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

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 ? and ? 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

Efficiency of GGE Biplot and AMMI Analyses for Adaptability and Grain Yield Stability of Durum Wheat Lines under Different Environments

Genotype × environment interactions make it difficult to release high yielding durum varieties for diverse environmental conditions. The main purpose of this study was to achieve high yielding durum wheat genotypes with higher yield stability in different environmental conditions, tolerance to environmental stresses such as cold damage, terminal drought, and heat stresses. Hence, 16 durum wheat lines were evaluated for grain yield stability and morphological traits in Maragheh, Sararood, Qamloo, Ardabil and Urmia Agricultural Research Stations in 2012-15. In each location, the experiments were conducted in a randomized complete block design with three replications. Based on combined ANOVA, there were significant differences among the environments (E), genotypes (G) and G×E. GGE-biplot analysis showed that the 14 environments belonged to 3 mega-environments, and different genotypes had higher yield in each mega-environments. The AMMI and GGE results also confirmed that genotypes 2 (G-1252) and 3 (61-130/414-44//…) were the most high-yielding durum lines with reasonable yield stability across environments. Also, genotype 10 was the most adapted genotype to Ardabil. Line 61-130/414-44//… had 60, 11, 31, 10 and 17% more yield than check line (Saji) in Maragheh, Sararood, Qamloo, Ardabil and Urmia under rainfed conditions, respectively. Hence, these lines can be candiates to release as new durum varieties for cold and moderate rainfed areas. Complementary irrigation could increase grain yield up to 14 and 68% in Maragheh and Sararood, respectively. It can be concluded that finding new stable high-yielding durum lines, with better performances, as compared to the existed varieties, is a great progress in durum breeding programs in cold rainfed areas. Moreover, the GGE biplot and AMMI analysis had good performance in adaptability and yield stability analysis in durum genotypes and could be used to evaluate durum genotypes at different locations over the years in durum breeding programs