Varroa mites are a major risk to honey bee health and are becoming resistant to two substances (coumaphos and fluvalinate) used to manage them. Beekeepers now have a simple assay to figure out whether termites are resistant and hence ensure usage of proper control procedures. Credit: Stephen Ausmus/ARS-USDA
An USDA Agricultural Research Service-developed line of bees that naturally has low levels of Varroa mites is more than two times as most likely to survive the winter season than standard honey bees.
Pol-line honey bees, a kind of Varroa mite resistant honey bee established by the Agricultural Research Service, are more than twice as most likely to survive through the winter than standard honey bees, according to a research study published in Scientific Reports.
Although ARS established Pol-line bees in 2014, this study was the very first time that they were tested head-to-head along with basic honey bee stock in business apiaries offering pollination services and producing honey. Colonies capability to endure winter without being treated to control Varroa termites was followed in 4 states: Mississippi, California, and North and South Dakota.
In this study, Pol-line nests that were provided no treatment to control Varroa mites in the fall had a survival rate of 62.5 percent compared to basic bees nests in industrial apiaries also provided no fall Varroa treatment, which had a winter season survival rate of 3 percent.
When Standard nests and pol-line nests were treated against Varroa mites in both fall and December, Pol-line bees had a winter survival rate of 72 percent while basic bees had a survival rate of 56 percent. So Pol-line bees still had a better winter season survival rate regardless of getting double Varroa mite treatment.
” These survival results continue to highlight the significance of beekeepers requiring to manage Varroa infestations. The capability to have high nest survival with lowered or no Varroa treatments can enable beekeepers to conserve money and time,” said research study molecular biologist Michael Simone-Finstrom, co-leader of the research study with research study entomologist Frank Rinkevich, both with the ARS Honey Bee Breeding, Genetics, and Physiology Research Laboratory in Baton Rouge, Louisiana.
This research study was the conclusion of breeding efforts to establish honey bee colonies with naturally low Varroa populations that started at the Baton Rouge lab in the late 1990s.
Winter nest survival is essential for beekeepers because in February each year, about 2.5 million honey bee colonies are needed in California to pollinate almond crops. Larger, healthier colonies bring beekeepers exceptional pollination contracts at about $220 a colony.Varroa mites can trigger huge nest losses; they are the single biggest issue facing beekeepers since they infect the United States from Southeast Asia in 1987. While miticides used to control Varroa exist, resistance is developing to a few of them.
” We want to change reliance on chemical controls with honey bees like Pol-line that have high mite resistance of their own and carry out well, including high honey production, in business beekeeping operations. Pol-lines high mite resistance is based upon their behavior for eliminating Varroa by expelling infested pupae– where Varroa termites reproduce– a trait called Varroa-sensitive hygiene (VSH),” said Rinkevich.
” Beyond Pol-line bees, we need to create sophisticated and easy breeding choice tools that beekeepers can utilize to choose resistance qualities in their own bees to promote VSH habits in honey bees across the nation,” Simone-Finstrom stated. “The excellent feature of this particular trait is that weve found out honey bees of all types express it at some level, so we understand with the right tools, it can be promoted and selected in everybodys bees.”
Evolutionary ecologist Thomas OShea-Wheller, now with the University of Exeter in England, who dealt with the study while a post-doc with Louisiana State University under teacher Kristen Healy mentioned, “This kind of resistance provides a natural and sustainable solution to the danger postured by Varroa termites. It does not count on chemicals or human intervention.”
In addition, overall winter survival, the scientists examined the levels of infections in Pol-line and basic bee colonies that are typically sent by varroa mites.
The Pol-line nests revealed considerably lower levels of three major infections: Deformed wing virus A, Deformed wing virus B and Chronic bee paralysis virus, all of which can trigger substantial issues for colonies.
” Interestingly, when we took a look at the levels of virus infection individually from the levels of mite problem, we found there wasnt a strong correlation in between viral loads and colony survival. You might not use the level of these viruses as great predictors of colony losses,” Simone-Finstrom stated.
For more on this research study, see New Breed of Honey Bees a Major Advance in Global Fight Against Parasitic Varroa Mite.
Recommendation: “A derived honey bee stock gives resistance to Varroa destructor and associated viral transmission” by Thomas A. OShea-Wheller, Frank D. Rinkevich, Robert G. Danka, Michael Simone-Finstrom, Philip G. Tokarz and Kristen B. Healy, 7 April 2022, Scientific Reports.DOI: 10.1038/ s41598-022-08643-w.
The Agricultural Research Service is the U.S. Department of Agricultures chief clinical internal research firm. Daily, ARS concentrates on solutions to agricultural problems affecting America. Each dollar purchased farming research study results in $17 of financial impact.
Varroa mites are a significant danger to honey bee health and are ending up being resistant to two substances (coumaphos and fluvalinate) utilized to control them. Beekeepers now have a simple assay to identify whether termites are resistant and thus ensure use of suitable control measures. Winter season colony survival is essential for beekeepers because in February each year, about 2.5 million honey bee nests are required in California to pollinate almond crops. Larger, much healthier nests bring beekeepers exceptional pollination agreements at about $220 a colony.Varroa termites can cause huge colony losses; they are the single biggest issue facing beekeepers given that they spread to the United States from Southeast Asia in 1987. While miticides utilized to control Varroa exist, resistance is establishing to some of them.