Genetic variability for Yield and Yield Related Traits in Orange-fleshed Sweetpotato Genotypes Evaluated at Hawassa, Ethiopia

Abstract

The study was conducted to determine variability for yield and yield related traits in 24 orange fleshed sweetpotato [Ipomoea batatas (L.) Lam] genotypes in the 2017 main cropping season at Hawassa Agricultural Research Center. The experiment was laid out in a Randomized Complete Block Design with three replications. Data were collected on 19 traits and analysis of variance (ANOVA) was conducted. Significant differences (p≤0.05) among genotypes were observed for root yield and its components as well as morphological and qualitative traits including sweetpotato virus disease reaction (SPVD). The phenotypic coefficient of variation (PCV) ranged from 22.1% for mature leaf size to 118.3% for unmarketable root yield, while the genotypic coefficient of variation (GCV) ranged from 20.6% for root girth to 111.7% for unmarketable root yield. All the traits studied showed PCV and GCV more than 20%, suggesting high variability and this could be used for the selection of superior genotypes concerning character of interest. Most traits showed high values for broad-sense heritability, which ranged from 66.7 to 100%, indicating low environmental influence in the observed variation. High heritability coupled with high genetic advances as a percent of mean was observed for marketable root yield, root skin color, root beta carotene content, harvest index, vine length, vine inter-node length and above ground fresh weight, implying these characters are governed by additive gene action and selection would be rewarding for the further improvement of such traits.