Nature of gene action and combining ability effects for grain yield and quality traits in rice (Oryza sativa L.)

Abstract

Combining ability, along with heterosis was elucidated for nine yield attributing and 10 grain quality traits in a set of 40 rice hybrid combinations derived from 13 parents using Line × Tester mating approach. The analysis of combining ability unveiled significant GCA and SCA variances, highlighting the importance of both additive and non-additive genetic components. The ratio of dominant genetic variance to additive genetic variance exceeded unity, indicating the prevalence of non-additive gene action in governing the inheritance of all examined traits. The parental line CO 55 and the testers IC 457996 and IC 208262 were recognized as good combiners for the majority of yield-related and grain-quality traits. Regarding per se performance, heterosis, and sca effects, the crosses CO 55 × IC 457996, ADT 54 × IC 115439 and ADT 54 × IC 115439 were found promising. Consequently, these combinations could be exploited for recombination breeding aimed at developing early maturing, high-yielding fine-grain rice varieties with market acceptance.

Keywords

• combing ability
• line x tester
• gene action
• heterosis
• rice