Genotype and genotype by environment interaction (GGE) biplot analysis for assessing genotype stability in grain iron and zinc content of maize across diverse environments

Abstract

The bio-fortification of maize presents a promising approach for improving nutritional security. Considering iron and zinc deficiencies as significant global public health challenges, the present study included the multi-location evaluation of maize elite inbred lines (300) and hybrids (31) to see variability for iron and zinc content, quantify the genotypes-by-environment (GEI) interaction, and identify stable genotypes with high Fe and Zn content. The findings demonstrated significant GEI for both Fe and Zn, indicating diversity among genotypes and environments under study. Environmental effects were higher for Fe than on Zn. Ideal genotypes for Fe included hybrids H21 and H27, along with inbred G107 and G114. For Zn content, H27 and inbred G3, G178, and G9 emerged as the best genotypes. The analysis unveiled multiple mega-environments for Fe and Zn content, suggesting genotype adaptation to specific environmental conditions. These promising genotypes identified can be of great potential in breeding for high Fe and Zn in maize. Understanding the specific genetic and physiological mechanisms underlying the performance of hybrids and inbred lines with high as well as stable Fe and Zn content and winning genotypes within each mega-environment are crucial for targeted breeding strategies.