Genetic Divergence and Selection of Genitors Aiming to Generate Variability in Common Bean Lines

Abstract

The objective of this work was to evaluate the genetic divergence between common bean strains from the breeding program of the Agricultural Research Institute of Mozambique (IIAM)-Zonal Centre (CZC) and to identify potential genitors to generate segregating populations with high average and wide genetic variability. Five common bean lines were evaluated in a randomized block design with three repetitions. The quantitative traits evaluated were leaf area index, days to 50% flowering, days to maturity, several pods per plant, 100 seed weight, and yield, while the qualitative traits were growth habit, epicotyl colour, leaf colour intensity, leaf roughness, fresh pod colour, grain colour, grain size, and flower colour. The data obtained were submitted to variance analysis and grouping of means by the Scott-Knott test. The relative importance of characters was evaluated by the Singh. Clustering was performed by the Tocher optimization method and distance projection in the 2D plane, using the generalized Mahalanobis distance as a measure of dissimilarity. The degree of preservation of genetic distances in the 2D plane was assessed by the Cohenetic Correlation Coefficient, distortion, and stress. The LPA54 and Bonus lines were highlighted by direct selection based on the performance per se of their characteristics. Genetic variability was checked for the trait’s days to 50% flowering several of pods per plant, and 100-seed weight and the strains were separated into two groups. The crosses between (G19833, LPA54, Manteiga, and Bonus) with the strain DOR364 there is the potential for obtaining hybrids with higher heterotic effect and segregating populations with high variability. The traits of 100-seed weight, pods per plant, epicotyl colour, and grain size were the most important in the discrimination of the strains