Wheat Triticum aestivum L. is one of the most important agricultural products, and meets the highest nutritional needs of humans in various countries. This study aims to evaluate the compatibility and stability of 25 wheat genotypes for two crop years in five regions (Karaj, Qazvin, Isfahan, Varamin and Damavand) in a randomized complete block design with three replications. The results of variance analysis in the additive main effects and multiplication interaction (AMMI) method showed that the effect of genotype and the genotype × environment interaction in the first, second, and mean two crop years had a significant difference at the level of one percent probability. Based on the results obtained from the first and second principal components, G8, G4 and G22 genotypes were identified as superior genotypes. Isfahan was an ideal environment for this study. The results obtained from the comparison of the Duncan method showed that G14, G12, and G1 genotypes had suitable ranks. Graphical analysis was used to study the genotypes of wheat and the environment, and the genotype × environment interaction. Based on the ranking genotypes in the first and second principal components and an average of two years, G2 and G21 genotypes were identified as high yielding, and G21 genotypes as stable. G18 and G23 genotypes were selected as the best genotypes in all three experimental periods, based on the multidimensional diagram. The results of the ideal genotype diagram were G12 and G21 genotypes; and based on the results of the ideal environment diagram, Damavand and Varamin environments were identified as ideal environments. AMM1 covered 69.6% and AMMI2 75.6% of the data variance in the first year of the experiment. In the second crop year, 78.1% of the total variance of the data was explained based on the AMMI1, and 71.1% based on the AMM2.

This study was conducted to investigate the response of maize hybrids to drought stress and to select the most drought-tolerant cultivar compared to other hybrids. The experiment was performed on six maize hybrids in a randomized complete block design (RCBD) with three replications under regular irrigation and limited irrigation in the vegetative and reproductive stages in Iran. Drought tolerance indices (TOL, MP, GMP, STI, SSI, and HAR) for the grain yield of genotypes were calculated, and principal component analysis was based on them. The results obtained from estimating the indices showed that the SC647 and KSC704 hybrids, while having good performance in both conditions, also have drought tolerance. Examining the correlation between drought tolerance indices and yield in both conditions, among the indices used to detect drought tolerance, STI, MP, and GMP indices can be considered suitable for selecting high-yielding hybrids in these conditions. The principal components analysis on the stress-tolerance index showed that MP and GMP indices could be used as the best indices with high coefficients to select stress-tolerance hybrids. SC647 and KSC704 hybrids were identified and selected as hybrids with high tolerance to moisture stress. The results of drought tolerance indices in the emergence stage of the crest showed that the KSC260 hybrid has the lowest level of stress sensitivity. SC647 hybrids showed the lowest susceptibility to drought stress in the ear emergence stage.

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The present study investigated the stability and adaptability of maize (Zea mays L.) hybrids. In this study, 12 maize hybrids were planted and examined considering the grain yield. The experiment was arranged in a randomized complete block design (RCBD) with three replications in four research stations in Iran during two crop years. The combined analysis of variance showed that genotype-environment interactions were significant at one percent probability level. The grain yield can stabilize, and hybrids with specific adaptability are recommended to each environment. Hybrids with specific adaptability can be recommended to all types of the environment. Means comparison yield of the genotypes identified DC370 as a high-yield genotype. Regarding AMMI analysis, genotype × environment interactions (GEIs) and two first components were found significant. The SC647 genotype was identified as the most stable genotype. Regarding the stability parameters, SC647 and KSC705 genotypes were selected as the most stable genotypes. From AMMI1 and AMMI2 graphs, the SC647 genotype was identified as the most stable genotype compared with other hybrids.

Genotype × environment interaction is one of the complex issues of breeding programs to produce high-yielding and compatible cultivars. Interaction of genotype × environment and make the more accurate selection, the performance and stability of hybrids need to be considered simultaneously. This study aimed to investigate stable genotypes with yield using 12 maize hybrids in different climatic conditions of Iran. The experimental design used was a randomized complete blocks design in three replications in two cropping years in Karaj, Birjand, Shiraz, and Arak stations. The simple analysis of variance performed on grain yield of genotypes indicated that all hybrids studied each year and station were significantly different in grain yield. Also, the combined analysis results showed a significant effect on the environment, the effects of genotype, and the interaction of genotype × environment and t in the studied hybrids different. Comparing Duncan's mean on the data obtained from the research, KSC705 genotypes with an average yield of 7.21 and KSC704 genotype with an average yield of 7.04 were identified as high yield cultivars. In order to identify stable cultivars, six stability parameters were used. KSC260 and KSC707 genotypes had stability Based on the environmental variance, also had stability based KSC705, KSC707 genotype on environmental the coefficient of variation, and KSC260 genotypes had stability based methods of genotype and environment interaction. As well as based on Eberhart and Russell regression coefficient had the stability to KSC400 and SC647 genotypes. Also, they were identified as the most stable genotypes based on the detection coefficient method, KSC707, and KSC703 genotypes.