Discovery of Stilbene Acaricides for Managing the Honey Bee Pest, Varroa destructor

The ectoparasitic varroa mite (Varroa destructor) is a major pest of the honey bee and contributes to significant declines in honey bee populations worldwide. The varroa mites rely on bees to survive and reproduce, and can consequently lead to physiological deficiencies and disease transmission that compromise the health of honey bee colonies. The varroa mite nervous system is an established target site for existing acaricide chemistries. These acaricides have shown adverse health effects on honey bees, while resistance to these chemistries limits their use to effectively reduce varroa mite infestations. The voltage-gated chloride channel is involved in the maintenance of nerve and muscle excitability in arthropod pests, which suggests that this target site can be exploited for novel acaricide chemistries.  We will report a toxicological analysis of a natural stilbene product, and related analogs, against acaricide-susceptible and -resistant varroa mite populations. The information gathered in this study will be discussed with regard to the target-site discovery and development of novel chemistries for varroa mite management.