Estimates of combining ability for agronomic traits in pepper (Capsicum annuum L.)

Abstract

Twenty-one F₁ hybrids were obtained from non-reciprocal crosses among seven genetically diverse pepper genotypes. The parents and F₁ (S were evaluated for combining ability and the relative importance of additive and non-additive gene action. The plants were grown in a greenhouse and the field using a randomized complete block design with three replications. Statistical analysis of general (GCA) and specific (SCA) combining ability was performed according to Griffing's diallel analysis method II, model I. The mean squares for GCA and SCA were significant for all traits with the exception of SCA for fruit yield (field) indicating the importance of both additive and non-additive gene action. Parents with elongated-fruit, large size and thick pericarp exhibited large positive GCA effects, and round, small and thin pericarp parents exhibited high negative GCA effects for these characters. Crosses with significant SCA effects in desired directions and high mean performance were also identified. The preponderance of GCA effects for various characters indicated that the characters will respond favorably to direct selection. In regard to parent selection, our results indicate that Pepper 1976 could be used to improve most of the fruit traits studied in this set of diallel crosses.