Genetic variability and correlation of kernel micronutrients among exotic quality protein maize inbreds and their utility in breeding programme

Abstract

Micronutrient malnutrition is a widespread problem known to affect millions of children and women. However, the adverse effects of micronutrient deficiency can be overcome through self-targeting, cost-effective and sustainable genetic biofortification approach, which is mainly based on staple food crops. Since maize has emerged as a prominent future crop especially for India, developing maize hybrids that are rich in kernel micronutrients will help in reducing the problems of micronutrient malnutrition. Here, we report variability of kernel Fe and Zn in 120 exotic Quality Protein Maize (QPM) inbreds and kernel Mn and Cu in a representative subset of 68 lines. A wide range of genetic variation was found among genotypes for all the kernel micronutrients: Fe (16.6-83.4 ppm), Zn (16.4-53.2 ppm), Mn (1.7-34.8 ppm) and Cu (0.5-9.5 ppm). Higher mean for kernel Fe and Zn in QPM inbreds suggests possible influence of opaque2 gene and/or modifiers present in them. Significant and positive correlation was observed among kernel Fe, Zn, Mn and Cu. Genetic diversity based on all four micronutrients grouped 68 lines into three major clusters with a mean coefficient of genetic dissimilarity of 2.46. Parental combinations were selected from different heterotic pools and maturity groups to develop high-yielding hybrids enriched with micronutrients.