Genetic divergence of cowpea in the south of Tocantins

Abstract

In face of the increasing population growth and the importance of cowpea as a source of basic supply of many populations, there is a need for further studies to assist the development of improved genotypes. Therefore, the objective of this study was to evaluate the genetic divergence of twenty-four cowpea genotypes in the State of Tocantins, aiming the indication of the most promising combinations to integrate a breeding program for low level of technology conditions. The study was conducted in randomized blocks design, with three replications and 24 treatments. For the analysis of genetic divergence, the following parameter were analyzed: flowering date, days to pods maturation, number of pods per plant, number of grains per pod, pods length, grains index, weight of a hundred grains and grains yield. The genetic divergence was obtained by Mahalanobis distance and the genotypes grouped by the Tocher and UPGMA methods. Different combinations that can generate promising populations to be used in breeding programs were identified, namely those between the MNC03-725F-3 and MNC03-737F-5-4 genotypes and between MNC03737F-5-11 and MNC03-737F-5-4 genotypes. They are promising populations concerning productivity of grains in Cerrado conditions in Tocantins.