Culturable yeast community associated with grape must and honey bees sampled from apiaries located in the vineyards

In this study, we investigated culturable yeast community, present in grape must sampled from vineyards with apiaries on the borders, and in honey bees collected in these apiaries.

To this aim, yeasts isolated from spontaneously fermented grapes randomly collected in two vineyards (P1 and P2) with apiaries on the borders (A1 and A2) were compared to those isolated from spontaneously fermented grapes collected from a vineyard without apiary (P4). At the same time, yeast community was analyzed on bees collected in each apiary placed in the vineyards, in comparison to yeasts isolated from an apiary (A3) located far from the vineyards. The analysis was performed for two consecutive years (2021 and 2022). The isolated yeasts were identified by restriction analysis of amplified ITS region, followed by sequencing of ITS fragment.Our research showed that the presence of apiaries seems to increase yeast counts of grape must, in particular of Saccharomyces cerevisiae; furthermore, the permanence of apiaries in the vineyards allowed the recovering of these yeasts also from bees.

Our findings seem to corroborate the role of bees as vectors and reservoirs of oenologically relevant yeasts, such as a source of non-conventional yeasts with potential biotechnological applications.