UNDERSTANDING HONEY BEE MICROBIOTA TO IMPROVE BEE NUTRITION AND COLONY HEALTH

Increasing evidence points to a core honey bee gut microbiota, however the distribution and function of peripheral bacterial and fungal communities in honeybees and their food stores are relatively unknown. Our work will focus on bee bread to define the contribution of unknown and seemingly benign microbes to colony health and nutrition. Bee bread provides the bulk of proteins, vitamins and lipids that bees consume. We will determine the microbial succession in bee bread to understand the distribution of these bee bread-associated microbial communities and whether these communities contribute to the nutritive value of pollen, its digestion and storage, and the potential for disease transmission and amplification. We will examine factors associated with beekeeping and agricultural practices that may affect the microbial balance of the honey bee and its stored food, including colony origin, supplemental feeding, nectar source, pollen type, and exposure to biocides. These data will inform our perspective on how microbial communities contribute to colony health. OBJECTIVES Our overall goal is to provide beekeepers and growers with practical advice for the maintenance of transitory commercial honey bee populations. Using a combination of laboratory and field approaches we will develop an understanding of the diversity, abundance, persistence and functional capacities of the microorganisms that occur in bees, stored food, the hive, and the general pollination environment. This information will be applied to the management of disease, nutrition, overwintering and biocides in the context of commercial beekeeping. Objective 1: Determine the core fungal microbiota in bee bread and determine relationships with bacterial communities. Subobjective 1A: Enumerate, identify, and characterize the core fungal and bacterial microbiota of bee bread. Objective 2: Characterize microbial succession in bee bread, including core and non- core microbes and their persistence during overwinter pollen storage. Subobjective 2A: Identify the microbial communities involved in the conversion of corbicular pollen to bee bread. Subobjective 2B: Determine the impact of overwintering on the microbes in bee bread. Objective 3: Identify factors affecting a colony's microbial diversity, including plant monocultures, exposure to biocides, and supplemental feeding. Subobjective 3A: Determine the effect of supplemental feeding on microbial communities. Subobjective 3B: Determine the effect of monoculture nectar and pollen source on microbial communities. Subobjective 3C: Determine the effect of fungicides on microbes during bee bread formation.