Abstract

The variation of two (humid and semiarid) populations of the honeybee, Apis mellifera L., from western Africa, was analysed, using microsatellite polymorphism of nuclear DNA. One worker was sampled from each of 133 colonies collected from 38 localities in Nigeria, Niger, Cameroon and Chad and analysed for 15 loci. A total of 292 different alleles were recorded for the 15 microsatellite loci. All loci were polymorphic and the number of different alleles per locus ranged between 10, in locus At163, and 31, in locus A029, while allelic frequencies ranged from 0.007 to 0.569. The mean number of different alleles per locus was 19.5 ± S.E 1.1. The unbiased expected heterozygosity was 0.861 ± S.E. 0.017 for the combined populations and 0.859 ± S.E. 0.023 and 0.864 ± S.E. 0.026 for the humid and semiarid populations, respectively. The overall FST value, which is a good estimate of genetic differentiation of populations, was very low: 0.007 ± S.E. 0.001 (0.001 - 0.014) and AMOVA revealed that the two populations were not significantly different from each other (p > 0.05). Similarly, Raymond and Rousset’s exact test of population differentiation revealed that the two populations were not significantly differentiated at p = 0.05. Furthermore a Bayesian assignment test did not produce clear grouping of the populations. In a nutshell, according to microsatellite analysis, the honeybees of the area of study belonged to a genetically undifferentiated population.

Key words: Apis mellifera, honeybee, microsatellites, variation, population, genetic, biodiversity, DNA.