Phenotypic variation and traits interrelationships in bread wheat (Triticum aestivum L.) genotypes in Northern Ethiopia

Abstract

Information on phenotypic variation helps to breed better varieties. Forty-nine bread wheat genotypes were evaluated in simple lattice design at Jamma and Geregera to determine the extent of variation and association among 11 traits. Analysis of variance showed significant differences (p 0.01) among the genotypes for all traits, indicating the presence of adequate variability. Maximum values of genotypic coefficients of variation were recorded for spike length (8.66 %), number of productive tillers (8.4 %), number of grains per spike (6.4 %) and thousand-seed mass (6.15 %); this also shows the presence of substantial variability for these traits. Genetic parameters of the study revealed that days to heading, plant height, spike length, number of grains per spike and thousand-seed mass had moderate to high heritability and genetic advance as percent of the mean. Therefore, direct selection could be practiced to improve bread wheat for these traits. Moreover, selection of early-cycle lines which can escape the negative effects of climate change will be possible. Grain yield had strong and significant positive correlation with thousand-seed mass (rg = 0.395), biological yield (rgv= 0.617) and harvest index (rg = 0.731); selection based on these traits will be most effective in future bread wheat yield improvement programs as they also exerted strong positive direct effects on grain yield.