Produção, qualidade e divergência genética para caracteres da qualidade da vagem imatura em feijão-caupi

Abstract

Cowpea, also known as string bean, is one of the main plant foods for smallholder farmers in the northern and northeastern regions of Brazil. The market for green pods and beans has been growing steadily and represents an alternative to the dry bean market. However, local cultivars with low productivity and commercial quality predominate in the market. Given the limited information available on immature pod production, this study aimed to evaluate the agronomic potential of cowpea genotypes for green pod production in the Cerrado. Two experiments were conducted: one in the experimental area of the Federal University of Tocantins, located on the Gurupi Campus in Tocantins, and the other at the Federal Institute of Education, Science, and Technology of Tocantins, located on the Dianópolis Campus in Tocantins. In each growing year, the performance of twenty genotypes was evaluated based on pod harvest, using a randomized block design. After harvest, the following traits were evaluated: pod length, pod width, number of grains per pod, number of pods per plant, 100-grain weight, pod weight, wet weight, dry weight, pod moisture content, and pod yield. Multivariate analysis was also performed to define genetic parameters for selection. After determining a significant difference between treatments, the Scott-Knott test was performed at 5% probability. The results indicated significant differences in genotype performance between cultivation locations, with emphasis on the genotypes MNC11-1013E-33 and MNC11-1013E-35, which presented greater pod length and number of grains per pod, especially in Dianópolis. The genotype x environment interaction was significant for the traits of pod length, pod weight, and grains per pod, demonstrating the importance of local adaptation for genotype selection when the objective is the production of immature pods. Pod productivity is the main distinguishing characteristic of genotypes, being strongly influenced by the number of pods per plant and the pod's wet weight. Analyses of morphological attributes were essential in discovering potential materials for creating new cultivars.