Estratégia para avaliação do cozimento dos grãos de progênies de feijoeiro e estimativas de parâmetros genéticos e fenotípicos

Abstract

A common bean recurrent selection (SR) program with a view toward yield and the carioca type grain aspect (beige with brown stripes) has been conducted since 1990. The question is whether there is still genetic variability after cycle thirteen (CXIII) for continuity of the program. In addition, in recent years, a great deal of attention has been directed toward the cooking and nutritional quality of foods. Furthermore, the modern family routine is increasingly hectic and time for food preparation has decreased substantially. Therefore, in addition to favorable agronomic traits, it is important that new common bean cultivars have good cooking properties. The methodology available for evaluating the cooking suitability of grains presents the restriction of the time spent on each evaluation, which makes it unviable for use in evaluating a large number of progenies in a short time. Thus, the aim of this study was to propose a new, more efficient methodology for evaluating the cooking trait of grains, and estimate the genetic and phenotypic parameters of CXIII of the SR program that allow inferences regarding the possibility of continuing to have success not only for yield and grain type, but also for cooking time. A total of 252 S0:2 progenies and four controls were evaluated in a 16 x 16 lattice design in three locations (Lavras, Patos de Minas and Lambari) sown in November 2012. The traits evaluated were yield, cooking suitability and carioca type grain aspect. The new cooking evaluation strategy proved to be efficient because it allowed a large number of progenies to be evaluated rapidly. After thirteen SR cycles, there is still genetic variability in the population for the traits evaluated. The lack of association between grain yield and cooking percentage or type of grains shows that it is possible to select progenies with high yield, with excellent grain aspect and good cooking capacity by using a selection index. It is also noteworthy that for all three traits, the mean value of the progenies is greater than that of the controls, which shows their potential for advantageously replacing the currently traded cultivars in the near future.