Divergência genética e importância de caracteres agronômicos em genótipos de feijão-caupi

Abstract

Cowpea has great socioeconomic and food importance, especially in the North and Northeast regions of Brazil. That said studies are needed to help the process of obtaining superior genotypes. The study aimed to assess genetic divergence, agronomic traits and promising combinations of cowpea genotypes. The experiment was conducted in a dryland condition in the experimental area of the Uruçuí Campus of the Federal Institute of Piauí-IFPI, in Uruçuí - PI, in a randomized block design with four replications. Ten genotypes were used, all of them commercial cultivars. The following agronomic traits were evaluated: cycle (days to maturity); number of pods per plant (nº); number of grains per pod (nº); mass of 100 grains (g) and grain yield (kg ha-1 ). The genetic divergence was obtained through the generalized Mahalanobis distance and the genotypes grouped by the UPGMA method. The BRS Tumucumaque, BRS Pajeú and BRS Guariba genotypes are promising for crops in the first harvest under conditions of low technological level of Cerrado in Piauí. The combinations between the BRS Tumucumaque genotypes with BRS Imponente, BRS Tumucumaque with BRS Aracê, BRS Guariba with BRS Imponente, BRS Guariba with BRS Aracê and BRS Pajeú with BRS Imponente are combinations suitable for obtaining promising populations regarding grain productivity in condition of Cerrado in Piauí. The weight characteristics of 100 grains, cycle and number of grains per pod were the ones that most contributed to the genetic divergence.