UNLOCKING HYBRID POTENTIAL: A DETAILED ANALYSIS OF HETEROSIS, GCA, AND SCA FOR ENHANCING AGRONOMIC PERFORMANCE AND YIELD IN RICE (ORYZA SATIVA L.)

This study evaluates heterosis, general combining ability (GCA), and specific combining ability (SCA) in rice hybrids to assess key agronomic traits.Heterosis, or hybrid vigor, is pivotal in enhancing agronomic traits of rice hybrids.This study evaluates heterosis for critical traits, including days to 50% flowering, days to maturity, plant height, number of grains per panicle, and grain yield, essential for increasing rice productivity and sustainability.Results indicate significant variations in heterosis across hybrid combinations.Notable positive mid-parent heterosis was observed in MTU1197 X BLM9 (9.65%) and PKV HMT X BLM9 (8.90%), suggesting potential for breeding early-flowering rice varieties.Conversely, R2404-346-164-1 X ISM (Improved Samba Mahsuri) displayed significant negative mid-parent heterosis (-13.77%), as did other combinations such as MTU1197 X DRR Dhan 62 (-11.00%) and Swarna X ISM (-9.60%).For plant height, R1853-105-1-82-1 X ISM achieved a significant mid-parent heterosis of 25.90 %, while the combination R2404-346-164-1 X ISM reached 24.23%.The analysis of grain yield per plant with notable findings such as RFS2019-1 X ISM showing a positive better-parent heterosis of 16.15% and Swarna X DRR Dhan 62 reflecting negative heterosis (-19.95%).GCA analysis identified DRR Dhan 62 (-6.587) and MTU1197 (-5.08) with significant negative effects for early flowering, while BLM9 (8.460) promoted delayed flowering.Cross R1853-105-1-82-1 X ISM emerged as the best combination for plant height and grain yield, showing positive SCA effects (17.39 for grains per panicle).These findings emphasize the importance of grain yield and plant height in selecting superior hybrid combinations.This work will be valuable for rice breeding programs aiming to enhance productivity and adaptability in diverse environmental conditions.