Pollen DNA metabarcoding identifies regional provenance and high plant diversity in Australian honey

Dr Liz Milla¹, Dr Kale Sniderman², Dr Rose Lines³, Dr Mahsa Mousavi-Derazmahalleh³, Dr Francisco Encinas-Viso¹

¹Centre for Australian National Biodiversity Research, CSIRO, , Australia, ²School of Earth Sciences, The University of Melbourne, , Australia, ³eDNA frontiers Laboratory, Curtin University, , Australia

Abstract:

Accurate identification of the botanical components of honey can be used to establish its geographical provenance, while also providing insights into honey bee (Apis mellifera L.) diet and foraging preferences. We used pollen DNA metabarcoding to identify the floral resources and foraging preferences of honey bees using 15 honey samples from six bioregions from eastern and western Australia. We used two plant metabarcoding markers, ITS2 and the trnL P6 loop, which combined identified a total of 55 plant families, 67 genera and 43 species. The trnL P6 loop marker provided significantly higher detection of taxa, detecting an average of 15.6 taxa per sample, compared to 4.6 with ITS2. Most honeys were dominated by Eucalyptus and other Myrtaceae species, with a few honeys dominated by Macadamia (Proteaceae) and Fabaceae. Metabarcoding detected the nominal primary source provided by beekeepers amongst the top five most abundant taxa for 85% of samples. Eastern and western honeys could be clearly differentiated by their floral composition, and clustered into bioregions with the trnL marker. Comparison with melissopalynology analysis shows that metabarcoding can detect similar numbers of plant families and genera, but provides significantly higher resolution at species level. Our results show that pollen DNA metabarcoding is a powerful and robust method for detecting honey provenance and examining the diet of honey bees. This is particularly relevant for hives foraging on the unique and diverse flora of the Australian continent, with the potential to be used as a novel monitoring tool for honey bee floral resources.

Biography:

Biographies to come