Pollen DNA metabarcoding approach to profile the nectar source for urban beekeeping in Tokyo Bay Area, Koto-ku. honey metagenome

Apis mellifera are a honey bee that introduced around the world as industrial beekeeping species. Recently, urban beekeeping has attracted attention for the purpose of ecosystem protection and urban greening. This study investigated to understand nectar sources by pollen DNA metabarcoding though urban beekeeping in Koto-ku, Tokyo. The Musashino university beekeeping using honey bee, A. mellifera, was carried out on the roof of the second building at Musashino University Ariake Campus in the Ariake district of Koto-ku on the Tokyo Bay coast. The honey containing pollen was sampled from a relatively new hive that divided into three periods of early, middle and late months between mid-March, 2018 to mid-October, 2018. After adding water to reduce viscosity of honey, whole liquid phase was grinded with beads. Genomic DNA was extracted using an MPure Bacterial DNA Extraction Kit. The extracted DNA solution was mixed with a final concentration of 5% PVPP and purified by collecting the supernatant after centrifugation. An amplicon library targeting a part of rbcL region in chloroplast genome was constructed by 2-step tailed PCR approach. A mixture of multiple libraries was sequenced by 2 x 300 bp paired-end reads using a MiSeq platform. A total of 32 spots could be sampled except early July. In early-May, early-, mid-, and late-June, mid-July, early- and mid-August, mid-September, and early-October, samples were taken from multiple hives. Sequence data of 6,994-95,832 paired-end reads were output for each sample.