Genetic variability of umbu trees in Brazilian Semi-Arid region, based on AFLP markers

Abstract

The objective of this work was to evaluate the genetic variability distribution of umbu tree (Spondias tuberosa), within Brazilian Semi-Arid region, based on AFLP markers, in order to suggest prospecting and
preservation strategies for this species. Sixty-eight umbu trees of 15 ecogeographic regions were analyzed for 141 polymorphic AFLP bands, through the UPGMA dendrogram and the multidimensional scaling (MDS),
based on Jaccard’s coeffi cient . Analysis of molecular variance was accomplished by total decomposition among and within ecogeographic regions. The dendrogram presented co-phenetic value of 0.96, while the
MDS presented 0.25 for the badness-of-fi t. Umbu genetic variability was estimated in 0.3138, indicating a large variance among individual groups. Specifi c clusters were observed in six ecogeographic regions, and some individual pairs were observed in the other regions, with no specifi c clustering by sampling place, which indicates that the genetic variability of umbu tree is not uniformly distributed within Brazilian Semi-Arid. Strategies are suggested to set a larger number of protection areas for in situ conservation, or a smaller number of umbu individuals sampled, in various ecoregion units, for ex situ genetic variability conservation of this species.