Bursera simplex Rzed. & Calderón fruits and seeds in different sites and tree structure

Abstract

The territory of Oaxaca State has the greatest biodiversity in Mexico; the most abundant vegetation is the low deciduous forest with Bursera species of economic and biological importance. In the present study, the structural composition and phenotype of Bursera simplex seed trees and the characteristics of the site in which they grow were evaluated; their production of fruits and seeds were described according to the tree from which they were harvested. During 2015, a sampling of 23 sample units was conducted towards the best phenotypes with high production of fruits and seeds and their inventory was made. The data were analyzed through structural indexes and analysis of variance to compare the production of fruits and seeds, in relation to the tree from which they were taken, as well as the characteristics of the site, altitude, slope and position of the place where the specimens grew. Those of greater size are associated with slopes ≤ 25 % and altitudes ≤ 1 278 m, where they produce 29 259 seeds kg^-1. The population structure is of irregular type, with important densities of Bursera simplex associated with the western exposure; the forest value index, the importance value index and the complexity index affect the morphological characteristics of fruits and seeds.