Non-parametric analysis of phenotypic stability in chickpea (Cicer arietinum L.) genotypes in Iran

The objective of this study was to compare non-parametric stability procedures, and to apply different non-parametric tests for genotype × environment interaction (G×E) on seed yield data of 17 chickpea genotypes grown during 2004-05 growing seasons in 10 rainfed environments in Iran. The non-parametric measures used for G × E interaction were highly significant (P < 0.01), suggesting differential responses of chickpea genotypes to the test environments. Spearman’s rank correlation was used to measure the relationship between the stability statistics. To understand better relationships among the non-parametric methods, principal component analysis was performed. The results of this analysis and correlation analysis of non-parametric stability statistics and grain yield indicated that only seed yield-stability statistic (Ysi) would be useful for simultaneous selection for high grain yield and stability. According to Ysi statistic, genotype no. 13 was identified as the most stable genotype. It was observed that this non-parametric statistics were associated with high seed yield. Si(1), Si(2), Si(3) and NPi(1) were positively correlated to mean seed yield, however, Si(6), NPi(2), NPi(3) and NPi(4) were negatively correlated to mean seed yield.