Management tools for genetic diversity in an isolated population of the honeybee (Apis mellifera) in New Zealand

Abstract

Context Beekeepers and honeybee queen breeders alike currently have few tools at their disposal for the management of genetic diversity inside their populations. Pedigree information is often absent, beekeepers cannot afford to genotype selection candidates due to costs, and acquisition of material for genotyping without risk to individual queen bees is difficult. However, in New World honeybee populations where import of additional genetic material to refresh the population is restricted (e.g. Australia) or impossible (e.g. New Zealand), management of genetic diversity is important for population sustainability. While the role of individual beekeepers in maintaining genetic resources becomes crucial under these circumstances, a more holistic approach to the management of genetic diversity is needed to allow for maximum impact of their contribution. Aims The establishment of affordable genotyping methodologies for successful strategies in managing honeybee genetic diversity, as well as the necessary delivery systems for the results to support the beekeeping community by providing interpretation in the context of the wider population. Methods Genotyping-by-sequencing of honeybee samples collected as part of a national survey were used as the basis for assessment of New Zealand’s honeybee genetic diversity and development of a tool with largely self-explanatory outputs that can be used directly by beekeepers. Key results It would appear that New Zealand’s honeybee population is sufficiently diverse to maintain population viability. However, both within regions and within companies, genetic diversity is significantly reduced, especially in the case of specialised queen breeders, indicating that active management will be necessary to achieve long-term sustainability. Conclusions Interactive tools are needed to help beekeepers understand their role in maintaining overall genetic diversity in the honeybee population as well as the potential impact of planned bee movement and queen acquisitions. Regular rounds of voluntary bee sampling can be used as the basis for management decisions without concentrating genotyping load on specific operators and restricting diversity assessments to subpopulations. Implications The described strategy is expected to both improve the outlook of New Zealand’s honeybee population as a whole and facilitate stringent genetic improvement programs by enabling queen breeders to make informed selection decisions and giving beekeepers confidence in the viability of their population.