Modern methods of assessing the taxonomic affiliation of honeybee colonies

Diversity and Evolution of pogo and Tc1/mariner Transposons in the Apoidea Genomes

Bees (Apoidea), the largest and most crucial radiation of pollinators, play a vital role in the ecosystem balance. Transposons are widely distributed in nature and are important drivers of species diversity. However, transposons are rarely reported in important pollinators such as bees. Here, we surveyed 37 bee genomesin Apoidea, annotated the pogo and Tc1/mariner transposons in the genome of each species, and performed a phylogenetic analysis and determined their overall distribution. The pogo and Tc1/mariner families showed high diversity and low abundance in the 37 species, and their proportion was significantly higher in solitary bees than in social bees. DD34D/mariner was found to be distributed in almost all species and was found in Apis mellifera, Apis mellifera carnica, Apis mellifera caucasia, and Apis mellifera mellifera, and Euglossa dilemma may still be active. Using horizontal transfer analysis, we found that DD29-30D/Tigger may have experienced horizontal transfer (HT) events. The current study displayed the evolution profiles (including diversity, activity, and abundance) of the pogo and Tc1/mariner transposons across 37 species of Apoidea. Our data revealed their contributions to the genomic variations across these species and facilitated in understanding of the genome evolution of this lineage.

Beekeeping Genetic Resources and Retrieval of Honey Bee Apis mellifera L. Stock in the Russian Federation: A Review

The loss of honey bees has drawn a large amount of attention in various countries. Therefore, the development of efficient methods for recovering honey bee populations has been a priority for beekeepers. Here we present an extended literature review and report on personal communications relating to the characterization of the local and bred stock of honey bees in the Russian Federation. New types have been bred from local colonies (A. mellifera L., A. m. carpatica Avet., A. m. caucasia Gorb.). The main selection traits consist of a strong ability for overwintering, disease resistance and different aptitudes for nectar collection in low and high blooming seasons. These honey bees were certified by several methods: behavioral, morphometric and genetic analysis. We illustrate the practical experience of scientists, beekeepers and breeders in breeding A. mellifera Far East honey bees with Varroa and tracheal mite resistance, which were the initial reasons for breeding the A. mellifera Far Eastern breed by Russian breeders, Russian honey bee in America, the hybrid honey bee in Canada by American breeders, and in China by Chinese beekeepers. The recent achievements of Russian beekeepers may lead to the recovery of beekeeping areas suffering from crossbreeding and losses of honey bee colonies.

Estimation of C-derived introgression into A. m. mellifera colonies in the Russian Urals using microsatellite genotyping

BACKGROUND

Marker-assisted selection is well established in animal breeding method of selecting individuals with desirable traits in a breeding scheme based on DNA molecular marker patterns.

OBJECTIVE

Genetic diversity and C-derived admixture into local purebred gene pool of A. m. mellifera colonies was assessed using polymorphism of nine microsatellite loci in order to provide further marker-assisted selection of desired honey bee colonies.

METHODS

The genetic diversity and the level of C-derived introgression into A. m. mellifera colonies in the Shulgan-Tash Nature Reserve (Russia) was assessed based on nine microsatellite loci (ap243, 4a110, A24, A8, A43, A113, A88, Ap049, A28), which were analized using the fragment analysis of the PCR products in Applied Biosystems 3130 DNA Analyzer. Phylogenetic relationship of colonies was evaluated using Neighbor-Joining methods with Cavalli-Sforza and Edwards genetic distance using the PHYLIP 3.68. The model-based Bayesian clustering algorithm implemented in STRUCTURE 2.3.3 was employed to infer membership and introgression proportions (Q-value).

RESULTS

In the Shulgan-Tash Nature Reserve colonies of A. m. mellifera subdivided into four groups by level of C-derived introgression. Only five colonies of A. m. mellifera had C-derived introgression which varied from 0.5 to 2%. The genetic diversity in colonies of A. m. mellifera varied from 0.12 to 0.40. The Neighbor-Joining tree demonstrates the genetic relationship of A. m. mellifera colonies, which subdivided into three groups with different levels of C-derived introgression. Group 1 combined five honey bee colonies Bort_1, Bort_2, Bort_3, Baisalyan_1, and Kush_7 with a fraction of introgression close to 0.000 and genetic diversity from 0.20 to 0.25.

CONCLUSION

The results showed the excellence of nine microsatellite loci genotyping in estimation of genetic diversity, distinguishing the two European evolutionary lineages M and C and estimating C-derived introgression. These genetic parameters can be applied further to perform the marker-assisted selection of purebred dark European honey bees.