D3091: Transmission dynamics of honey bee associated viruses in flowers, pollen, and honeybees (Apis mellifera) during the pollination of California almonds

California is responsible for 80% of global almond exports and is dependent on the pollination services of the Western honeybee, Apis mellifera. This requires 60% of U.S. commercial migratory honeybees to facilitate pollination. Increased population densities coupled with stress factors such as pathogen exposure pose a risk for vial spread to honeybees throughout their migratory visits to almonds and subsequent crops. Viruses such as Deformed Wing Virus (DWV) are of major concern for colony loss and colony collapse disorder in domesticated honeybees. 

Flowering plants and pollen also play a role in the dispersal of honeybee disease. Flowers act as dirty door knobs “reservoirs” for infected bees to spread pathogens to noninfected individuals through pollination. Pollen may serve as a vector for viruses to spread to plants and honeybee hosts alike. Of 1500 known plant viruses, 75 have been deemed pollen-associated, such as Prunus Necrotic Ringspot Virus (PNRV) which has been shown to spread via bee pollination. Pollen can also harbor honeybee RNA viruses such as (DWV) and Back queen cell virus (BQCV). 

Viral jumps mediated by pollen between plant and pollinator hosts are poorly understood. My study aims to identify honeybee viruses associated with pollen in the economically important almond crop in California. I aim to understand vectoring dynamics between honeybees, almond flowers, and pollen throughout the seasonal bloom. Broadly, this study aims to advance our understanding of disease transmission dynamics in migratory honeybee operations, with the potential to create better practices for disease control.