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. 2021 Jan 4;12(1):27.
doi: 10.3390/insects12010027.

Large-Scale Monitoring of Resistance to Coumaphos, Amitraz, and Pyrethroids in Varroa destructor

Affiliations

Large-Scale Monitoring of Resistance to Coumaphos, Amitraz, and Pyrethroids in Varroa destructor

Carmen Sara Hernández-Rodríguez et al. Insects. .

Abstract

Varroa destructor is an ectoparasitic mite causing devastating damages to honey bee colonies around the world. Its impact is considered a major factor contributing to the significant seasonal losses of colonies recorded every year. Beekeepers usually rely on a reduced set of acaricides to manage the parasite, usually the pyrethroids tau-fluvalinate or flumethrin, the organophosphate coumaphos, and the formamidine amitraz. However, the evolution of resistance in the mite populations is leading to an unsustainable scenario with almost no alternatives to reach an adequate control of the mite. Here, we present the results from the first large-scale and extensive monitoring of the susceptibility to acaricides in the Comunitat Valenciana, one of the most prominent apicultural regions in Spain. Our ultimate goal is to provide beekeepers with timely information to help them decide what would be the best alternative for a long-term control of the mites in their apiaries. Our data show that there is a significant variation in the expected efficacy of coumaphos and pyrethroids across the region, indicating the presence of a different ratio of resistant individuals to these acaricides in each population. On the other hand, the expected efficacy of amitraz was more consistent, though slightly below the expected efficacy according to the label.

Keywords: TaqMan; acaricide resistance; acaricides; bioassay; genotyping; honey bees.

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Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection of samples, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1
Figure 1
Bioassays with Varroa destructor. (A) Parasitized bee pupae extracted from the brood cells. (B) Female mites laid on top of the acaricide strip inside a Petri dish. (C) Mortality was evaluated by assessing the movement of mites after probing them with a fine paint brush.
Figure 2
Figure 2
Expected efficacy of commercial acaricides against Varroa destructor in the 2018 season (A) and 2019 season (B). Each dot corresponds to the sample from an apiary. Long horizontal bars represent the mean values and error bars indicate the standard deviation (SD). For Checkmite+, Apitraz, Amicel, and Apivar, the expected efficacy corresponds to mortality recorded in the bioassays. The expected efficacy of pyrethroids-based acaricides was estimated using the frequency of pyrethroid-resistant (RR) and susceptible mites (SS + SR) after genotyping individual mites for the presence of different alleles of the mutation L925V at the V. destructor VGSC.
Figure 3
Figure 3
Sampling locations and expected efficacy (expressed as percentage) of acaricides against Varroa destructor in 2018 season. (A) Checkmite+ (efficacy in blue); (B) Apitraz (efficacy in dark green); (C) Amicel Varroa (efficacy in light green); (D) Pyrethroid-based acaricides (efficacy in pink).
Figure 4
Figure 4
Sampling locations and expected efficacy (expressed as percentage) of acaricides against Varroa destructor in the 2019 season. (A) Checkmite+ (efficacy in blue); (B) Apitraz (efficacy in dark green); (C) Apivar (efficacy in light green); (D) Pyrethroid-based acaricides (efficacy in pink).
Figure 5
Figure 5
Last acaricide treatment carried out (%) in the apiaries that provided combs for this study in the 2018 and 2019 seasons.

References

    1. Rosenkranz P., Aumeier P., Ziegelmann B. Biology and control of Varroa destructor. J. Invertebr. Pathol. 2010;103:S96–S119. doi: 10.1016/j.jip.2009.07.016. - DOI - PubMed
    1. Boecking O., Genersch E. Varroosis—The ongoing crisis in bee keeping. J. Consum. Prot. Food Saf. 2008;3:221–228. doi: 10.1007/s00003-008-0331-y. - DOI
    1. Ramsey S.D., Ochoa R., Bauchan G., Gulbronson C., Mowery J.D., Cohen A., Lim D., Joklik J., Cicero J.M., Ellis J.D., et al. Varroa destructor feeds primarily on honey bee fat body tissue and not hemolymph. Proc. Natl. Acad. Sci. USA. 2019;116:1792–1801. doi: 10.1073/pnas.1818371116. - DOI - PMC - PubMed
    1. Genersch E., Von Der Ohe W., Kaatz H., Schroeder A., Otten C., Büchler R., Berg S., Ritter W., Mühlen W., Gisder S., et al. The German bee monitoring project: A long term study to understand periodically high winter losses of honey bee colonies. Apidologie. 2010;41:332–352. doi: 10.1051/apido/2010014. - DOI
    1. Guzmán-Novoa E., Eccles L., Calvete Y., Mcgowan J., Kelly P.G., Correa-Benítez A. Varroa destructor is the main culprit for the death and reduced populations of overwintered honey bee (Apis mellifera) colonies in Ontario, Canada. Apidologie. 2010;41:443–450. doi: 10.1051/apido/2009076. - DOI

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