Grain iron and zinc density in pearl millet: combining ability, heterosis and association with grain yield and grain size uri icon


  • Genetics of micronutrients and their relationships with grain yield and other traits have a direct bearing on devisingeffective strategies for breeding biofortified crop cultivars. A line × tester study of 196 hybrids and their 28 parentallines of pearl millet (Pennisetum glaucum (L.) R.Br.) showed large genetic variability for Fe and Zn densities withpredominantly additive gene action and no better-parent heterosis. Hybrids with high levels of Fe and Zn densities,involved both parental lines having significant positive general combining ability (GCA), and there were highlysignificant and high positive correlations between performance per se of parental lines and their GCAs. Therewas highly significant and high positive correlation between the Fe and Zn densities, both for performance perse and GCA. Fe and Zn densities had highly significant and negative, albeit weak, correlations with grain yieldand highly significant and moderate positive correlation with grain weight in hybrids. These correlations, however,were non-significant in the parental lines. Thus, to breed hybrids with high Fe and Zn densities would require incorporatingthese micronutrients in both parental lines. Also, simultaneous selection for Fe and Zn densities based on performanceper se would be highly effective in selecting for GCA. Breeding for high Fe and Zn densities with large grain sizewill be highly effective. However, combining high levels of these micronutrients with high grain yield would requiregrowing larger breeding populations and progenies than breeding for grain yield alone, to make effective selection fordesirable recombinants

publication date

  • 2014