University of Minnesota
College of Food, Agricultural and Natural Resource Sciences
http://www.cfans.umn.edu
Go to the U of M home page

Projects

Our goal is to promote the health of bee pollinators. Our primary research focus is on honey bees, ranging from basic studies on mechanisms of social behaviors to applied studies on bee breeding and management. We also study the abundance and diversity of native bee pollinators. We work as a team to provide the richest learning environment for students at all levels and from all backgrounds.

Propolis

Recent PhD (2010), Mike Simone-Finstrom (funded by NSF IOS-0717530) initiated a series of new research projects on propolis, a complex mixture of resins that honey bees collect from some trees, such as poplar and birch in temperate regions. Bees collect the propolis on their hind legs and deposit it in the nest as a form of cement to seal cracks and to line the nest entrance and cavity. Propolis is widely known for its diverse antimicrobial properties and its value as a human medicine. Few studies have investigated the antimicrobial benefits of propolis to bees.

Mike's research focused on the evolutionary benefits of resin collection to honey bees, and the proximate mechanisms that regulate resin collection at the individual and colony-level. We have determined that propolis in the hive allows adult bees to invest less in individual immune function due to its ability to reduce overall bacterial loads in colonies. In this way propolis may reduce stress that bees are exposed to and may increase colony health. Other studies have shown that resin foragers are more sensitive to tactile information than other forager types, which may indicate that tactile cues are relevant in the initiation of resin foraging behavior. We have also recently documented that propolis use by honey bees may be a unique example of self-medication, since resin collection increases after challenge with a fungal parasite.

PhD student, Renata Borba (funded by NSF-IOS-0717530 / NAPPC / NCR-SARE / California Beekeepers Association / Project Apis m.) is continuing the line of research on the benefits of propolis to bees’ immune system by taking her studies to her home country Brazil to study propolis in African-derived honey bees. This race of bees appears to be more resistant to diseases and parasites compared to European-derived honey bees in North America. Is propolis part of their defense? Renata will determine the relative effect of propolis on the immune system of African-derived bee colonies. This comparative study will shed light on ways we can improve the health of our European bees in the U.S. Renata is also examining “propolis trap” configurations that encourage bees to naturally deposit propolis within commercial beekeeping hives and the seasonal effects of propolis to European-derived bee health after a contiguous layer of propolis is deposited surrounding the nest area. She is also studying the role of resin in European-derived bee social immunity after challenge with the bacterial pathogen Paenibacillus larvae.

PhD student, Mike Wilson, (advised by Dr. Jerry Cohen, Plant Biological Sciences, funded by College of Agriculture, Food and Natural Resource Sciences) is studying the chemical components of plant resins from different botanical origins, and is identifying those components that are responsible for the biological activity against bee- and human-related bacteria. His research is focused on (1) using metabolic fingerprinting analysis to identify the plant sources of resin collected by foragers, (2) screening a botanically diverse propolis samples for growth inhibition of Paenibacillus larvae (a honey bee brood pathogen), and (3) using bioassay-guided separation to isolate active compounds in inhibitory propolis samples.

Pathogens and Cell Line

PhD student Mike Goblirsch has developed the first continuous cell line derived from honey bee embryonic tissues; his ongoing research utilizes this research tool to better understand some of the challenges that honey bee are confronted with. An in vitro system derived from honey bee cells will be beneficial for 1) determining how factors such as intracellular pathogens or toxicological agents interact with host cells to negatively affect bee health; 2) developing diagnostic assays and screening novel therapeutics against emerging bee diseases such as viruses; 3) assessing pesticide toxicity, using wells of a culture plate as experimental units instead of entire honey bee colonies; and 4) uncovering regulatory networks and functional evaluation of the honey bee genome through RNA interference (RNAi) gene silencing technology. Importantly, cell culture material is available for distribution to other researchers to foster collaborations and expansion of our understanding of honey bee biology and pathology.

Landscapes effects on Honey Bee Health and Native Bee Diversity

Two PhD students, Matthew Smart and Elaine Evans, are working on this project (funded by USDA-NIFA 2010-65615-20631: Influence of mid-continent land-use trends on floral diversity and pollen availability to sustain bee health, diversity and ecosystem). This is a collaborative project with Dr. Jeff Pettis of the USDA-ARS Bee Lab in Beltsville, MD, and with Dr. Ned "Chip" Euliss of the USGS in Jamestown, ND.

Matthew Smart is studying how varying agricultural and native landscapes during the summer in North Dakota affect honey bee nutritional physiology and immunology, and how these measures change through the winter when commercial honey bee colonies are moved to California for pollination. He is interested in understanding the flow of nutrients, particularly protein, in honey bee colonies and the relationships between landscape nutritional quality/availability and disease – and how this is manifested at the colony and individual bee levels.

Elaine Evans is examining the impact of agricultural intensity and other landscape factors on native bee abundance and diversity in North Dakota. The two main factors determining the value of different landscapes to bees are the presence of potential nesting sites and the presence of nutritional resources (pollen and nectar from flowering plants). The results from this research will be added to a model (EcoServ) that has been developed by researchers at the USGS for forecasting change in ecosystem services under alternate land-use and climate futures. This model can be used to predict landscapes that can best support native bee population.

Improving honey bee and wild bee nutrition in urban landscapes (Bee Lawn)

M.S. student, Ian Lane (funded by MN Environmental and Natural Resources Trust Fund) is studying how commercial turf grasses and flowering plants can be combined to create foraging patches for bees in home lawns. As flowering resources are removed from the landscape by human development, new tools are needed to ensure the health of managed and wild bees. Turf grass represents a significant portion of cultivated land in the United States (40 million acres), and is classically devoid of flowers. Investigating new ways of managing and planting turf lawns with flowering plants holds the potential to greatly improve the foraging resources available to bees in highly developed areas.

Other Native Bees: Orchard mason bees, Osmia

Joel Gardner, M.S. Joel conducted a survey of native bees at Itasca State Park, MN, to compare with a 75 year old museum collection. As widespread interest in bees by both the public and science is relatively recent, looking at museum collections is currently the only way to make long-term comparisons between bee species and look for declines. Joel studied the family Megachilidae (mason and leafcutter bees) for his M.S. degree, and found evidence for some possible declines since 1938, even in a protected area like Itasca State Park. His future work will involve looking at the other four bee families from the park.

Effects of Neonicotinyl Pesticides on Honey Bees and Bumblebees

PhD student, Judy Wu (Department of Entomology, Univ MN; Funded by EPA star fellowship) Sub-lethal effects of neonicotinyl insecticides on honey bee and bumble bee queens and colony development. Judy is examining potential adverse sub-lethal effects of neonicotinoid colony exposure on queen honey bee and bumble bee behavior, specifically egg-laying rate and mobility. She is also examining the sub-lethal effects of exposure on colony development including brood production, worker foraging rates, and worker hygienic behavior or the ability to detect and remove diseased and or mite-infested brood.

Tech-Transfer Teams: Helping Commercial Beekeepers

PhD Student, Katie Lee, heads the Midwest Tech-Transfer Team, a part of the Bee Informed Partnership (beeinformed.org). Tech-Transfer Teams are modeled after crop consultants of the agriculture industry. Tech-Teams help beekeepers monitor diseases and pests, and test potential breeder colonies for disease resistance. Her objectives are to quantify the success of the selection progress in hygienic behavior by commercial honey bee breeders, and to examine colony losses in commercial operations using an epidemiological model.

Honey Bee Hygienic Behavior and Bee Breeding

Our primary and long-term goal (M. Spivak and G. Reuter) is to help honey bees and beekeepers reduce the amount of antibiotics and pesticides used in beehives to control diseases and parasitic mites. We have been breeding bees for resistance to these maladies since 1993 with the aim of "getting bees back on their own six feet" to end their reliance on chemical treatments for survival. A reduction in the use of antibiotics and pesticides will reduce operating costs for beekeepers, while ensuring healthy, strong colonies for honey production and pollination, and the purity of honey, wax and other marketable bee products.

Hygienic behavior of honey bees is the main mechanism of resistance to the devastating bacterial disease, American foulbrood, and the fungal disease, chalkbrood. Hygienic bees detect and remove infected brood from the nest before the pathogen becomes infectious. In 1993, we began by breeding a line of honey bees for hygienic behavior with the goal of testing if the behavior is also an effective mechanism of resistance to the parasitic mite, Varroa destructor. Extensive field trials at the University and in collaboration with commercial beekeepers have shown that bees bred for hygienic behavior do detect and remove mite-infested worker brood, and colonies bred for the behavior have reduced mite loads compared to unselected control colonies.

Although our "MN Hygienic" line of bees is sold throughout the U.S., our current emphasis is helping beekeepers and bee breeders select for this and other resistance traits from among their own lines of bees. We are working closely with three Minnesota beekeepers to certify that their stocks are hygienic. Read about it: The future of the MN Hygienic stock of bees is in good hands!. We are also working one-on-one with members of the California Bee Breeders Association to help them select for disease and mite-resistance from among their tried-and-true stocks.

Our aim, is to promote genetic diversity, resilience and healthy bees, and we feel that working directly with queen breeders is the best way to accomplish our goal.