Evaluation of soybean genotypes using drought stress tolerant indices

Abstract This experiment was conducted on a research farm of Mahidasht in the west part of Iran in RCBD design with three replications under normal and drought stress conditions. The analysis of variances demonstrated high significant results between studied genotypes on evaluated traits under both conditions. The varieties including Union, Clark, Elgine, L17 and Hy-1 had the highest while Williams, Halcor, Hack and Flanklin had the least grain yield per hectar under normal condition. In drought stress condition, the varieties such as Clark, LD9 and Elgine had the highest while Steel, Halcor and Baj-maj had the least grain yield. The M9 had the highest number of grain and pods per plant. Similarly L17 had the highest amount of grain weight under normal condition while L17, M9 and Steel had the highest number of grain and pods per plant under drought stress. In this study 6 drought tolerant indices on 14 soybean genotypes, indentified L17 as the highest potential yield 0.590 kg/plot while Bajmaj and Hack as the lowest 0.326 and 0.313 kg/plot. On the other hand, Clark and L17 had the highest yield stability while Halcor and Baj-maj showed the lowest stability of yield. The highest amounts of STI, GMP, MP, HARM indices was obtained for L17 but Baj-maj showed the least amounts of STI, GMP and HARM. The evaluation of biplot on six studied indices and 14 soybean genotypes revealed that GMP and STI had positive correlation with both stress and non-stress yields. Considering three dimensional plot in genotypes scattering using STI, L17, Hy-1, Elgine, LD9 and Clark were in A region of plot. On the other hand, Halcor, Steel, Flanklin, Williams, Hack and Baj-maj were in D region of plot. It means they had low yield under stress and non-stress conditions.