Genetic Characterization of Commercial Honey Bee (Hymenoptera: Apidae) Populations in the United States by Using Mitochondrial and Microsatellite Markers

Abstract

Genetic diversity levels within and between the two commercial breeding areas in the United States were analyzed using the DraI restriction fragment length polymorphism of the COI-COII mitochondrial region and 10 polymorphic microsatellite loci. The western commercial breeding population (WCBP) and the southeastern commercial breeding population (SCBP) were sampled in 1993–1994 and again in 2004–2005. The goal of this study was to characterize the genetic composition of these populations and to measure potential changes in genetic diversity and composition across the sampling period. The mitochondrial DNA haplotypes C1 and C2, characteristic of the most popular bee strains (Italians and Carniolans, respectively) sold in the United States, were the dominant haplotypes at both sample dates. The frequency of Apis mellifera mellifera M haplotypes, M4, M7, and M7′, decreased during the 10-yr span. An A1 haplotype characteristic of Africanized bees was found in the SCBP from 2005. Microsatellite analysis showed there was a loss of alleles in both the WCBP and SCBP, but the losses were not significant due to simultaneous gains of new alleles into these populations between 1993 and 2005. Genetic differences that occurred between the 1993–1994 WCBP and SCBP were still detectable in these populations sampled a decade later, suggesting that these populations could be useful sources of diversity for each other in the future.

Genetic Variability of Stingless Bees Melipona mondury Smith and Melipona quadrifasciata Lepeletier (Hymenoptera: Apidae) from a Meliponary

“…Another explanation to account for the low variability may be related to the artificial maintenance of hives through founder events and bottlenecks as already reported for Apis mellifera (Sheppard, 1988;Schiff & Sheppard, 1996;Moritz et al, 2007;Delaney et al, 2009;Jaffé et al, 2010;Meixner et al, 2010) and M. scutellaris (Carvalho-Zilse et al, 2009;Alves et al, 2011). However, despite low variability, populations can be successfully maintained if a strong care is dispensed over the nests .…”

Genetic characterization of the honeybee (Apis mellifera) population of Rodrigues Island, based on microsatellite and mitochondrial DNA

“…Presence of European C lineage haplotypes is consistent with the reported introduction of queens bought from the US commercial stock (Bappoo and Ramanah 1989). In the USA, haplotypes C1 and C2 are characteristic of the most popular honeybee strains sold (Delaney et al 2009). These commercially widespread subspecies have adapted well to the environmental conditions of this tropical island and persisted for over 32 years.…”

“…For four comparable loci (A113, Ap55, B124, and Ap43), indigenous populations of A. m. carnica and/or ligustica in Croatia and Italy showed between 9.25 and 9.75 alleles per locus whereas 8.50 alleles were detected in the Rodrigues population (Muñoz et al 2009). Another indication of the high levels of genetic diversity was heterozygosity (H obs =0.644) which was equivalent to (i) indigenous Italian and Croatian populations (H obs =0.638 and H obs =0.674, respectively (Muñoz et al 2009)) and (ii) US commercial populations (H obs =0.53 in 2005 (Delaney et al 2009)). Levels of heterozygosity of the Rodrigues honeybee population were higher than other insular systems in which A. m. ligustica was introduced.…”

“…The breakdown of the different evolutionary lineages is supported by molecular analyses (Garnery et al 1992;Whitfield et al 2006;Wallberg et al 2014). The European subspecies Apis mellifera ligustica and Apis mellifera carnica (C lineage) have been introduced worldwide because of their commercially desirable traits and have succeeded in adapting to new habitats (Chapman et al 2008;Delaney et al 2009). …”

Honey Bees (Apis mellifera L.) and Pollination Issues: Current status, impacts and potential drivers of decline

“…The genetic variability of the US honey bee population is reduced compared to that of indigenous honey bee populations of Europe (Sheppard, 1988). In addition, it has been reported that as few as 500 breeder queens have been used to provide progeny for most of the commercial hives present in the US (Schiff & Sheppard, 1995;Delaney, Meixner, Schiff, & Sheppard, 2009). Lack of genetic diversity may be responsible for colony losses as the genetic similarity among colonies in wide areas increases the chances of successful disease transmission.…”