Genetic Structure of the Africanized Apis Mellifera L. in a River Valley in the Semi-Arid Region of Brazil

The effect of the basin of the Gurgueia River (perennial river in the semiarid region of Brazil) on the dispersion and migration of Africanized bees (Apis mellifera) was evaluated using six microsatellite markers. Four municipalities located within (n = 53 colonies) and three outside the Gurgueia River Basin (n = 41 colonies) were sampled. Based on the number of alleles found (mean of 18.5 alleles per locus +/- 4.18), we concluded that there was high genetic diversity. Estimates of population differentiation (F-ST) were significant among different localities, except for the populations of Corrente, Cristino Castro, and Bertolinia, which are within the river basin. At a regional level, analysis of molecular variance (AMOVA) and Bayesian approaches corroborated this result, indicating greater connectivity among populations in the valley. For the remaining populations collected outside the valley, no defined pattern of population structure was observed.