Genotype by environment interaction analysis for grain yield of wheat in irrigated and rain-fed mega-environments using AMMI and GGE bipolt models

Abstract

Wheat (Triticum aestivum L.) is the major and strategic cereal crop globally. It is grown worldwide under a wide range of agro-ecological conditions. The performance of quantitative traits, for example grain yield, often varies due to significant effects of the genotype and environment interaction (GEI). Therefore, the integration of higher grain yield with stable performance is one of the common objectives in wheat-breeding programs. The present investigation was carried out to evaluate the GEI through GGE biplot and AMMI analysis over six environments (rain-fed and irrigated conditions during three years) using 29 diverse wheat genotypes. The analysis of variance revealed that the effect of environments (E), genotypes (G) and GEI are significant. The first two AMMI components justified 72.6% of the GEI variation. In the other hands, the first two principal components of the GGE biplot explained 58.3% of the observed variation for the grain yield. The GGE biplot suggested suitability of the tester E6 based on discrimination ability and representativeness, which is ideal for selecting superior genotypes. Based on the similar results of AMMI and GGE-biplot methods, the genotype G6 was the best performing genotypes at the rain-fed mega-environment. In addition, the entries G1 and G29 were suitable for the irrigated mega-environment.