Assessment of genotype × environment interaction and stability for durum wheat (Triticum turgidum var. Durum) varieties in the Amhara Region, Ethiopia

Abstract

Durum wheat is an important cereal crop in Ethiopia; however, its productivity is constrained by strong genotype × environment interactions (GEI) and limited information on varietal stability across diverse production environments. Therefore, this study was conducted with the objective of understanding the relative contribution of GEI and assessing the stability of varieties in grain yield at Takusa, Dembia, Dabat, Debark, Debre-Tabor, and Moretina Jiru districts during 2018 main cropping season. Twelve durum wheat varieties were used on a randomized complete block design with three replications. Each experimental unit had six rows of 2.5 m in length with a spacing of 0.2 m. A seed rate of 150 kg ha-1 with the recommended fertilizer rate for the respective areas was used. Yield and yield-related agronomic data were collected and subjected to analysis of variance (ANOVA) over locations. Stability analysis of grain yield was executed using GGE biplot model. The combined ANOVA revealed highly significant differences among the varieties, environments, and GEI for grain yield and yield related agronomic traits. Based on the ‘which won where’ of the GGE biplot model, the locations were classified into two mega-environments. The first mega-environment consists of Moretina Jiru, Debre-Tabor, Takusa, and Dembia districts with the winning variety of Fetan. In contrast, the second mega-environment consists of Debark and Dabat district with the winning variety of Hitossa. Moreover, further study is recommended to confirm this finding by including more locations over several years.