Combating Varroa destructor in Honeybee Colonies Using Flumethrin or Fluvalinate

Abstract

Gregorc A., M. I. Smodi‰ ·kerl: Combating Varroa destructor in Honeybee Colonies Using Flumethrin or Fluvalinate. Acta Vet. Brno 2007, 76: 309-314.Mite mortality in two apiaries, one with 32 and the other with 15 honeybee (Apis mellifera carnica) colonies, was recorded prior to and after flumethrin or fluvalinate treatments and after a control, oxalic-acid application. During the 42-and 51-day pre-treatment periods, the average daily natural mite drop was 0.04 (± 0.04) and 2.82 (± 2.19), respectively, which represents 1.09% (± 1.06) and 3.84% (± 3.04) of the total number of mites found during the experiment. The flumethrin or fluvalinate applications resulted in an average mite mortality at the two apiaries of 214.46 (± 260.02) and 4,098.64 (± 2,508.31). The treatments resulted in a 19.11% (± 14.62) and a 39.28% (± 10.47) reduction in the number of mites in slightly infested colonies and 94.30% (± 4.26) and 96.24% (± 3.14) in highly infested colonies. The difference in treatment efficacy between both apiaries was significant (P < 0.001) and indicates that fluvalinate and flumethrin are highly efficacious in dealing with highly infested honeybee colonies with sealed brood. The importance of effective mite control in colonies with a high level of natural mite mortality is discussed in this study. Acaricides, control methods, Apis mellifera, oxalic acid, mite infestationAcaricides are regularly applied to honeybee colonies in order to maintain their productivity. These are usually synthetic and their lipophilic and persistent characteristics result in a build-up of their residues in the wax and honey (Wallner 1999).The varroa mite has already developed a resistance to several synthetic acaricides (Milani 1999;Lodesani et al. 1995;Miozes-Koch et al. 2000;Floris et al. 2001;Spreafico et al. 2001) and beekeepers are increasingly turning to alternative treatments incorporating essential oils and organic acids (Mutinelli et al. 1997;Melathopoulos and Gates 2003;Gregorc and Poklukar 2003).The efficacy of fluvalinate and flumethrin in killing mites is long-lasting. Fluvalinate is available under the trade names Apistan (used against varroa mites in bee colonies), Klartan and Mavrik, while flumethrin is available under the trade name Bayvarol, which is specific for varroa control. Oxalic acid (OA) has been found to be highly effective in treating colonies without brood (Imdorf et al. 1997;Br∅dsgaard et al. 1999). Efficacy of 95% was achieved after three treatments using a 5% OA solution (Mutinelli et al. 1997) and efficacy of 24% after one springtime treatment administered by trickling when a capped brood was present (Br∅dsgaard et al. 1999). In our previous experiments the quantity of OA solution used to treat one normally developed colony was approximately 50 millilitres and we found that three OA treatments of colonies with brood had efficacy of 39.2%, and 99.4% when there was no brood present (Gregorc andPlaninc 2001 and2004a).This study was designed to evaluate the effectiveness of fluvalinate and flumethrin...

Control of Varroa destructor Mite Infestations at Experimental Apiaries Situated in Croatia

“…Comparing the relative efficacy of the used varroacides with different active ingredients (Figure 6a), the best effect was achieved for honey bee colonies from an A experimental group, and lowest for colonies from a B experimental group, where statistically significant difference was affirmed (p < 0.05; F = 6.93). Although the organic acaricides have certain advantages after repeated use, their efficacy may be inconsistent and more variable compared with synthetic acaricide formulations [24,[33][34][35][36], which is also confirmed with our results.…”

Biology and control of Varroa destructor

“…Viruses, bacteria (BT), protozoa, nematodes, rickettsiae Pathogens cause lethal infections on mites Some strains of Bacillaceae and Micrococcaceae increased mortality in in vitro tests; until now no Varroa-specific strains known Aronson et al (1986), Ball and Allen (1988), Glinski and Jarosz (1990), Tsagou et al (2004), Van der Geest et al (2000) P. Rosenkranz et al / Journal of Invertebrate Pathology 103 (2010) S96-S119 S111 natural downfall of 0.5-10 mites on the bottom board is regarded to be the threshold for a basic necessity of treatment (Arbeitsgemeinschaft der Institute für Bienenforschung e.V., 2007; Gregorc and Smodis Skerl, 2007;Liebig, 2001;Martin, 2001b). This corresponds to an absolute mite population of 2000-3000 mites which is considered as an economic threshold (Delaplane and Hood, 1999).…”

“…Compared to other diagnostic methods like acaricidal treatment, alcohol or detergent washes of adult bee and brood samples (Gregorc and Smodis Skerl, 2007;Rinderer et al, 2004) the measurement of the natural mite mortality is easy, cheap and fast. Depending on season and on the amount of brood, a Biological/antagonists Benign haplotype of Varroa Varroa mites' reproduction is influenced by competition for resources in multiply infested cells.…”

The acaricidal effect of flumethrin, oxalic acid and amitraz against Varroa destructor in honey bee (Apis mellifera carnica) colonies

“…It has been found that this level of natural mite mortality allows the successful use of alternative mite control treatments such as oxalic acid A or thymol (Gregorc and Planinc 2005). It has also been found that in colonies with a low infestation level, fluvalinate and flumethrin were effective enough to allow colony survival during the winter (Gregorc and Smodiš Škerl 2007). The number of mites fallen from our experimental colonies during the present study indicates a moderate level of overall infestation, thus allowing the use of less effective control treatments.…”