- Nuts: almonds
- Additional Plants: native plants, ornamentals
- Animals: bees
- Animal Production: general animal production
- Education and Training: workshop
- Pest Management: genetic resistance
Honey bee (Apis mellifera) populations are in decline, due to stressors which include pesticides, parasites, pathogens and poor nutrition. This decline poses a significant threat to food security, crop productivity and farmer income in the United States, as honey bees are the primary and sometimes exclusive pollinators of the majority of our fruit, vegetable, and nut crops. Due to the complexity of the stressors affecting bees, the only viable long-term sustainable solution is the selection and breeding of honey bee stocks that are more resistant to diseases and parasites, more effective at provisioning the colony with nutritional resources, and have higher rates of overwintering survival. Unfortunately, widespread adoption of stock improvement efforts is not currently possible because tools to naturally manipulate honey bee mating are not available. Thus, breeders must use instrumental insemination to control mating: this process is time consuming, requires sophisticated instrumentation and training, and may have detrimental effects on queen bees. Developing methods to naturally control honey bee mating behavior are thus critical for widespread adoption of honey bee stock improvement practices in the US. The primary objective of this proposal is to identify pheromonal tools that control male honey bee sexual maturation and the formation of their mating swarms. Identifying these factors will allow us to develop methods to facilitate controlled natural honey bee mating in stock improvement programs using easily accessible tools and management practices. The proposed studies will also significantly advance our understanding of how chemical communication mediates mating and reproduction in honey bees.
Project objectives from proposal:
Objective 1: Characterize the effect of the queen pheromone, 9-ODA, on the rate of drone sexual maturation.
Our preliminary studies indicate that exposure to 9-ODA, the major component of queen pheromone, reduced levels of juvenile hormone and increased levels of vitellogenin in drones. In workers, 9-ODA has similar effects, and this leads to slowed behavioral maturation maturation (Pankiw, 1998). Thus, drones might mature faster in queenless colonies (which lack 9-ODA) and the addition of 9-ODA may slow down this maturation process. We will test this hypothesis. If 9-ODA does regulate sexual maturation, beekeepers can use this pheromone to control the timing of drone production and synchronize it with queen production.
Sexually mature drones fly out of the colony and aggregate at specific drone congregation areas (DCAs) with other drones as they wait to mate with virgin queens. Previous studies have demonstrated that drone mandibular gland extracts can attract drones from a distance, and thus may produce a pheromone that facilitates formation of these aggregations(Lensky, 1985). We will 1) characterize the contents of the drone mandibular gland using gas chromatography-mass spectroscopy (GC-MS), 2) determine if drones are attracted to specific chemicals in the extract and form drone congregation areas near lures containing these chemicals. If, as we hypothesize, we can use these chemicals to control DCA formation, it would allow the beekeepers to develop these sites in close proximity to breeding populations.
Objective 3: Disseminate the practical outcomes of these objectives to beekeepers and bee breeders.
The results of these studies will yield tools that can be implemented to facilitate controlled natural mating in honey bees, and so it will be of critical importance to disseminate findings as they become available. I will plan to relay project findings at Penn State University’s Queen Rearing Workshop and at local and national beekeeper meetings.
Objective 1: This project will be initiated in June 2014 and completed in August 2014. Samples collected from this project will be processed for molecular studies early in September 2014, along with the associated behavioral data. Results from this project will be presented at the annual PA State Beekeeper meeting in November 2014 and prepared for publication by December 2014.
Objective 2: This project will be initiated in July 2014 and will terminate in September 2014. If the project has not been completed by this time, it will be repeated and completed in June 2015. Results will be presented at the yearly Queen Rearing Workshop Grozinger organizes (May 2015), at the national meeting of the American Association of Professional Apiculturists in early 2015, and be prepared for publication by March 2015.
Objective 3: The timeline for this outreach objective has been integrated into the timetable for objectives 1 and 2 (above).