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Varroa destructor Anderson & Trueman (Acari: Varroidae) is of paramount significance in modern beekeeping, with infestations presenting a primary challenge that directly influences colony health, productivity, and overall apicultural sustainability. In order to control this mite, many beekeepers rely on a limited number of approved synthetic acaricides, including the pyrethroids tau-fluvalinate, flumethrin and organophosphate coumaphos. However, the excessive use of these substances has led to the widespread development of resistance in various beekeeping areas globally. In the present study, the occurrence of resistance mutations in the voltage-gated sodium channel (VGSC) and acetylcholinesterase (AChE), the target-site of pyrethroids and coumaphos, respectively, was examined in Varroa populations collected throughout the southeastern and eastern Anatolia regions of Türkiye. All Varroa samples belonged to the Korean haplotype, and a very low genetic distance was observed based on cytochrome c oxidase subunit I (COI) gene sequences. No amino acid substitutions were determined at the key residues of AChE. On the other hand, three amino acid substitutions, (L925V/I/M), previously associated with pyrethroid resistance, were identified in nearly 80% of the Turkish populations. Importantly, L925M, the dominant mutation in the USA, was detected in Turkish Varroa populations for the first time. To gain a more comprehensive perspective, we conducted a systematic analysis of the distribution of pyrethroid resistance mutations across Europe, based on the previously reported data. Varroa populations from Mediterranean countries such as Türkiye, Spain, and Greece exhibited the highest frequency of resistance mutation. Revealing the occurrence and geographical distribution of pyrethroid resistance mutations in V. destructor populations across the country will enhance the development of more efficient strategies for mite management. [ABSTRACT FROM AUTHOR]

Spider mites lead to significant damage in the areas where apple is produced. Chemical control is generally preferred in the control of spider mites and other pests in Turkey. Today, many negative aspects of chemical control have turned up. Spider mites have a lot of natural enemies and knowing their activities is important. Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is a predator species which is used to control against spider mites. In this study, activities and release ratio of predator N. californicus that is control against spider mites in apple orchards are determined. For this purpose, two different experiments were established in two different apple orchards in Çavundur village and Alcıklar neighborhood in Şarkikaraağaç district of Isparta province. The study was established according to random trial parcels. 25, 50 or 100 predatory mites (NC) were released per tree in parcels. No application has been used for control. In the orchards located in Çavundur village where N. californicus has been relased, control, 25, 50 and 100 NC/tree in 63rd day, 10.31, 2.58, 1.96, 1.69 spider mite moving stages (ms)/leaf and 8.09, 1.11, 0.66 and 1.16 egg/leaf have been found. In Alcıklar neighborhood, control, 25, 50 and 100 NC/tree release 63rd day 4.53, 1.02, 0.49, and 0.49 ms/leaf and in the same order 3.11, 0.67, 0.36 and 0.31 egg/leaf has been detected. Finally, As a result, red spider populations were suppressed at different times compared to the control in all treatments. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is the most economically important mite pest in agricultural areas and chemical acaricides are widely used to control T. urticae populations. Cyflumetofen is a recently introduced acaricide that inhibits the mitochondrial electron transport chain at complex II (succinate dehydrogenase, SDH), which represents the most recently developed mode of action for mite control worldwide. In the present study, started upon the launch of cyflumetofen in Turkey, a five-year survey was performed to monitor cyflumetofen susceptibility in 28 T. urticae populations collected from agricultural fields across the country. The first resistance case that might cause control failure in practical field conditions was uncovered in 2019, three years after the registration of cyflumetofen. In addition, an extremely resistant population (1722-fold resistance) was also detected towards the end of 2019. Cyflumetofen resistance did not decrease in the laboratory after relaxation of selection pressure for over one year in field-collected populations, suggesting the absence of a fitness cost associated with resistance in these populations. Next to phenotypic resistance, metabolic and physiological mechanisms underlying the decreased susceptibility were also investigated. Synergism assays showed the involvement of P450 monooxygenases in cyflumetofen resistance. Downregulation of carboxylesterases as resistance mechanism, is underpinned by the fact that pre-treatment with esterase inhibitor DEF decreased cyflumetofen toxicity in field-collected strains. Furthermore, a novel H258L substitution in the subunit B of complex II was uncovered in a field population. In silico modeling of the new mutation suggested that the mutation might indeed influence toxicity to complex II inhibitors cyenopyrafen and pyflubumide, but most likely not cyflumetofen. However, further studies are needed to uncover the exact role of this mutation in resistance to this new class of complex II inhibitors. [Display omitted] • Cyflumetofen resistance was monitored in Turkish T. urticae populations for five years. • More than 1700-fold resistance was detected only three years after its introduction. • P450 inhibitor PBO significantly synergized the cyflumetofen toxicity. • A H258L mutation in subunit B of SDH was uncovered. • The potential role of new mutation in resistance was studied with molecular modeling. [ABSTRACT FROM AUTHOR]

Tetranychus urticae Koch (Acari: Tetranychidae) is one of the key pests causing economic losses in vegetable fields. Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) is used effectively in the biological control of this mite on many vegetable crops. The present study determined how different crops such as pepper, eggplant, cucumber and tomato affected the biological control of T. urticae when using P. persimilis in the field-grown vegetables in the Çanakkale of northwestern part of Turkey in 2016 and 2017. Predatory and prey mites were released at a ratio of 1:10 predator:prey on host plants and their numbers on leaves were counted weekly for a period of 8 weeks. The highest number of T. urticae and P. persimilis were counted on cucumber with 108.70 ± 8.14 and 81.00 ± 6.00 mites per leaf in 2016, and with 113.30 ± 10.95 and 24.00 ± 4.58 mites per leaf in 2017, respectively. Also, there was a significant difference for both the populations of T. urticae and P. persimilis on the crops on all weeks in both years. It was revealed that P. persimilis markedly suppressed T. urticae on eggplant and tomato compared to pepper and cucumber in both years. It is clear that the host crops is a key factor on the success of P. persimilis on the biological control of T. urticae on field-grown vegetables. Consequently, it is thought that these results should be taken into account in the biological control strategies of mite pests by using the predatory mites on field-grown vegetables. [Display omitted] • The highest number of T. urticae and P. persimilis were counted on cucumber in 2016 and 2017. • Significant difference for both the populations of T. urticae and P. persimilis on the crops on all weeks in both years. • P. persimilis markedly suppressed T. urticae on eggplant and tomato compared to pepper and cucumber in both years. • The host crops is a key factor on the success of P. persimilis on the biological control of T. urticae on vegetables. [ABSTRACT FROM AUTHOR]