Assessment of genotype × environment interaction and yield stability of grain maize (Zea mays L.) hybrids

Understanding the genotype × environmental interaction in the maize (Zea mays) breeding programs is necessary for finding high yielding and stable yield genotypes for different environmental conditions, enhancing breeding efficiency and crop productivity. To identify early-maturing maize hybrids that possess both high yield and yield stability, ۱۱ hybrids including four promising three-way crosses and seven promising single crosses along with three single-cross hybrids (cv. Dehghan, cv. Fajr, and cv. Koosha) as control were evaluated across nine locations over two consecutive growing seasons (۱۸ environments). The experimental design was randomized complete blocks with four replications. Phenological traits including silking, anthesis and physiological maturity dates, as well as grain yield, and yield components were measured and recorded. Combined analysis revealed significant effects of hybrid, growing season, location and their interaction on grain yield, emphasizing on the necessity of multi-environment trials to identify superior and stable yield grain maize hybrids. Grain yield showed positive correlation with all traits, except for cob percentage and kernel moisture content. The yield stability analysis using different yield stability indices showed high variation among hybrids. The hybrids were ranked based on grain yield and eight stability indices. Hybrids H, H۱۱, H۲, H۴ and H۵ achieved higher rank and were grouped as stable yield hybrids. The GGE biplot divided nine experimental locations into two major sectors and identified H۸, H۱۱, H۱۰, H۵ and H۴ as winning hybrids adapted to specific environments. The first sector included Karaj, Miandoab, Kerman, Moghan and Sari with H۱۱ and H۸ and H۴ as the winning hybrids, and the second sector comprised Shiraz, Isfahan, Kermanshah and Mashhad where H۵ and H۱۰ were the best-performing hybrids. The visualization of the ideal genotype demonstrates that H۴ followed by H۱۱ were located in close proximity to the ideal genotype. The single cross hybrid H۱۱ (KE ۷۶۰۰۹/۳۱۲ × K ۱۲۶۴/۵-۱) and the three-way cross hybrid H۴ (KE ۷۷۰۰۸/۱ × KSC۲۶۰) performed significantly different from the control hybrids, producing the highest grain yield of ۱۱.۴۴۷ and ۱۱.۲۳۸ t ha-۱, respectively. The GGE biplot and complementary yield stability analyses consistently identified H۱۱ and H۴ (from the FAO group ۴۰۰) as desirable hybrids with high stable grain yield, therefore suitable for being commercially released.

کلیدواژه ها:

Maize ، Early maturity ، stable yield genotypes ، Specific Adaptation ، GGE biplot Analysis