Honey bee queen’s response to nutritional stress may depend on the stock variety

Abstract

There are several honey bee (Apis mellifera) stocks with desirable traits that have been developed through selective breeding, but there are likely to be resultant trade-offs due to biological constraints or neutral evolution. The Russian honey bee (RHB) stock has higher resistance to Varroa mites (Varroa destructor) and tends to have more frequent brood rearing breaks relative to the common Italian honey bee (IHB) stock, which requires high levels of food consumption to sustain long brood rearing cycles. Here, we investigate how queens from the two stocks perform following prolonged nutritional stress in the form of chronic pollen deprivation and a 3-week recovery period. Overall, we find that IHB queens are heavier regardless of their nutritional treatment and that those that did not experience pollen dearth lay more eggs with a higher protein to egg weight ratio. While we cannot rule out the influence of external factors present in the colony setting such as pathogens, our findings suggest that IHB queen egg laying performance may be relatively higher when pollen resources are abundant, but at the same time, they have a higher level of sensitivity to nutritional stress. In addition, our results suggest that the more frequent brood rearing breaks exhibited by RHBs may not be due to reductions in queen egg laying in response to nutritional stress. We find that the best performing honey bee queen (RHB or IHB) is context dependent due to specific trade-offs in performance, which beekeepers may want to consider in the future for honey bee breeding and management.