Genetic diversity between native cupuízeiros from Portal da Amazonia, Mato Grosso, Brazil

Abstract

Theobroma subincanum Mart. popularly known as cupuí, belongs to the family Malvaceae. It is a wild fruit species native to the Amazon and is found in mainland forests, being characterized by its great alimentary and ecological importance. The cupuí presents genes that can be used for the croop breeding of commercial species of the genus, so that many studies have been carried to characterize genotypes through molecular markers, among which ISSRs (Inter Simple Sequence Repeats) have been widely used. In this context the objective of the study was to analyze the genetic diversity among cupuí genotypes, using molecular markers ISSR. Ten markers used amplified 42 fragments, being 35.71% polymorphic, and the genetic dissimilarity, estimated from the Jaccard coefficient, varied from 0.02 to 0.26, indicating the existence of genetic variability among the studied genotypes. The UPGMA grouping method allocated the twenty genotypes of cupuí analyzed in three groups, while the Tocher optimization method distributed the same in eight groups, thus confirming the existence of genetic diversity among the evaluated materials. The two methods of grouping revealed that the MN08, MN09 and MN10 individuals are the most divergent and therefore the most suitable for conservation and breeding programs of the species.