STABILITY AND ADAPTABILITY OF RELEASED BREAD WHEAT (TRITICUM AESTIVUM L.) VARIETIES FOR YIELD AND YIELD RELATED TRAITS AT HIGHLANDS OF SOUTHWESTERN PART OF ETHIOPIA

Abstract

Bread wheat (Triticum aestivum L.) is the most important cereal crop in Ethiopia. Lack of
genotypes with wide stability across environments has been one of the most important
constraints of wheat production in the highlands of Southwestern part of Ethiopia. The objectives
of the trial was to estimate the magnitude of GEI and to select high yielding and stable bread
wheat varieties for the highlands of Southwestern Ethiopia using different stability analysis.
Twelve nationally released bread wheat varieties were obtained from Kulumisa Agricultural
Research Center (KARC) used for the study. The varieties were evaluated in three environments,
over two main growing seasons (2021 and 2022), in the highlands of Southwestern Ethiopia. The
experiment was laid out in randomized complete block design (RCBD) with three replications.
The experimental plot for each variety consisted of six rows of 2.5m length and rows were
spaced 20cm apart. Spacing between rows, plots and replications 25cm, 30cm and 1m
respectively. The seed rate was 125kg/ha. Fertilizer was applied at rate of 100kg NPS and 150kg
of urea was applied in spilt: half at the time of planting and the remaining half at the tillering
stage. In addition, other relevant field trial management practices were carried out uniformly for
all experimental units. The analysis of variance (ANOVA) revealed that there was a highly
significant difference (p<0.001) among grain yield across locations. The mean grain yield of
wheat varieties ranged from 3.5t/ha (Ogolocho) to 4.6t/ha (Danda’a) with mean grain yield of
3.8t/ha. The combined ANOVA over environments for grain yield was highly significant
(p<0.001) for genotypes, environments and interaction effects. The effect of environment,
genotype and GEI accounted for 77.6%, 3.87% and 10.57% of the total sum squares. According
to both univariate and AMMI stability model analysis, bread wheat variety ETBW9089 was
stable and recommended for high scale production.