Heterotic potential of partial male sterile-based hybrids in finger millet (Eleusine corocona L.): Implications to genetic improvement

Finger millet, a nutrient-rich and climate-resilient cereal, faces declining cultivation due to poor productivity, largely because of the lack of effective hybridization techniques. A set of 46 hybrids developed through partial male sterile line PS 1 was evaluated in summer and kharif seasons. Significant differences were observed among hybrids and parents for 16 traits, with key yield traits showing strong genotype x environment (GxE) interactions. Heterosis for grain yield ranged from -41.7% to 58.1% during summer and -38.5% to 48.4% in kharif over the check variety GPU 28. Notably, the hybrid PS1 x GE 4972 exhibited stable heterosis 23.4% and 48.4%), respectively across both the seasons, while PS1 x GE 4764 (58.1%), PS1 x GE 436 (31.9%) and PS1 x MR1 (26.6%) showed season-specific heterosis. These hybrids showed highest heterosis, reported thus far in finger millet and indicated the crop’s potential for increased productivity. Promising heterotic hybrids were also identified for traits like fodder yield, ear head weight, and seed weight. High correlations between hybrid means and mid-parent values for traits like finger length, days to maturity, and seed weight suggested additive gene action. Genetic diversity analysis of 47 parents revealed substantial diversity and geographical clustering. However, no direct correlation was observed between heterosis and parental divergence based on morphological or SSR polymorphism. The present study is the first extensive heterosis investigation in finger millet demonstrating the potential of partial male sterility for improved hybridization and exploring broader genetic pools. The promising hybrids and parental lines offer new opportunities for finger millet improvement.