Stability analysis in bread wheat (<i>Triticum aestivum</i> L.) genotypes in north-western Ethiopia

Abstract

Northwestern Ethiopian is one of the areas that has been experiencing weather variability both from season to season as well as from place to place in the same season over relatively small areas. In such weather conditions, the magnitude of genotype x environment interaction is more important than the average performance of crop genotypes. Therefore, experiments were conducted at Adet, Simada and Debretabor in 2014 and 2015 cropping seasons under rain-fed condition with the objectives of evaluating the stability of bread wheat genotypes for grain yield, and estimate the magnitude of genotype x environment interaction on grain yield. The treatment consisted of twelve bread wheat genotypes, namely, Bolo (G8), Dand’a (G5), Gambo (G4), Gassay (G6), Hidase (G1), Huluka (G3), Kubsa (G12), Menze (G10), Ogolcho (G2), Shorima (G11), Tay (G7), and Tsehay (G9). The experiments were laid out as a randomized complete block design with three replications per treatment at each site. The analysis of variance revealed the significant (P ≤ 0.01) effect of genotype, growing season, location and all possible interactions of the three main factors. The results of AMMI analysis depicted significant (P ≤ 0.01) differences among genotypes across the environments. According to the study, the performances of genotypes grain yield were highly affected by environment and the genotype. The highest variation was accounted for location (29 %) followed by genotype (18%) and location by year (18 %) and genotype by year (12%) effects. Based on Additive Main effects and Multiplicative Interaction (AMMI), genotype and genotype by environment (GGE) biplot and stability coefficient analyses Ogolcho (G2), Gambo (G4), Shorima (G11) and Tsehay (G9) were relatively stable genotypes across the test environments than the checks, TAY (G7) and Kubsa (G12). Therefore, based on the stability and overall mean grain yield of genotypes, recently released genotypes Gambo (G4), Ogolcho (G2) and Tsehay (G9) and relatively older genotypes Shorima (G11) and TAY (G7) could be recommended for production at the test environments in the Western Amhara Region.

Keywords: Additive Main effects and Multiplicative Interaction (AMMI); Genotype and Genotype by environment (GGE); Grain Yield and Stability coefficient