Inheritance pattern of Qualitative traits, Genetic analysis and association of yield attributes in F2 populations of Rice (Oryza sativa)

Abstract

Understanding the extent of genetic variability within the segregating generations is crucial for identifying superior segregants with high yield and better market acceptability. Thus, the present study was carried out to quantify the extent of genetic variation available in the segregating population of rice. Three crosses, viz., CO 55 × IC 457996, CO 55 × IC 464685, and CO 55 × IC 115439 were evaluated using a non-randomized experimental design for six yield attributing and two physical grain quality traits in F2 generation. The inheritance pattern of basal leaf sheath colour and grain colour in CO 55 × IC 115439 indicate digenic complementary gene interaction (9:7), whereas grain colour in CO 55 × IC 464685 exhibits inhibitory gene action (13:3). The positively skewed nature of productive tillers per plant and single-plant yield in the F2 segregants emphasizes the need for intensive selection to facilitate rapid improvement due to the influence of complementary gene action. Moderate to high GCV with high heritability and GAM for traits such as plant height, productive tillers per plant, hundred seed weight, grain width, and single-plant yield in the F2 segregants underscore the prevalence of additive gene action and thus provide the most effective condition for simple phenotypic selection. Moreover, productive tillers per plant and single-plant yield showed a strong positive association in all the crosses. Therefore, productive tillers per plant can be considered an indicator trait when selecting high-yielding segregants for grain yield improvement.