To determine whether genotype spacial distribution is random or structured, spacial genotypic autocorrelation was used to compare two natural populations of Myracrodruon urundeuva in the semi-arid region of Northeastern Brazil (Estação Ecológica do Seridó/RN - 1166,38/ha and Sítio Mata dos Alves/PB - 84/ha). The former is characteristic of preserved areas, while the latter is found in areas with marked anthropogenic degradation. The program "Autocorr" was used for the analysis. The autocorrelation was run on polymorphic loci detected in the adult individuals. Two alleles were analyzed at the Estação Ecológica do Seridó and 4 at the Sítio Mata dos Alves. The three methods used for analysis were: Connection of Gabriel (Ig), Closest neighbor (Ivmp) and Pre-established distance comparisons. The results obtained for Ig and Ivmp (Pgm2: 0,032 and 0,236; Est-1: 0,263 and 0,242, respectively) in the ecological station sample/populations and Ig and Ivmp (Pgm-1: -0,349 and -0,288; Pgm-2: -0,341 and 0,278; Est-1: -0,349 and -0,284 and Mdh-1: -0,345 and -0,282, respectively) in the farm sample/populations. The results did not indicate the presence of special genetic structure, making it possible to hypothesize that there is an internal randomized genotypic distribution of the genotype. The same was detected for the pre established distance comparisons. The results maintained the same pattern found in some natural populations of tropical tree species studied.
Myracrodruon urundeuva; natural populations; semi-arid; genotypes, alleles, and autocorrelation
