A DNA barcoding approach to characterize pollen collected by honeybees

Area of Science:

• Botany
• Genetics
• Food Science

Background:

• Honeybee pollen is a valuable food supplement with therapeutic properties.
• Understanding pollen composition is crucial for its nutritional and medicinal applications.
• Traditional methods for pollen identification can be time-consuming and lack precision.

Purpose of the Study:

• To evaluate the effectiveness of DNA barcoding for characterizing honeybee pollen pellets.
• To identify the plant species present in pollen collected from an alpine protected area.
• To assess the influence of local biodiversity and environmental factors on pollen composition.

Main Methods:

• Collected pollen pellets from modified beehives in three distinct zones of the Grigna Settentrionale Regional Park, Italy.
• Assembled a DNA barcoding reference database using rbcL and trnH-psbA sequences from 693 plant species.
• Identified pollen samples using the DNA barcoding database, achieving species-level identification for most samples.

Main Results:

• Fifty-two plant species were identified in the honeybee pollen pellets at the molecular level.
• The psbA-trnH marker proved effective for species-level identification, while rbcL alone had limitations with congeneric species.
• Pollen composition varied significantly with elevation, with lower altitudes showing deciduous forest species, including invasive and ornamental plants.

Conclusions:

• DNA barcoding is a powerful tool for accurate honeybee pollen characterization.
• Pollen composition is influenced by local flora, plant phenology, and the presence of alien species.
• Molecular identification can assist beekeepers in producing honeybee products tailored to market demands for specific nutritional or therapeutic benefits.