Abstract
Base levels of Varroa destructor resistance to four synthetic chemicals were established in new Zealand during May through August 2003. The four chemicals—amitraz, coumaphos, flumethrin, and fluvalinate are currently used, or may in the future be registered for use, in new Zealand. Resistance was measured by placing mites on paraffin wax impregnated with the chemicals. The lC50 estimate, adjusted for natural mite mortality, for amitraz was 110 μg/g, and >200 μg/g for coumaphos, 12 μg/g for flumethrin, and 1269 μg/g for fluvalinate. A comparison with international data indicates that new Zealand populations are not currently resistant to flumethrin. The LC50 for two Italian locations with mites resistant to fluvalinate was 385 and 857 μg/g, and 16–17 μg/g for non‐resistant varroa (Milani 1995). Whether the adjusted LC50 for fluvalinate in this trial (1269 μg/g) would be observed as resistance in the field in New Zealand is unknown. Because this is the first time these tests have been conducted in New Zealand it is not known whether this level of resistance was present when varroa arrived in new Zealand or whether it has since developed.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: New Zealand Journal of Crop and Horticultural Science
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
