The experiment was conducted during May to December, 2024–2025 main seasons at mid-altitude bread wheat growing agro-ecologies of Ethiopia to study the agronomic performance, genotype-by-environment (G×E) interactions, heritability, cluster and correlation of bread wheat breeding genotypes across 11 multi-environment trials (METs).Utilizing an alpha lattice and partially replicated design, the study employed Factor Analytic Mixed Models (FAMM) and GGE biplot analysis to partition variance, GxE and identify drivers of yield stability. Grain yield ranged significantly from 1.60 to 6.50 t ha-1, underscoring substantial phenotypic plasticity across the environments. Results indicated that 55.80% of genotypes exceeded the grand mean yield, 77% yielded above 4.5 t ha-1, and 20% outperformed the standard check “Melka.” While grain yield exhibited high heritability (H2) ranged 16.48%–92.19%), traits like days to heading (DTH) and plant height (PHT) remained genetically stable (H2 > 85%). GGE biplot analysis partitioned testing sites into distinct mega-environments, identifying locations 25BWOPNMKU, 24BWPNMAB and 25BWOPNMAA as the most discriminative testing sites for selection. Although genotype EBW190004 achieved the highest mean yield (5.52 t ha-1), it showed high environmental sensitivity. Conversely, EBW190128 and EBW190063 were the most stable genotypes. Notably, EBW222059 appeared as the promising candidate for regional release, balancing high productivity (5.44 t ha-1) with exceptional resilience in moisture-constrained environments. Furthermore, the study confirmed high potential for genetic gain and demonstrated that the FAMM-based MET analysis provided a robust framework for identifying superior genotypes in bread wheat breeding programs across the mid-altitude regions of Ethiopia.
Bayisa Asefa, Berhanu Sime, Habtemriam Zegeye et al.· International Journal of Bio...· 0 citations
The experiment was conducted during July–November in 2023 main cropping season at Kulumsa Agricultural Research Center to assess the extent of genetic variability and the association among traits in bread wheat genotypes. Analysis of variance revealed significant genetic variation (p<0.01) among genotypes for seven of the nine studied characters. Grain yield exhibited the widest range, varying from 891(EBW232651) to 1682.5 (EBW232625) kg ha-1, with an average of 1325.96 kg ha-1. Encouragingly, 78% of studied genotypes exhibited superior grain yield compared to check Balcha (1242.5 kg ha-1). A moderate range of PCV and GCV were obtained for agronomic score, grain yield and thousand kernel weight, offer the most significant potential for improvement through selection. The high broad-sense heritability observed for days to heading days to maturity, hectoliter weight and thousand kernel weight, and traits with high GAM viz. grain yield and agronomic score, suggested a significant role of additive gene action in controlling these traits. Grain yield exhibited strong positive and highly significant correlations (p<0.01) at both genotypic (rg) and phenotypic (rp) levels with Agronomic Score, Thousand kernel weight and hectoliter weight. Grain yield displayed a strong negative and highly significant correlation (p<0.01) at both genotypic and phenotypic levels with yellow rust severity. The negative correlation with yellow rust severity emphasized the need to prioritize resistance breeding to protect yield potential from this disease. This finding suggested that selecting for improved agronomic score, hectoliter weight, and thousand kernel weight could be effective indirect selection strategies for enhancing grain yield in this breeding population.
Demeke Zewdu, Gadisa Alemu, Ruth Duga et al.· International Journal of Bio...· 0 citations
