Evaluation of genetic divergence in sweet potato by multivariate procedures

Abstract

This work was carried out at Epamig-CTZM experimental area in Oratórios, MG, during the summer of 1999, in order to evaluate the genetic divergence among 51 sweet potato clones from different Brazilian regions. A randomized complete block design with three replications was used. Each plot consisted of three rows of 3.0 m with the plants in the spacing of 1.00 x 0.25 m. The evaluations were done in five competitive plants located within an area of 2,0 m² in the central row. Genetic divergence, based in 25 characteristics, was estimated by the Mahalanobis generalized distance and by two grouping methods, the Tocher’s grouping and the hierarchical nearest neighbor. Large genetic variability was detected among the clones, which were then grouped into seven heterotic clusters by the two methods. There was good agreement in the formation of the groups for the two methods. The occurrence of small genetic distances among some clones and the inclusion of more than a clone into a specific group indicate that it might be occurring duplication among the evaluated genotypes might be occurring