The diversity and spatial genetic distribution of Myracrodruon urundeuva genotypes were studied in two Brazilian populations in the Southwest (Selvíria-SEL) and Southeast Brazilian regions (Paulo de Faria-PFA). Twenty-five and thirty adult individuals were evaluated for five allozyme systems in SEL and PFA populations, respectively. Estimates of the genetic divergence between populations were low (=0.043). Observed and expected heterozygosities were high in both populations (0.317 to 0.511, respectively). Significant and excessive number of heterozygotes was detected in PFA population (=-0.252). The spatial distribution analysis through Moran's index I revealed a significant structuring up to 5,224 m in the more exploited population (SEL, =0.09) and a trend to randomness in the less exploited area (PFA, = -0,02). Seed dispersion near mother trees and the recolonization process through seeds from few genotypes are probable causes of the structuring in the SEL population. The implications of the results are discussed from the conservation and breeding point of views.
Forest tree species; I Moran index; genetic diversity; allozymes
