October 23, 2008
Building A Kinder, Gentler Bee
It's about bee-ing all they can be.
An enhanced-line honey bee stock developed by University of California, Davis bee breeder-geneticist Susan Cobey, that crosses her bee line "New World Carnolians" with "Old World" Carnolians from Germany, shows genetic promise in aiding the troubled bee industry, research reveals."I'm really pleased with the stock," said Cobey, project leader of a honey bee stock improvement grant, funded by the California State Beekeepers' Association and the California Almond Board. "The bees are very gentle, very hygienic and very productive, and hopefully will confer increased resistance to pests and disease."
California Secretary of Agriculture A. G. Kawamura admired the stock during the State Apiary Board meeting Oct. 3 at the Harry H. Laidlaw Jr. Honey Bee Research Facility on the UC Davis campus.
Holding a frame of bees, Kawamara correctly singled out the queen and praised the bees' elegance and gentle temperament. In his youth, he reared honey bees for several years, tending the hives and selling the honey.
The gentleness of her bees did not escape the State Apiary Board, led by newly elected chair Jackie Park-Burris of Palo Cedro, who also serves as president of the California State Beekeepers' Association. They toured Cobey's colonies without protective bee suits, as did Kawamura.
"Sue's bees are polite," said beekeeper Steve Godlin of Visalia, vice chair of the California State Apiary Board.
Cooperative Extension apiculturist Eric Mussen of UC Davis said genetic research is sorely needed. "Although we spend a considerable amount of time trying to find short-term fixes to our honey bee disease and pest control problems, in the long run, the genetic solution of resistant stocks will be a better solution."
"Our focus," Cobey said, "is to identify, select, and enhance honey bee stocks that show increasing levels of resistant to pests and diseases."
Cobey initially developed the New World Carnolians stock, a dark race of honey bees, in the early 1980s by back-crossing stocks collected from throughout the United States to create a more pure strain. "Over time, it has proven very productive, winter hardy, well-tempered and more resistant to pests and disease," she said. "For many years I have wanted to work with pure Carnica. Now I can."
The scientists imported semen from Germany in 2006 and again this year, increasing the purity.
Cobey said genetic diversity, the raw tools for selection, is critical "in maintaining colony fitness and resisting pests and diseases." The honey bee (Apis mellifera), initially brought from Europe to America in 1622 and to California in 1853, is declining in population. Mussen and Cobey attribute the decline to multiple factors: diseases, pesticides, parasites, malnutrition, stress, climate change, and colony collapse disorder, in which bees mysteriously abandon their hives.
Pollination issues plaque the beekeeping industry, Cobey said. "Honey bees pollinate about one-third of the food we eat. Without bees, we wouldn't have the fruits, vegetables and nuts we enjoy. Bees are critical to our food supply, especially in California, the bread basket of the country."
Cobey collaborates with a team of scientists from Canada, Maryland, Minnesota and Washington state. They include viral researcher Michelle Flenniken, the newly selected Häagen-Dazs post-doctoral researcher at UC Davis; reproductive specialists John Pollard and Claire Plante of GeneSafe Technologies, Ltd., Guelph, Canada; apiculturists Steve Sheppard of Washington State University, Pullman, and Marla Spivak of the University of Minnesota, St. Paul; and USDA scientists Jeff Pettis and Judy Chenn of Beltsville, Md.
The scientists obtained importation permits from USDA-APHIS (Animal Plant Health Inspection Service) to import semen for a three-year period, 2008-2010, from three honey bee subspecies, Apis mellifera ligustica from Italy, A. m. carnica from Germany and A. m. caucasica from Turkey. To assure that the stock carries no diseases, the scientists established a quarantine area in an ecological preserve at WSU.
Cobey reared virgin queens from her New World Carnolian genetic line and inseminated these with German carnica semen imported in May. Due to importation delays (permits, inspections, quarantines and shipping) the virgin queens received two-week-old semen, but it was still viable, Cobey said. The queens were recently released from the WSU quarantine and are now at UC Davis for evaluation and propagation.
"Because semen and eggs can transmit viruses, imported stock must be isolated and quarantined. Semen does eliminate the risk of introducing parasites and pests, but viruses remain in question. We need to do this responsibly."
The German Carnica Association, a national program, traces its pedigrees back to the 1950s, Cobey said. More recently the program began taking selected stock to isolated islands and exposing them, without treatment, to varroa mites. The stronger bees, the ones showing more resistance, are crossed and propagated to enhance this trait.
"Both stocks, the New World Carniolan and the German Carnica, are selected for hygienic behavior," Cobey said. Hygienic behavior is the ability to recognize and remove diseased and varroa mite-infested brood from the hive, she explained. The bees also exhibit good grooming behavior; they remove the parasitic mites from themselves and their nestmates. Initial test results show this trait is enhanced by crossing the two lines.Ã‚
The UC Davis scientist will report on her work at the California State Beekeepers' Association's 119th annual convention, set Nov. 11-13 in Harrah's, Lake Tahoe and at the Almond Board Convention in Modesto in early December.
The next step? She and her team will develop protocol for the safe importation of honey bee gametes, eggs and semen. "At present, there is no standard for honey bees, as is common for mammals," she said. Cobey also offers beekeeper training in stock maintenance techniques.
Cobey, who joined the UC Davis Department of Entomology in May 2007 from Ohio State University, has conducted research programs for three decades and is considered one of the world's most renowned bee insemination authorities and instructors. She teaches courses on "The Art of Queen Rearing," "Instrumental Insemination and Bee Breeding" and "Advanced Instruction in Instrumental Insemination," drawing students from throughout the world.
Image 1: A parasitic varroa mite on bee thorax. (Photo by Kathy Keatley Garvey/UC Davis Department of Entomology)
Image 2: Secretary of Agriculture A. G. Kawamura looks at the enhanced line of stock with UC Davis bee breeder-geneticist Susan Cobey. (Photo by Kathy Keatley Garvey/UC Davis Department of Entomology)
Image 3: Queen bee insemination by Susan Cobey in the Harry H. Laidlaw Jr. Honey Bee Research Facility. (Photo by Kathy Keatley Garvey/UC Davis Department of Entomology)
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