AW: Wirkungen von Pestiziden auf das Mikrobiom des Bien
P2.60 BRIAN Z. HEDGES1, DAVID M. KOLAKOWSKI1, JAY A. YODER1, DIANA SAMMATARO2 AND GLORIA DeGRANDI-HOFFMAN2. Wittenberg University1, USDA-ARS, Carl Hayden Honey Bee Research Center2. Alteration of honey bee (Apis mellifera) colony nutritional source, "bee bread", in response to fungicide exposure.
Symbiotic bee colony fungi convert stored pollen into bee bread, satisfying an absolute dietary requirement for developing bee larvae. When sprayed, fungicides are brought into the colony by bees via contaminated pollen. This study explores effects of fungicide on bee bread fungi in vitro by radial growth rate determination of 12 bee bread fungal isolates with Pristine® (BASF), a broad spectrum fungicide frequently applied to various commercial crops. Natural comb cell conditions were simulated by conducting the experiment on bee-bread supplemented non-nutritive agar, 30oC, darkness, and 5% CO2. Radial growth rates for each fungus were characteristic and were reduced 12% - 80% by fungicide, depending on species and concentration, in a dose-response. Percentage reduction in growth rates, mortality, and least effective concentration differed among the 12 fungi and did not correlate with whether the fungus was a slow/moderate- or fast-grower; i.e., no two fungi responded the same. Effectiveness of Pristine is species (likely strain)-specific and is not a function of slow growth retaining fungi on treated surfaces longer or decreased exposure times by faster growers that spread rapidly. Most tolerant fungi to Pristine were Rhizopus sp., Mucor sp., and Absidia sp., and Penicillium sp. and Aspergillus niger were the most sensitive. Pristine had a controlling effect on bee fungal pathogens, Ascosphaera apis (chalkbrood) and Aspergillus flavus (stonebrood). Thus, bee bread fungi respond to fungicide differently and could have a negative effect on colony health by altering the composition of mycoflora that bees use to process and store their food.
Dem Bien folgen, heißt, den richtigen Weg wählen.