Genetic divergence among papaya accessions by morphoagronomic traits

Abstract

This study aimed to quantify genetic variability among 46 accessions of papaya from ‘Solo’ and ‘Formosa’ groups using 19 morphoagronomic traits separately and simultaneously, and to evaluate the efficiency of simultaneous analysis. The experiment was conducted for three growing seasons (May and August 2007, and November 2008), in Linhares-ES, using a randomized block design with two replications and 20 plants in two rows per plot. Quantitative traits were analyzed by analysis of variance and then used to estimate the Mahalanobis distance, while for the qualitative traits it was used the coefficient of simple coincidence. The genetic distance for the joint analysis was estimated based on the algorithm of Gower. The matrices of distance were compared using the Mantel correlation with 1000 permutations. The clusters of accessions were performed by UPGMA. Although they have made the same number of groups (seven), both types of variables separately and jointly did not allow the formation of groups substantially similar to the group ‘Formosa’. On the other hand, the accessions of ‘Solo’ group were allocated practically in the group I for all distance used. The cluster formed by the data simultaneously provided greater disjunction of accessions, due to greater homogeneity within groups and heterogeneity among groups.