Genetic diversity and population structure of two subspecies of western honey bees (Apis melliferaL.) in the Republic of South Africa as revealed by microsatellite genotyping

Abstract

Apis mellifera scutellata and Apis mellifera capensis, two native subspecies of western honey bees in the Republic of South Africa (RSA), are important to beekeepers in their native region because beekeepers use these bees for honey production and pollination purposes. Additionally, both bees are important invasive pests outside of their native ranges. Recently, whole mitogenome sequencing and single nucleotide polymorphisms were used to study their genetic diversity. To add to our knowledge of the molecular ecology of both bees, we tested the ability of microsatellites to be used as a tool to discriminate between A.m. capensis and A.m. scutellata. We analyzed the genetic variability and overall population structure of both bee subspecies and hybrids of the two by genotyping individuals collected from RSA (N = 813 bees from 75 apiaries) at 19 microsatellite DNA loci. Overall, populations averaged between 9.2 and 11.3 alleles per locus, with unbiased heterozygosity values ranging from 0.81 to 0.86 per population. Bayesian clustering analyses revealed two distinct evolutionary units, though the results did not match those of earlier morphometric and molecular analyses. This suggests that the microsatellites we tested were not sufficient for subspecies identification purposes, especially for Cape and hybrid bees. Nevertheless, the microsatellite data highlight the considerable genetic diversity within both populations and a larger-than-expected hybridization zone between the natural distributions of A.m. capensis and A.m. scutellata.

Attack of the dark clones the genetics of reproductive and color traits of South African honey bees (Apis mellifera spp.)

“…m . capensis and 158 were hybrids of the two subspecies [ 18 , 26 , 53 , 54 ]. Phenotyping methods as described in [ 19 ] determined morphometric phenotypes that significantly differed between the two subspecies of honey bees.…”

“…Location data for the samples, including GIS coordinates, can be found in S1 File. Combined morphometrics, SNP, microsatellite and mitochondrial DNA data were used to determine that 73 bees were A.m. scutellata, 234 were A.m. capensis and 158 were hybrids of the two subspecies [18,26,53,54]. Phenotyping methods as described in [19] determined morphometric phenotypes that significantly differed between the two subspecies of honey bees.…”

The Movement of Western Honey Bees (Apis mellifera L.) Among U.S. States and Territories: History, Benefits, Risks, and Mitigation Strategies

“…There are also techniques for screening for unwanted species/subspecies of honey bees, though they vary in degree of accuracy. For example, the African honey bee, A. m. scutellata, and its hybrids can be identified using a reduced set of single nucleotide polymorphisms (SNPs), a real-time qPCR assay, or combinations of morphological features (Pinto et al, 2014;Harpur et al, 2015;Munoz et al, 2015;Eimanifar et al, 2018Eimanifar et al, , 2020Boardman et al, 2021;Momeni et al, 2021). Geo-morphometric analyses of honey bee wings coupled with SNP data (Calfee et al, 2020;Henriques et al, 2020), or geo-morphometrics alone (Nawrocka et al, 2018;Bustamante et al, 2020) have been used to identify A. m. scutellata populations as well.…”

Further Evidence of Population Admixture in the Serbian Honey Bee Population

“…It is noted that in areas that are natural contact zones of different A. mellifera subspecies, natural hybridization occurs [40,41] and the hybridization is inevitable in regions where human interference due to beekeeper preferences is high, which occurred in the C lineage native area of distribution [24][25][26]42,43]. Serbia, located in the center of the Balkan Peninsula, is geographically in the middle of the distribution range of the C lineage.…”