tropical, subtropical and temperate regions. The study aims to conduct Stability analyses for root shoot traits in soybean (Glycine max L.) under different water regimes. Sixty genotypes of soybean were assessed in a completely randomised block design for stability analysis under four different water regimes with two replications for each regime during 2022 under net house conditions. The genotypes were exposed to drought conditions by imposing different levels of water after the two-leaf stage of seedlings. Observations were recorded for ten traits, namely, root length, shoot length, root fresh weight, shoot fresh weight, root dry weight, shoot dry weight, root shoot ratio by weight, root shoot ratio by length and relative leaf water content. A significant level of deviation in expression of study traits was observed for genotypes, environments, genotype x environment interaction, environment + (genotype x environment) interaction, environment (linear) and genotype x environment (linear) interaction. In consideration of stability of genotypes in non-stress, water stress and overall environments it was observed that for root length, genotypes GW234, GW207, GW28 and AGS25; for shoot length genotype GW225; for root fresh weight genotype GW291; for shoot fresh weight genotype GW17; for relative leaf water content genotype SQL110; for root dry weight genotype GW225; for shoot dry weight genotype RSC1107;  for root shoot ratio by length genotype SQL110; for root shoot ratio by weight genotype RSC1107 showed higher mean value as compared to grand mean, regression coefficient around unity (bi = 1) and non-significant deviation from regression (S2di).  Thus, these genotypes were found to be stable for varying environmental conditions. In future, research should focus on genotypes GW234, GW207, GW28, AGS25, GW225, GW291, GW17, SQL110, and RSC1107 may be used directly or as a parent for the development of varieties under normal and water stress conditions, respectively, because these genotypes were identified for their superior and stable root-shoot traits.