1a. Objectives (from AD-416)
The long-term objective of this project is to develop the economic value of Russian honey bees (RHB) through genetic improvements and devise innovative management strategies to increase the stock’s general and pollination productivity. Over the next five years, we will focus on multiple interrelated projects with the following objectives: Objective 1: Develop procedures for identification of RHB as a stock certification tool, determine the genetic makeup of feral bees, and identify genes contributing to mite resistance and survivability. Objective 2: Develop management techniques (e.g., determine economic thresholds for mite treatment, develop cultural techniques for small hive beetle (SHB) management in standard and nucleus colonies, and determine winter management and spring build-up strategies) to build RHB populations for crop pollination (e.g., for almond). Objective 3: Determine if there are genetic components of RHB response to emerging problems (such as colony collapse disorder or CCD) once syndromes and causes are identified. Objective 4: Use traditional breeding techniques to develop RHB with improved economic traits. Objective 5: Develop procedures for routine identification of sex alleles and determine queen relationships in multiple queen colonies.
1b. Approach (from AD-416)
Honey bees play a vital role in the pollination of agricultural crops valued at $14.6B annually. Demands for commercial pollination are steadily growing. However, meeting these demands is increasingly difficult due to serious biological problems. Varroa destructor, Acarapis woodi, Aethina tumida [small hive beetle (SHB)], the emerging problems of colony collapse disorder (CCD) and high winter loss of pollination colonies all are plaguing the beekeeping industry. Perhaps Israeli Acute Paralysis Virus (IAPV) and Nosema ceranae, both recently discovered in the United States will join this list of serious problems. 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: Breeding 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.
3. Progress Report
Research and technology transfer related to breeding Russian honey bees (RHB) has resulted in the complete transfer of all Russian honey bee lines to industry where further selection is underway. Using microsatellite and SNP DNA markers, a combination of marker frequencies was determined to identify Russian honey bees for stock certification purposes and is now being used to evaluate potential breeder colonies in selection programs. A parental population of Russian colonies that have superior early-spring build-up has been selected and the production of a first selected generation is proceeding. The evaluation of crosses of tracheal-mite-resistant Russian bees with non-resistant Italian bees showed that Russian bee resistance to tracheal mites is founded on several genes with some having strong dominance and others having additive effects. Management research on Russian honey bees has determined that Russian colonies will grow larger in smaller 8-frame hives, especially when fed a continual supply of protein and sugar syrup. Longevity of worker bees from individual colonies produced in the autumn is correlated to the survival of workers in winter clusters, providing a useful estimate of colony longevity. The bee diet developed at the ARS lab in Tucson produced larger colonies than other diets in feeding trials with colonies overwintered in California prior to almond pollination. General varroa mite related research indicates that the feral population of honey bees in Louisiana has resurged owing to one or more of several explanations. In Italian colonies, higher levels of varroa mite infestation which are still below thresholds suggested for treatment cause the loss or the early supersedure of introduced queens. Small Hive Beetle (SHB) research has found that Russian honey bees are more resistant to SHB than Italian colonies and that SHB populations develop well even in apiaries having heavy clay soils. CCD research has shown that Russian and VSH varroa-mite-resistant colonies survived as well as treated Italian controls on a multi-location commercial pollination circuit. Overall, the mite resistant stocks were as effective as pollinators as the control stock. A molecular genetic procedure to detect and quantify Nosema apis and N. ceranae was perfected to monitor this disease in selection programs.
1. The accomplishment, Russian honey bees are resistant to the small hive beetle should result in beekeepers being more vigilant with efforts to control the small hive beetle (SHB). The small hive beetle is an increasingly serious problem for beekeepers in the southeastern United States. Small colonies used to produce queen bees for sale are especially vulnerable. However, even large healthy colonies can be quickly overrun by beetles after normal beekeeping manipulations. In a comparative study, Russian honey bee colonies were found to harbor fewer adult beetles than did colonies of Italian honey bees. Although this comparative resistance is not sufficient to entirely prevent colonies from being devastated by SHB it is an additional advantage for beekeepers using Russian honey bees.
2. The accomplishment, Genetic dominance controls Russian honey bee resistance to tracheal mites provides beekeepers with the knowledge that they can mitigate tracheal mite problems by using Russian hybrid bees as well as pure Russian bees. Tracheal mites are a serious parasite of honey bees. United States stocks are generally very susceptible to tracheal mites since their first exposure to the pest was only about 25 years ago. Russian honey bees recently imported from Asia were found to have excellent resistance to tracheal mites but the genetic control of the resistance was not understood. From an analysis of the parents and the progeny of several different crosses between resistant Russian queens and susceptible queens it was determined that the regulation is polygenic with a number of genes with major dominance interacting with minor genes. Beekeepers can benefit from this resistance by either using pure Russian queens or queens resulting from outcrosses of Russian queens.
5. Significant Activities that Support Special Target Populations
Presentations about various aspects of the project were delivered by several staff to the two major national beekeeping organizations (American Honey Producers Association and Apiary Inspectors of America jointly and American Beekeeping Federation) annual meetings. A laboratory field day was held on Saturday, October 18, 2008, for about 100 beekeepers from the region. Beekeeping and research activities were shown ranging from simple for beginners to complex for commercial operators and specialized hobbyists.
Villa, J.D., Rinderer, T.E. 2008. Inheritance of Resistance to Acarapis woodi (Acari: Tarsonemidae) in Crosses Between Selected Resistant Russian and Selected Susceptible U.S. Honey Bees (Hymenoptera: Apidae). Journal of Economic Entomology 101(6):1756-1759(4).