Combining ability for agronomic traits in snap bean

Abstract

To develop a plant breeding program, information about parentals per se performance and also about genotypes combining ability is an important step. Crosses involving snap and common beans are usual in breeding snap beans since both belong to the same species and many times common beans genotypes have interesting traits to be transferred to snap beans. The aim of this work was to evaluate the combining ability among four snap beans and one common bean genotypes considering agronomic traits. The genotypes were chosen based on genetic divergence and desirable agronomic traits. Crosses in a complete diallel without reciprocals design were performed. Eight agronomic traits were evaluated under field conditions from November 2007 to February 2008, in a randomized block design, with four replications, in Tangará da Serra, Mato Grosso, Brazil. The parents ‘UEL 1’ and ‘Novirex’ had the best performance and were indicated to start breeding programs aiming to develop promising populations. The combinations ‘Manteiga Baixo’ x ‘Novirex’ and ‘Manteiga Baixo’ x ‘UEL 1’ had the best results considering Specific Combining Ability. Yet, these combinations were originated from ‘UEL 1’ and ‘Novirex’, the two parents with superior General Combining Ability and also the best mean values.