Predatory mites are a type of biological control agent used in many countries against various vegetable pests, particularly spider mites. Despite the significant presence of predatory mites in the Tibetan plateau, there is limited research on their fitness and prey capacity in the area. Herein, four predatory mite species, including one species Neoseiulus californicus and three species from genus Amblyseius (Amblyseius swirskii, Amblyseius barkeri, and Amblyseius cucumeris) were investigated. Specifically, their fitness and prey capacity on two-spotted mites (Tetranychus urticae) at highland conditions were evaluated. Compared to the other three predatory species, A. swirskii had the highest fecundity (Mean ± SEM=11.60 ± 0.34) and the highest pre-adult survival rate (Mean ± SEM = 83.33 ± 3.33%). Since their juvenile Survival Rate (SR) was extremely low (Mean ± SEM =13.33% ± 5.77%), most A. barkeri nymphs died before emergence. Compared to the other three predatory mites, A. swirskii had the highest predation capacity on T. urticae adult mites at 15 d post-release (Mean ± SEM =14.28 ± 2.24). Collectively, these findings imply notable advantages in employing A. swirskii for controlling two-spotted mites in the Tibetan Plateau. Furthermore, based on the results, A. swirskii was the most effective, and A. barkeri was the least effective in controlling two-spotted mites in the Tibetan Plateau. These findings could inform the development of a feasible biological control method based on suitable predatory mite species to manage T. urticae in the Tibetan Plateau, and would be helpful in delaying the rise or emergence of chemical pesticide resistance in two-spotted mites.

Elovanoids (ELV) are novel lipid mediators synthesized from very long-chain (VLC) omega-3 (n-3) polyunsaturated fatty acids (PUFA), particularly docosahexaenoic acid (DHA) or eicosa-pentaenoic acid (EPA), by the elongase enzyme ELOVL4. ELV have been shown to play a funda-mental role in maintaining brain and retina function, neuroprotection, maintaining the skin's permeability barrier, and sperm function, among other important cellular processes. Furthermore, the methyl ester or sodium salt of ELV-N32 and ELV-N34 have been found to be efficient in re-duced infarct volumes, promoting cell survival and decreasing the alteration of the neurovascular unit in a model of ischemia due to occlusion of the middle cerebral artery. Their bioactivity in-cludes enhancing of anti-apoptotic and pro-survival protein expression combined with the downregulation of pro-apoptotic proteins. House dust mite (HDM) is the most prevalent indoor allergen, and HDM exposure is frequently the cause of allergic respiratory disease, including aller-gic rhinitis and allergic asthma in HDM sensitized individuals. In our study, human nasal epithe-lial cells (HNEpC) were used as an in vitro model for allergy. The cells were challenged with HDM (mixture of Dermatophagoides farinae and D. pteronyssinus extract), with or without treat-ment with ELV-34. Phosphate-buffered saline (PBS) (vehicle) and ELV-34 (500 nM) alone were used as the control. Our findings show that ELV-34 promotes cell viability and reduces cytotoxi-city upon HDM sensitization of HNEpC. ELV-34 treatment significantly reduces the levels of IL-6, IL-1β, IL-8, VEGF, ICAM1, CXCL1 and CCL2, restored the IL-10 level and diminishes the induc-tion of the transcription of inflammatory and senescence genes in HNEpC. Our data also shows that HDM triggered the expression of several key genes in human nasal epithelial cells, including autophagy, unfolded protein response (UPR), Matrix metalloproteinases (MMPs), senescence and inflammation markers. Together, our data reveal a novel pro-homeostatic and cell-protective li-pid-signaling mechanism in nasal epithelial cells that envision novel potential therapeutic targets for the treatment of allergies.

Neonicotinoids, such as dinotefuran (DF), have caused a variety of problems, such as massive loss and winter failure of the bee colony, as a price for the benefit of reducing farm work, because it continues to maintain a high insecticide activity over a long period of time. In this study, a field experiment was conducted for about six months to investigate the effects of DF on bee colonies damaged by Varroa mites. This study examined the long-term changes in such as the size of bee colonies, the intake of sugar syrup (SS), intake of pollen paste (PP), which is a vehicle for administering DF, the intake of DF, the mite-prevalence of bees and the inside and outside temperatures of hive-boxes. The variation width of the inner temperature of the hive-box is less than that of the ambient temperature (Ta). The inner temperature of the hive-box is adjusted with about 30 ℃ of Ta as the boundary. If Ta is lower than 30 ℃, the inner temperature of the box is higher than Ta, and if Ta is higher than 30 ℃, it is lower than Ta. The temperature variation width of the DF-exposed colony is greater than that of the control colony. The average intake of SS per bee per day of the DF-exposed colony is more than that of the control colony. The average intake of PP per bee per day of the DF-exposed colony is almost equal to that of the control colony. These results suggest that bees do not avoid DF, and ingest PP without distinction between toxic and pesticide-free. In the period from the start of DF administration to the colony extinction, the intake of DF per colony is about 865 µg/colony, the intake per bee is 14 ng/bee, and the intake per bee per day is less than 0.1 ng/bee/day in this work. These intakes are much lower than the previous ones (60-65 ng/bee, 0.27-2.32 ng/bee/day). These discrepancies may be because attacks of mites and Japanese giant hornets hastened the colony collapse. Seasonal changes in mite-prevalence of honeybees is approximately the same regardless of the bee colonies. At the end of August (the start of attacks by Japanese giant hornets), the mite-prevalence will increase rapidly. Even if the number of bees damaged by mites turns to decrease, the mite-prevalence will continue to increase, with approaching 100% before bee colonies become extinct. In this study, it was found that the bee colony was collapsed by the intake of a smaller amount of DF due to the synergistic effect of DF and mite-damage. To prevent a bee colony collapse, not only to make an effort to minimalize the adverse effect on the bee colony of neonicotinoids such as DF with long-term residual effect and high insecticide properties, it is necessary to reduce the damage of mites as much as possible, while considering the synergistically adverse effects of neonicotinoids and miticides.

In the current context of worldwide honey bee colony losses, among which the varroa mite plays a major role, hope to improve honey bee health lies in part in the breeding of varroa resistant colonies. To do so, methods used to evaluate varroa resistance need better understanding. Repeatability and correlations between traits such as Mite Non-Reproduction (MNR), Varroa Sensitive Hygiene (VSH) and hygienic behaviour are poorly known, due to practical limitations and to their underlying complexity. We investigate (i) the variability, (ii) repeatability of the MNR score and (iii) its correlation with other resistance traits. To reduce the inherent variability of MNR scores, we propose to apply an Empirical Bayes correction. On the short-term (ten days) MNR had a modest repeatability of 0.4 whereas on the long- term (a month) it had a low repeatability of 0.2, similar to other resistance traits. Within our dataset there was no correlation between MNR and VSH. Although MNR is amongst the most popular varroa resistance estimates in field studies, its underlying complex mechanism is not fully understood. Its lack of correlation with better described resistance traits and low repeatability suggest that MNR need to be interpreted cautiously, especially when used for selection.

The parasitic mite, Varroa destructor, has shaken the beekeeping and pollination industries since its spread from its native host, the Asian honey bee (Apis cerana), to the naïve European honey bee (A. mellifera) used commercially for pollination and honey production around the globe. Varroa is the greatest threat to honey bee health. Worrying observations include increasing acaricide resistance in the varroa population and sinking economic treatment thresholds, suggesting that the mites or their vectored viruses are becoming more virulent. Highly infested weak colonies facilitate mite dispersal and disease transmission to stronger and healthier colonies. Here, we review recent developments in the biology, pathology and management of varroa, and integrate older knowledge that is less well known.

Tetranychid outbreaks have been detected since 2016 in southern highbush blueberries (SHB); however, it was not until 2019 when the southern red mite (SRM), Oligonychus ilicis (Acari: Tetranychidae) was confirmed as the pest causing severe bronzing and stunting, in multiple Florida and Georgia commercial blueberry plantings. There is little known about the management of SRM in SHB and only three miticides (fenazaquin, fenpyroximate, and acequinocyl), have recently been registered for use in SHB between 2019 and 2020. Similarly, there is no knowledge regarding the existence of natural enemies of SRM in SHB. This is the first report of naturally occurring predatory mites (Amblyseius sp. and Neoseiulus ilicis) associated with SRM in SHB. Predatory mites were recorded in treated bushes after evaluating the performance of seven miticides used to manage SRM populations including spiromesifen, acequinocyl, sulfur, sulfur + molasses, bifenazate, fenpyroximate, and fenazaquin. Miticide efficacy was rated based on the number of SRM recorded on collected leaves and plant damage ratings using an arbitrary index (from 0= no bronzing to 4= 100% bronzing). Additionally, the presence or absence of predatory mites per sample was recorded. Fenpyroximate used as the standard miticide, significantly reduced mite numbers seven days after application, as well as acequinocyl and fenazaquin. Only plants treated with fenpyroximate or fenazaquin showed significantly less bronzing compared with the control plants. Overall, fenpyroximate and fenazaquin demonstrated the best performance for managing O. ilicis on SHB and safe to naturally occurring predatory mites. Lastly, the level of growers’ awareness regarding SRM was assessed using surveys in 2020 to design adequate educational materials available to the grower community.

Phytoseiidae inhabit a wide range of herbs, shrubs and trees. Aesculus hippocastanum is an important ornamental tree in Europe and is likely reservoir of these mites. We therefore assessed the species composition and the spatial and seasonal variability in the abundance of Phytoseiidae in city parks in South Bohemia, Czech Republic. Leaf samples were randomly collected from horse chestnut tree branches at eight sites, five times during the vegetation season in 2013. The mites were collected by washing technique and mounted on slides for identification. In total, 13,903 specimens of phytoseiid mites were found, and eight species were identified: Amblyseius andersoni, Euseius finlandicus, Kampimodromus aberrans, Neoseiulella tiliarum, Phytoseilus macropilis, Paraseiulus talbii, Paraseiulus triporus and Typhlodromus (Typhlodromus) pyri. Paraseiulus talbii and P. macropilis were recorded on the leaves of horse chestnut trees for the first time in the Czech Republic in this study. The predominant species was E. finlandicus (96.25%). The number of mites per compound leaf was, on average, 2.53, 10.40, 23.54, 11.59 and 9.27 on the sampling dates in each month between May and September, respectively. The mite density was significantly affected by the sampling site and date.

Varroa destructor is considered one of the most devastating parasites of the honey bee, Apis mellifera, and a major problem for the beekeeping industry. Currently, the main method to control Varroa mites is the application of drugs that contain different acaricides as active ingredients. The pyrethroid tau-fluvalinate is one of the acaricides most widely used in beekeeping due to its efficacy and low toxicity to bees. However, the intensive and repetitive application of this compound produces a selective pressure that, when maintained over time, contributes to the emergence of resistant mites in the honey bee colonies, compromising the acaricidal treatments efficacy. Here we studied the presence of tau-fluvalinate residues in hives and the evolution of genetic resistance to this acaricide in Varroa mites from honeybee colonies that received no pyrethroid treatment in the previous four years. Our data revealed the widespread and persistent tau-fluvalinate contamination of beeswax and beebread in hives, an overall increase of the pyrethroid resistance allele frequency and a generalized excess of resistant mites relative to Hardy-Weinberg equilibrium expectations. These results suggest that tau-fluvalinate contamination of the hives may seriously compromise the efficacy of pyrethroid-based mite control methods.

A two-year study was conducted in Maine wild blueberry fields (Vaccinium angustifolium Aiton) on the health of migratory honey bee colonies in 2014 and 2015. In each year 3-5 colonies were monitored at each of 9 wild blueberry field locations during bloom (mid-May until mid-June). Colony health was measured by assessing percent worker and sealed brood rate of change from the beginning of bloom until the end of bloom. Potential factors that might affect colony health were queen failure or supersedure; pes-ticide residues on trapped pollen, wax comb, and bee bread; and parasites and pathogens. We found that Varroa mite and pesti-cide residues on trapped pollen were significant predictors of colony health as measured by the percent rate of change of sealed brood during bloom. These two factors explained 71% of the variance in colony health over the two years. Pesticide exposure was different in each year as were pathogen prevalence and incidence. We detected high prevalence and abundance of two recently discovered pathogens and one recently discovered parasite, the trypanosome Lotmaria passim Schwartz, the Sinai virus, and the phorid fly, Apocephalus borealis Brues.

The post-hoc analysis presented here aimed to address the influence of endogenous vitamin D in the immunological mechanism underlying effective mite allergoid-immunotherapy (AIT). Previously, we have shown that one subpopulation of T regulatory cells results in phenotypically identifiable as functionally potentiated and memory cells in allergic children after 12 months of this immunoactive treatment. Indeed, AIT is the only known treatment able to reshape the detrimental immune response against the allergen into a not noxious one. Besides, VD is widely considered an immunoregulatory molecule endogenously produced and exogenously provided with foods and supplements that might interact with AIT mechanism and affect its outcome. Therefore, a post-hoc analysis of the clinical and immunological data of three different cohorts of allergic patients was performed. One cohort (N=70) was on standard symptoms-controlling pharmacological treatment while the other two (N=60 and N=35, respectively) were treated with AIT for 12 months. Among the first were observed a lower mean endogenous VD level (<22 ng/ml) along with worse symptoms and higher use of medications. Remarkably, the comparison between two sub-cohorts of patients with serum VD above (N=32) or below (N=28) a cut-off value set at mean value (27 ng/ml) revealed that optimal improvement of all clinical and immune parameters was achieved (as expected by effective AIT), irrespective of the VD level. Notably, the third analysis, carried out on one cohort of AIT patients also taking concomitantly VD3 as food supplement (N=19), was distinguished by uppermost overall treatment outcome (amelioration of symptoms, lowest medications requirement, and reduction of total and allergen-specific IgE) as well as the increase of allergen-specific tolerogenic memory T regulatory cells. These findings suggest that endogenous VD level affects allergy severity and allergen immunotherapy effectiveness. Also, VD3 might be investigated as an add-on supplement to get the best out of immunotherapy in VD deficient/insufficient allergic patients. The immunogenic but low-allergenic mite allergoid used as bioactive agent might have contributed to minimize allergic and highlight immunological effects described here.