Abstract
Accurate identification of the botanical components of honey can be used to establish its geographical provenance, while also providing insights into honeybee (Apis mellifera L.) diet and foraging preferences. DNA metabarcoding has been demonstrated as a robust method to identify plant species from pollen and pollen‐based products, including honey. We investigated the use of pollen metabarcoding to identify the floral sources and local foraging preferences of honeybees using 15 honey samples from six bioregions from eastern and western Australia. We used two plant metabarcoding markers, ITS2 and the trnL P6 loop. Both markers 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 among the top five most abundant taxa for 85% of samples. We found that eastern and western honeys could be clearly differentiated by their floral composition, and clustered into bioregions with the trnL marker. Comparison with previous results obtained from melissopalynology 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 honeybees. 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 honeybee floral resources.
Highlights
European honeybees (Apis mellifera L.) are one of the most important pollinators of crops worldwide (Calderone, 2012; Potts et al, 2010), as well as the principal producers of commercial honey and pollen products (Pascoal et al, 2014)
While the total numbers of identified taxa differed greatly, we found a high overlap between the number of families detected by both internal transcribed region 2 (ITS2) and transfer RNA gene for Leucine (trnL)
We found the majority of genera detected in samples from a given region matched to genera found in the corresponding Interim Biogeographical Regionalisation for Australia (IBRA) list (BBS: 74%, MUL: 75%, NAN: 100%, New England Tablelands (NET): 83%, South East Queensland (SEQ): 86%, and Swan Coastal Plain (SWA): 79%)
Summary
European honeybees (Apis mellifera L.) are one of the most important pollinators of crops worldwide (Calderone, 2012; Potts et al, 2010), as well as the principal producers of commercial honey and pollen products (Pascoal et al, 2014). Pollen DNA metabarcoding, a molecular method for pollen identification, has been used several times to investigate foraging by bees (Cornman et al, 2015; Galimberti et al, 2014; Nürnberger et al, 2019; Richardson, Lin, Quijia, et al, 2015; de Vere et al, 2017; Wilson et al, 2010) and to establish the floral content and geographical provenance of honey (Bruni et al, 2015; Hawkins et al, 2015; Utzeri et al, 2018). We examine whether pollen found in honey reflects the flora from its IBRA region of origin, and determine the usefulness of pollen metabarcoding in discriminating between bioregions, and in detecting plant species from a particular locality
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
