Diversidade genética em castanheira-do-gurgueia (Dipteryx lacunifera Ducke) com base em características físicas e químico-nutricionais do fruto

this study aimed to evaluate the genetic divergence among 23 "castanheira-do-gurguéia" genotypes based on fruit physical, chemical and nutritional characteristics. fruits were collected from natural occurrence areas of the piauí southwestern savannah. the physical characteristics analyzed were: (a) fruit - average mass (mmf), length (cf), width (lf), thickness (ef) and pericarp average mass (mmp); and (b) nut - average mass (mmc); length (cc), width (lc) and thickness (ec). the nut chemical and nutritional characteristics analyzed were: fat, crude protein, crude fiber, ash and total carbohydrates, all expressed in percentage; crude energy, expressed in kcal 100 g-1, and the minerals (p, k, ca, mg, mn, fe, cu and zn), expressed in mg 100 g-1. the genetic divergence was evaluated using mahalanobis distance as dissimilarity measure and evaluated the relative importance of the characteristics in the genetic divergence. tocher and upgma grouping methods were used. a high variability for these characteristics was observed among genotypes. the genotypes g-17 and g-18 are the most divergent and the genotypes g-3 and g-16 are the most similar. the characteristics that had the greater contributions to the genetic divergence among genotypes were mmp, mmf, e, fb, ct and pb. the "castanha-do-gurguéia" is richer in p, k, mg, pb, fb, ct and e.