Source:University of Maryland
Honey bee colonies around the world are at risk from a variety of threats, including pesticides, diseases, poor nutrition and habitat loss. Recent research suggests that one threat stands well above the others: a parasitic mite, Varroa destructor, which specializes in attacking honey bees.
In this electron micrograph, a parasitic mite, Varroa destructor, is wedged between the abdominal plates of a honey bee’s exoskeleton.
Credit: UMD/USDA/PNAS
For decades, researchers have assumed that varroa mites feed on blood, like many of their mite and tick cousins. But new University of Maryland-led research suggests that varroa mites instead have a voracious appetite for a honey bee organ called the fat body, which serves many of the same vital functions carried out by the human liver, while also storing food and contributing to bees’ immune systems.
The research, published in the Proceedings of the National Academy of Sciences on January 14, 2019, could transform researchers’ understanding of the primary threats to honey bees while pointing the way toward more effective mite treatments in the future.
“Bee researchers often refer to three Ps: parasites, pesticides and poor nutrition. Many studies have shown that varroa is the biggest issue. But when compromised by varroa, colonies are also more susceptible to the other two,” said UMD alumnus Samuel Ramsey (Ph.D. ’18, entomology), the lead author of the paper. “Now that we know that the fat body is varroa’s target, this connection is now much more obvious. Losing fat body tissue impairs a bee’s ability to detoxify pesticides and robs them of vital food stores. The fat body is absolutely essential to honey bee survival.”
In addition to breaking down toxins and storing nutrients, honey bee fat bodies produce antioxidants and help to manage the immune system. The fatty organs also play an important role in the process of metamorphosis, regulating the timing and activity of key hormones. Fat bodies also produce the wax that covers parts of bees’ exoskeletons, keeping water in and diseases out.
Read more and see the original article here: https://www.sciencedaily.com/releases/2019/01/190114161137.htm
