Analysis of quantitative trait distribution and nutritional variability in Rice (Oryza sativa L.) F₂ population

Rice (Oryza sativa L.) is one of the most important staple food crops and serves as the primary energy source for more than half of the global population. Improvement of grain yield along with nutritional quality traits such as iron (Fe), zinc (Zn) and protein content has become an important objective in rice breeding programmes. The present investigation was undertaken to study the genetic architecture and frequency distribution of yield and nutritional traits in the F₂ population derived from the cross CO54 × Kalanamak. A total of 238 F₂ segregants were evaluated for seventeen quantitative traits related to yield and grain nutritional quality. Considerable variability was observed among the segregating plants for all the traits studied. High variance was recorded for total grains per panicle (2570.30), filled grains per panicle (1811.94) and plant height (230.99), indicating wider genetic variability. Skewness values ranged from -0.68 to 0.96, suggesting the involvement of additive and non-additive gene action. Positive skewness was observed for most traits including flag leaf width, protein content and number of productive tillers, indicating the possibility of obtaining superior segregants through selection. Most of the characters exhibited platykurtic distribution, revealing polygenic inheritance and broad variability within the population. The results indicated that the CO54 × Kalanamak F₂ population possesses substantial variability for yield and nutritional traits and can be effectively utilized for selection of superior recombinants and development of bio-fortified rice varieties.