Analysis of Genotype x Environment Interactions for Grain Yield in Durum Wheat
Genotype x environment (GE) interactions are important sources of variation in crop breeding programs. The objectives of this study were (i) to analyze GE interactions on grain yield of one bread wheat (Triticum aestivum L.) and 19 durum wheat [T turgidum L. subsp. durum (Desf.) Husn.] genotypes by the additive main effects and multiplicative interaction (AMMI) model, and (ii) to evaluate genotype (G), environment (E), and GE interactions with the statistical parameters of AMMI statistic coefficient (D), AMMI stability value (ASV), regression coefficient (b) and ecovalence (W-2). Main effects due to E, G, and GE interaction as well as first three interaction principal component axes (IPCA 1 to 3) were found to be significant (P < 0.01). The AMMI biplots distinguished genotypes with wide and specific adaptation and environments with high and low genotype discrimination ability. Ranking the statistical parameters indicated that they are similar in general, especially for the genotypes with similar responses and also for the environments with similar discrimination ability. The results show that the statistical parameters as well as the AMMI model are useful for analyzing GE interaction. Based on the AMMI model, the recommended genotypes had more grain yield improvement in favorable than unfavorable environments. The genotypes selected based on stability of grain yield combined high stability and h h-yielding performance.