Abstract:
The significant G x E interaction has been a challenge to bread wheat breeders as this interaction limits
accuracy of yield estimate, identification of stable genotypes and further complicate selection of
genotypes. The objective of the study was to quantify the magnitude of genotype by environment
interaction and stability in yield and yield related traits and identify appropriate genotypes for the test
environments. Twenty bread wheat genotypes and two checks were evaluated at six test locations of South
Eastern Ethiopia 2013/1014 during main growing season in a randomized complete block design with
four replications.The combined analysis of variance showed significant differences (P< 0.01) for the
genotypes, locations and genotype by location interaction for traits studied. Non-significant differences
(P< 0.05) among genotypes were observed for the response variables, 1000 kernel weight and hectoliter
weight.AMMI is used to partition the G x E SS in the combined anova table in to its PCAs. Accordingly,
the first and second IPCAs share 60.77% and 15.70% of the G x E SS captures 20.68 %.The AMMI model
clearly indicate the genotype by environment interaction by partitioning into three significant component
taking 89.7% of genotype by environment variation 20.68% of the variation in the genotype by
environment interaction. According to the Stability analysis of the additive main effect and multiplicative
interaction, biplotanalysis ranking the genotype Digelu and ETBW6738 were the most stable coupled
with higher grain yield where as the genotypes Danda’aandETBW6732were unstable with lower mean
yield.Based on the AMMI, environments were highly variable both for main and interaction effects.
Bokoji, Asassa,Sinana,Kulumsa and Holeta were a favorable environments; whereas Areka as low
yielding (unfavorable) environments for majority of the traits. In general, the results of the analysis
showed that bread wheat is highly sensitive to environmental changes and this necessitates screening of
cultivars for wide and specific adaptation. Based on the one year data the varietyDigelu were stable
accompanied with higher yield, but in order to recommended appropriate genotypes to the south Eastern
Ethiopia repeating the experiment is vital..
