M. Karthik, S. Paul, J. Poornima, B. Srikanth, R. Kumar, A. Kumar Quality Protein Maize (QPM), grain yield, protein, lysine, tryptophan, regression analysis 112-125 10 (3) July 2026 The present study evaluated the relationships among grain yield, protein, lysine, and tryptophan contents in released Quality Protein Maize (QPM) hybrids using regression analysis, scatter plots, and correlation heat mapping. The results revealed predominantly positive linear associations among the studied traits, while grain yield showed weak correlations with nutritional quality attributes, indicating the feasibility of improving productivity and nutritional quality independently. Notably, lysine and tryptophan exhibited the strongest positive correlation (r = 0.615), suggesting a coordinated improvement of these essential amino acids associated with the opaque2 gene and its modifier genes. Regression analysis further indicated that grain yield explained only a limited proportion of the variation in nutritional traits, supporting the possibility of simultaneous improvement of yield and protein quality through appropriate breeding strategies. The comprehensive Hybrid Performance Index (HPI) identified JHQPM-16, JHQPM-20, and Pusa hybrids among the superior performers, demonstrating a desirable balance between high grain yield and enhanced nutritional quality. These findings emphasize the potential of integrated breeding approaches, for developing high-yielding and nutritionally superior QPM hybrids, thereby contributing to both food security and nutritional security objectives. Such efforts can strengthen the role of biofortified maize in addressing protein malnutrition while maintaining agronomic productivity.