Analysis of Genotype-by-Environment Interaction in Advanced Genotypes of Barley using AMMI and BLUP-Based Indices

Multi-environment trials and study genotype-by-environment interaction have a fundamental role in the selection of the high yielding and stable genotypes across different environments before its commercial release.

In the present study, 19 barley genotypes were evaluated across four research stations including Moghan, Zabol, Gonbad, and Darab in a randomized complete block with three replications in terms of the number of days to heading, number of days to physiological maturity, grain filling period, plant height, 1000-grains weight and grain yield during 2020-2021 cropping season.

Statistical analyses showed a significant difference among environments, genotypes, and their interaction for grain yield and other measured traits. The likelihood ration test (LRT) showed significant effect for genotype-by-environment interaction on grain yield and other agronomic traits, hence, the best linear unbiased prediction (BLUP) analysis was computed. The values of estimated genetic variance components based on the BLUP model showed that the genotype-by-environment interaction (GEI) effect accounted for a high portion of phenotypic variance in all measured traits. Furthermore, plant height, 1000-grains weight and grain yield showed the highest values for broad heritability compared with other measured traits. Based on the multi-traits stability index (MTSI), genotypes G5, G6, G8, and G17 were identified as the most stable genotypes. Besides, the biplot rendered based on grain yield and the weighted average of absolute scores for the best linear unbiased predictions of the GEI recognized G5, G9, G10, and G17 as high-yielding and stable genotypes compared with others.

In conclusion, our results revealed that genotype G5 has the most general adaptability, and other identified genotypes showed specific adaptation with some of the warm regions in the south and north of the country. Hence, this genotype can be introduced as a high-yielding and stable commercial cultivar after an investigation of its stability over various years.