Variablity, heritability and genetic advance in quantitative traits of Tef [Eragrostis Tef (ZUCC.) Trotter]: implication for genetic improvement strategies

Abstract

Seventy nine tef populations collected from ten administrative regions and seven altitude classes were planted with two improved varieties in simple lattice design at Gute and Bako during 2007 and 2008 cropping season, respectively, to assess variability, and estimate heritability and genetic advance of quantitative traits. The combined analysis of variance across locations showed significant location effects on all the quantitative traits considered. The genotype mean squares were also significant (P≤0.01) for all quantitative traits except number of spikelet per panicle, number of internodes and number of fertile floret per spikelet at the top of main panicle. Genotype x Environment interaction was significant ((P≤0.01) for grain yield per plant, lodging index, harvest index, above ground weight and number of panicle branches. The phenotypic coefficient of variation was higher than the corresponding genotypic coefficient of variation for all quantitative characters considered in this study. This implies that; beside the genetic factors; environmental factors have high contribution for the variations observed. Genotype x Environment coefficient of variation was found to be less than the genotypic coefficient of variation for most of the quantitative characters. This indicates that variability observed in tef landraces was more due to the genotypic component than due to interaction between genotype and environment. Relatively, the higher heritability coupled with higher genetic advance noted for grain yield per plant, lodging index and biomass weight per plant in the study indicates the ease of phenotype-based selection for the improvement of these traits. However, low heritability range and genetic advance range were recorded for culm length, number of culm internodes per main shoot, days to maturity, number of fertile floret per spikelet at the top, middle and base of the panicle across the two locations. This implies that most of the variations for these traits were environmental rather than genetic.

Keywords/phrases: Eragrostis tef, Genetic advance, Heritability, Landraces, Variation

Ethiop. J. Biol. Sci., 7(2): 159-177, 2008