Genotype × Environment Interaction and Stability Analysis of Seed Yield of Durum Wheat Genotypes in Dryland Conditions

Abstract

The objective of this investigation was to evaluate seed yield of twenty durum wheat (Triticum turgidum spp. durum) genotypes. Evaluation of genotype × environment interaction and stability were also carried out at five diverse locations during the 2007-2009 growing seasons. Significant differences were found among the genotypes for seed yield on individual years and combined over years, in all locations. Genotype × environment interaction showed significance (p>0.001) for seed yield. According to the coefficients of linear regression and deviations from the regression model, genotypes G2, G7 and G8 proved to be the most stable while based on α and λ parameters, genotypes G7, G12 and G13 were identified the most stable. Clustering genotypes based on all stability methods and mean yield divided them into four major classes, which Class II had relatively high stability and high mean yield performance. To compare relationships among stability statistics, hierarchical clustering procedure showed that the ten stability statistics and mean yield could be categorized into three major groups, which methods of Group C indicated dynamic concept of yield stability. The genotypic stability, stability variance, superiority index and desirability index provide information for reaching definitive conclusions. Also, the best recommended genotypes, according to the present investigation, were G2 (2697.18 kg ha-1), G7 (2644.70 kg ha-1), G8 (2580.16 kg ha-1) and G10 (2637.43 kg ha-1), which had high mean yield and were the most stable genotypes based on the above mentioned stability statistics.