Grant: Discovery Grants Program - Individual

Honey bees are arguably the most significant pollinators of agricultural crops: They provide reliable pollination services that increase the efficiency of food production, contributing up to $39.5 billion to the Canadian and U.S. economies. However, it is becoming more difficult and costly for beekeepers to maintain healthy, productive colonies, and overwintering losses have been unsustainably high. Survey results show that beekeepers cite `poor queens' as one of the primary causes of colony mortality, yet little is known about what is causing this decline in queen quality. Each colony is headed by a single queen, and as the sole egg-layer and mother to all the bees in her colony, any factor impacting her health also affects the entire hive. Unfortunately, about half of queens need to be replaced within their first six months of heading a colony, despite having potential lifespans upwards of three years, which equates to a huge loss of potential productivity. Evidence is mounting that queens are vulnerable to viral and fungal infections, which could have serious consequences for their fertility and therefore colony productivity. In our research, we plan to investigate how pathogenic infections alter queen physiology and how they may compromise queen fertility. We will use a combination of detailed laboratory trials and realistic, isolated field trials to determine short- and long-term effects of infection, coupled with our world-leading, in-house proteomics technology to discover mechanisms of pathogenicity that impact reproduction. Queen fertility is affected not only by her ability to produce eggs, but also her capacity to fertilize them. A young queen embarks on several nuptial flights and stores her mates' sperm in a specialized organ, the spermatheca, which she uses to fertilize eggs for the rest of her life. The queen's ability to keep sperm alive has economic consequences: Poor queens have a higher proportion of dead sperm within their spermatheca than healthy queens, but we have a poor understanding of what causes this sperm death. We aim to develop an artificial sperm storage system to facilitate studying molecular mechanisms underlying sperm viability and longevity. Once we have established this system, we will use it to, for example, adjust enzyme activities with inhibitors, add metabolites, or pull out proteins, then observe effects on sperm quality. Our targets will be informed in part by investigating what proteins are linked to sperm viability in other social insect species, and in part by observing what processes are disrupted by pathogenic infections. Our vision is to bolster the beekeeping industry by improving queen quality and, by extension, the productivity and health of their colonies. If we can understand why queens are failing prematurely, we can establish best management practices to help beekeepers mitigate those risks, and advance toward our long-term objective of sustaining and securing honey bee health.