Partial seasonal isolation of African and European-derived Apis mellifera (Hymenoptera : Apidae) Drones at congregation areas from subtropical Mexico

The genetic interactions between European and African-derived honey bees in the Neotropics are unclear. To study the abundance of males of each type, two apiaries with colonies of African-derived honey bee and European honey bee origin were established in the surroundings of one drone congregation area. The frequencies of African-derived honey bee and European honey bee males in the mating area were studied by taking samples of drones at the drone congregation area twice a month for 5 mo, Drones from each type of colony were identified by the use of two allozyme polymorphic systems: malate dehydrogenase (Mdh), hexokinase (Hk), and by haplotype using the EcoRI site of the mitochondrial DNA. The results of a Fisher exact test showed that, although Mdh alleles had similar frequencies across the time of study (P = 0.095), the frequency of Hk alleles and haplotypes in drones varied between months (P = 0.0001). Early in March, the frequencies of African-derived honey bee-typical alleles were significantly higher compared with European honey bee-typical alleles. However, at the end of the season of drone production in July, European honey bee-typical alleles were significantly more frequent in drones than those of the African-derived honey bee type. The results mirror the findings of an early peak of drone brood production reported for African-derived honey bee colonies compared with a peak later in the year in European honey bee ones. It is concluded that the seasonal frequencies of African-derived honey bee and European honey bee drones in the mating areas are not static. They vary in accordance with the different peaks of male production in their respective colonies. This behavior may act as a partial genetic barrier between bee types. The implications of these findings with respect to current levels of Africanization in this region of Mexico and for queen rearing in Africanized areas are discussed.