Genotype × Environment Interaction and Selection of High Yielding Wheat Genotypes for Different Wheat-growing Areas of Ethiopia

Abstract

Evaluation of wheat genotypes under different environments is essential for testing stability of their performance and range of adaptations. Where, enhanced grain yield has been achieved in bread wheat (Tritium aestivum L.) through the development of adaptable, high-yielding, and rust-resistant genotypes by evaluating advanced genotypes for yield in multi-environment trials. The adaptability of a genotype over diverse environments is usually tested by the degree of its interaction with different environments under which it is grown. This study examines fifteen bread wheat genotypes for two consecutive years (2016 and 2017) across eight locations in Ethiopia. The experiment was laid out using a Randomized Complete Block design and replicated three times intending to determine high-yielding advanced genotype and release best performing genotypes as a variety for the end-user. Highly significant (P ≤ 0.001) effects of genotype, environment, and genotype by environment interaction were observed for grain yield. The AMMI analysis of variance indicated that environments accounted for 52.34% of the total sum of squares for grain yield (genotype yields ranged from 5.76 t/ha at E-11 to 1.31 t/ha at E-7). followed by interaction (22.95%) and genotypes (11.31%).The genotype ETBW8260 (G4) exhibited high mean grain yield and well performed to the tested environments. The ETBW8260 (G4) was selected as early maturing, high yielding, resistant to yellow rust and fitting for low to midland wheat growing areas and has a yield advantage over the standard Ogolcho and the local Kakaba. Both locations and genotypes are dispersed widely in all quadrants in the AMMI-1 biplot. As per the YSI Ogolcho (#15) ETBW8303 (G2), ETBW8454 (G12), ETBW8261 (G5), ETBW8406 (G10), ETBW8310 (G3), and ETBW8260 (G4), the genotypes of bread wheat were stable. Besides, the genotype ETBW8260 (G4 has highest mean yield with good stability. Therefore, after a one-year variety verification trial, ETBW8260 is released as a commercial variety in 2019 and a designated local name called “Balcha” and recommended for low-medium part of wheat production agroecology of the country.