Pollen characterization of honey from Apis mellifera ruttneri and Apis mellifera buckfast : a case study from Malta

Abstract

Melissopalynology is an important field of study that focuses on the evaluation of pollen found in honey. Since these grains vary in structure, this method of analysis can trace back to which vegetation they belong to, ultimately shedding light on the foraging trends or plant preferences of the honeybees (Apis mellifera). Despite its importance, limited literature exists on the Maltese islands regarding which vegetation is preferred by the endemic honeybee, Apis mellifera ruttneri, leading to an absence of conservancy. The constant hybridisation and importation of other honeybees, such as Apis mellifera buckfast, have also accelerated its endangerment status. This study has found the similarities and lack thereof between the foraging preferences of the two Apis mellifera subspecies residing in Wardija, by analysing 18 honey samples. A standard extraction procedure was used to prepare the samples for microscope analysis for the purpose of pollen identification and quantification. Following this, the pollen was then characterised using cluster analysis. It was found that the subspecies foraged on similar floral families, namely Fabaceae and Asteraceae, but differ at the vegetation-type level. The ruttneri honeybees showed a preference for Hedysarum-type flora while the buckfast had high counts of Vicia sativa and Lotus-type flora, and overall had a higher number of pollen grains in their honey. The latter subspecies showed a lot more clustering than the endemic kind, suggesting that their overall flora selection was not as varied. This research has only provided pollen trends found in honey obtained from one area during one season, therefore further studies would need to be conducted to confirm these findings.