The study was conducted to evaluate the effect of GEI and its magnitude on the grain quality of bread wheat genotypes in
Ethiopia. 15 bread wheat genotypes were evaluated using RCBD with four replications at six different locations in Ethiopia
during 2017/18 cropping season. Combine Analysis of variance showed highly significant (P<0.001) differences among
genotype, environment and GEI for investigated quality traits except GEI shows non-significant difference in dry gluten and
gluten index. The environment contributed more than 50% only in PC (83.6%) and HLW (56.1%). The three components,
G, E and GxE made almost similar contribution to most of the quality traits (WG, DG and GI), although the contribution
of the environment was a little higher. Hardness index was determined mainly by the genotype (69.3%). The contribution
of GxE was higher than that of genotype in all quality traits except in HDI and GI, again indicating the important role of
GxE in the determination of wheat quality traits. Genotype ETBW9045 and ETBW8065 gave the best value of protein in
the favorable means (15.05% and 14.75%) respectively. The Hidase had the highest value of wet gluten (58.2%) and dry
gluten (24.38%) in average for all investigated locations (58.2%). GGE biplot declared ETBW9045 (#10) and ETBW8065
(#6) genotypes as stable in all quality. These two genotypes ETBW9045 (#10) and ETBW8065 (#6) are recommended for
wide adaptation and for crossing. This study demonstrates success in wheat breeding for improved quality in bread wheat.
The study also provides information on the combined stability of improved quality of the nationally important bread wheat
genotypes. Therefore, the results of this study could be valuable for national bread wheat breeding programs to develop
new varieties with high stable grain quality.
Improvement of Grain Quality Traits in Bread Wheat Genotypes Through Mutation Breeding Using Gamma Irradiation
