Abstract Description

Honeybees are integral to agricultural as pollinators and contribute to global biodiversity and ecosystem stability. However, honeybee populations face significant declines due to multiple stressors. In recent years, the honeybee microbiome has emerged as critical in host health, immunity, and resilience. In this study the dual role of the honeybee mycobiome as both a reservoir for beneficial fungi and a vector for fungal plant pathogens was investigated. Previous studies showed that fungal pathogens can be detected on the surfaces of bees, and in pollen and honey, indicating a potential transmission and introduction of plant pathogens into crops. In this study Cladosporium cladosporioides and Botrytis cinerea were found on bees and within hives in blueberry orchards. Feeding studies suggest that spores from both fungal species influenced honeybee foraging behaviour, most likely due to some nutrient benefit as honeybees are attracted to phenolics and volatile organic compounds (VOCs) and can discern differences in amino and fatty acids. Physiological assays showed differential effects of fungal-supplemented pollen on bee gene expression and highlight the intricate balance between nutritional quality and immune function. Understanding the evolutionary and ecological dynamics of bee-fungus interactions is therefore essential for developing effective management strategies.