2012 Annual Report
The Russian honey bees (RHB), developed by this unit, are resistant to varroa and tracheal mites, harbor fewer SHB, are excellent honey producers and overwinter well. This research is focused on further improving RHB to increase the stock’s usefulness, especially for early season pollination via stock selection and the development of management procedures. Increasing the commercial acceptability of this mite-resistant stock may mitigate colony losses since commercial beekeepers who use RHB stock for almond pollination report only modest winter loss of colonies. Relevance to Action Plan: Marker assisted selection is a tool being developed in Baton Rouge, Louisiana. This work will be accelerated through additional funding for Russian bees. The problem to be addressed is relevant to the NP 305 Action Plan, Component 2 Bees and Pollination (Honey Bees) Problem Problem Statement 2A.3 Developing and Using New Research Tools: Genomics, Genetics, Physiology, Germplasm Preservation, and Cell Culture.
Management research on Russian honey bees has determined that Russian colonies will grow larger when are fed a continual supply of a patty that is made of protein supplement and either 50% or 25% natural pollen along with a source of sugar syrup. Longevity of worker bees from individual colonies produced in the autumn is correlated to the survival of workers in winter clusters. However, this correlation was not found with worker bees caged from the colonies in the spring. Varroa mites that are released from cells they are infecting because of honey bee hygienic behavior are in a state of asynchronous development with other potential honey bee brood at the time of release. This asynchrony causes the mites to be infertile should they re-invade the brood. Auto- and allo-grooming against varroa mites results in many mites falling to the bottom of the hive that do not have apparent physical damage. Hence, assessments of grooming behavior must be refined to accommodate this observation. An improved method for marking varroa mites for capture/recapture studies was developed.
A quantitative trait loci (QTL) was identified for larval resistance to the fungus causing chalkbrood. Due to the success of the project and the potential for the gene marked by the QTL to impart resistance to a second fungal problem of honey bees, Nosema (N.) ceranae, the project was extended to identify the causative factor in the larval mediated chalkbrood resistance. Fine mapping has reduced the QTL interval to a very small number of genes which are currently being evaluated for resistance function. Colony Collapse Disorder (CCD) research has shown that Russian and VSH varroa mite resistant colonies survived better than untreated Italian colonies in both cross country pollination studies and in trials in a mid-western to California pollination trial. Overall, the mite resistant stocks were equal and in some cases better pollinators than the control stock. Molecular genetic methods have been developed to detect and quantify Nosema ceranae infections. Patrilines of Russian honey bee colonies have variance in response to N. ceranae although Italian colonies do not. This indicates that the potential for breeding bees that have improved resistance to N. ceranae is greater for Russian honey bees. Feeding pollen or protein substitute to honey bee colonies through the winter increases the levels of infection of colonies by N. ceranae.
Bourgeois, A.L., Rinderer, T.E., Sylvester, H.A., Holloway, B.A., Oldroyd, B.P. 2012. Patterns of Apis mellifera infection by Nosema ceranae support the parasite hypothesis for the evolution of extreme polyandry in eusocial insects. Apidologie. 43(5):539-548.
De Guzman, L.I., Frake, A.M., Rinderer, T.E. 2011. Marking small hive beetles with thoracic notching: Effects on longevity, flight ability and fecundity.. Apidologie. 42(1):1-10.
Munday, M., Rinderer, T.E., Rueppell, O. 2012. Ovariole number and ovary activation of Russian honeybee workers (Apis mellifera L.). Journal of Apicultural Research. 51(1):147-149.
Holloway, B.A., Sylvester, H.A., Bourgeois, A.L., Rinderer, T.E. 2012. Association of single nucleotide polymorphisms to resistance to chalkbrood in Apis mellifera. Journal of Apicultural Research. 51(2):154-163.
Bourgeois, A.L., Beaman, G.D., Holloway, B.A., Rinderer, T.E. 2012. External and internal detection of Nosema ceranae on honey bees using real-time PCR. Journal of Invertebrate Pathology 109:323-325
Kirrane, M.J., De Guzman, L.I., Rinderer, T.E., Frake, A.M., Wagnitz, J.J., Whelan, P.M. 2011. Asynchronous development of Honey Bee host and Varroa destructor (Mesostigmata: Varroidae) influences reproductive potential of mites. Journal of Economic Entomology. 104(4):1146-1152.
Kirrane, M.J., De Guzman, L.I., Rinderer, T.E., Frake, A.M., Wagnitz, J.J., Whelan, P.M. 2012. A method for rapidly marking adult varroa mites for use in brood inoculation experiments. Journal of Apicultural Research. 51(2):212-213.