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The two-spotted spider mite, Tetranychus urticae Koch, has a broad host plant range and presents an extreme capacity for developing pesticide resistance, becoming a major economic pest in agriculture. Anticholinesterase insecticides still account for a big part of global insecticide sales. However, there is a growing concern about the serious resistance problems of anticholinesterase insecticides and their nontarget toxicity. In this study, structure-based virtual screening was performed to discover selective AChE inhibitors from the ChemBridge database, and 39 potential species-specific AChE inhibitor were obtained targeting T. urticae AChE, but not human AChE. Among them, compound No. 8 inhibited AChE from T. urticae , but not from human, and had an inhibitory activity comparable to that of eserine. Compound No. 8 had dose-dependent toxicity to T. urticae in glass slide-dipping assay and had significant mite control effects in a pot experiment, but required a high concentration to achieve similar control effects to spirodiclofen. The toxicity evaluation suggested that compound No. 8 had no acute toxicity on pollinator honey bees and natural predator N. californicus and did not affect strawberry growth in our assay. Compound No. 8 is a potential lead compound for developing novel acaricides with reduced nontarget toxicity. [ABSTRACT FROM AUTHOR]

Tetranychus urticae is a worldwide common pest for many vegetable species in greenhouses and open fields. The study was conducted to evaluate the performance of two acaricide mixtures: Highpoint® 10% EC (abamectine + hexythiazox) and Ignar® 20% SC (abamectine + spirodiclofen), as well as a single active ingredient, Envidor® 24% SC (spirodiclofen), against the two-spotted spider mite in greenhouse and lab experiments. In the greenhouse experiment, both Ignar® and Highpoint® outperformed Envidor® acaricide against the adult and immature stages through the first 3 days in both experimental seasons. After 24 hours, Ignar® and Highpoint® achieved the highest efficacy with percent of reduction 95.00 and 94.86 in the 1st season and 97.84 and 95.76% in the 2 nd season, respectively. Meanwhile, Envidor® gave lower reduction percentages of 84.93 and 83.88%, respectively. Regarding the immature stage, Ignar®, Highpoint®, and Envidor® achieved reductions of 95.63%, 94.26%, and 83.31% after 24 hours for the first season and 94.09, 95.79, and 80.57% in the second season, respectively. The residual efficacy gradually decreased to reach 62.22 and 59.72% for Ignar® and 58.31 and 59.31% for Highpoint® in both seasons. On the other hand, the initial kill for all acaricides against the egg stage was low after 24 hours. However, after 3 days, Ignar® and Highpoint® showed a sharp increase in efficacy, with a reduction percent (81.24 and 51.60% in the 1st season) and (73.83 and 81.86% in the 2nd season), respectively. Envidor® showed high efficacy only at the 7th day, with varying efficacy during the inspection periods. Laboratory bioassay tests revealed that Ignar® was the most toxic acaricide against T. urticae adults and immatures, with a 100% toxicity index. Highpoint® had a moderate toxicity index against adult and immature stages, while Envidor® was less effective. Ignar® and Highpoint® were the most toxic compounds against eggs. Abamectin mixtures are the most toxic compounds. Highpoint® and Ignar®, were considered to have the best efficacy on all developmental stages of the two-spotted spider mite. Due to the extensive use of abamectin to eliminate mites and numerous sucking insects, it is better to avoid its repeated use alone or in the same mixtures to control mites for more than one or two applications in the season. The data may suggest that the appropriate acaricide for integrated pest management (IPM) for all stages of T. urticae could be Ignar® and Highpoint®. [ABSTRACT FROM AUTHOR]

The acaricides tested for their efficacy against Tetranychus urticae Koch infesting okra under field conditions during summer 2022 revealed that all the acaricides were significantly superior over untreated control in checking the spider mite population. Among the acaricides fenazaquin 10 EC @ 125 g a.i./ha was found to be most effective in controlling the spider mite, T. urticae. On the basis of effectiveness (% reduction), the descending order was Fenazaquin 10 EC @ 125 g a.i./ha (51.83%) > fenpropathrin 10 EC @ 30 g a.i./ha (46.12%) > Buprofezin 25 EC @ 150 g a.i./ha (45.26%) > Fenpyroximate 5 EC @ 30 g a.i./ha (43.14%) > Spiromesifen 240 SC @ 100 g a.i./ha (41.32%) > Propargite 57 EC @ 570 g a.i./ha (38.71%) > chlorfenapyr 10 EC @ 75 g a.i./ha (37.21%) > Diafenthiuron 50 WP @ 300 g a.i./ha (36.78%) > Hexythiazox 5.45 EC @ 25 g a.i./ha (35.24%) > water spray (17.58%). [ABSTRACT FROM AUTHOR]

In recent years, the utilization of biocontrol agents to administer agriculture pests has received more attention, which has conduce to an growth in companies generating biocontrol agents, including predators and parasitoids. Amblyseius swirskii Athias-Henriot as a part of predatory communities in greenhouses is currently used worldwide as a biocontrol agent against small insects and various mites, especially to suppress the population of the two-spotted spider mite (TSSM), Tetranychus urticae Koch. To improve mass rearing of A. swirskii and optimize its application in integrated pest management programs, its development rate was determined at seven constant temperatures ranging from 15 to 34 (±1)°C, 50±10% RH and a photoperiod of 16:8 (L:D) h under laboratory conditions. None of the eggs hatched at 34°C and no development was observed. To determine the lower temperature threshold (T0) and thermal constant (K) of different stages of the predator, two linear models (ordinary and Ikemoto) were used. In addition, 26 nonlinear models were fitted to evaluate the development rate at different temperatures. The lower temperature threshold (T0) and thermal constant (K) of total immature stages were estimated by the ordinary (3.72°C and 133.22 DD) and Ikemoto (10.64°C and 86.51DD) linear models. Based on the Akaike information criterion (AIC), the best model for the description of the temperature-dependent development rate of the egg, larval, protonymphal, and dutonymphal stages was the Ratkowsky model and for the whole pre-adult stage, it was the Logan-6 model. Our results provided a detailed evaluation of the thermal requirements of A. swirskii, which can be important in improving the role of this mite in biological control programs. [ABSTRACT FROM AUTHOR]

Six-spotted mite, Eotetranychus sexmaculatus (Riley), is an introduced pest of 'Hass' avocados in New Zealand. Avocado orchards were surveyed for six-spotted mite and its natural enemies during 2016–18. Mean counts of six-spotted mite differed when compared by year. For each year, the effect of not spraying or spraying according to an integrated pest management programme (AvoGreen®) was not consistent for most location and season combinations. When year was ignored and all locations considered together, the leaves of unsprayed trees had fewer six-spotted mites than those of sprayed trees during autumn/winter. The phenology of mites and their predators in relation to leaf abscission was also determined on unsprayed potted trees during 2018–20 at two sites. Defoliation occurred in October and November each year but the association with densities of six-spotted mites was not consistent. Four species of phytoseiid mite predators were identified on orchards and potted trees with the most common species being Amblyseius herbicolus. The coccinellid mite predators Stethorus bifidus and S. histrio occurred on potted trees. The evidence that predators were able to control six-spotted mite populations was somewhat equivocal. Trials comparing sprayed and unsprayed trees under the same nutrient management and during multiple seasons would be useful. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of the College Of Basic Education is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Honey bee colony management is critical to mitigating the negative effects of biotic and abiotic stressors. However, there is significant variation in the practices implemented by beekeepers, which results in varying management systems. This longitudinal study incorporated a systems approach to experimentally test the role of three representative beekeeping management systems (conventional, organic, and chemical-free) on the health and productivity of stationary honey-producing colonies over 3 years. We found that the survival rates for colonies in the conventional and organic management systems were equivalent, but around 2.8 times greater than the survival under chemical-free management. Honey production was also similar, with 102% and 119% more honey produced in conventional and organic management systems, respectively, than in the chemical-free management system. We also report significant differences in biomarkers of health including pathogen levels (DWV, IAPV, Vairimorpha apis, Vairimorpha ceranae) and gene expression (def-1, hym, nkd, vg). Our results experimentally demonstrate that beekeeping management practices are key drivers of survival and productivity of managed honey bee colonies. More importantly, we found that the organic management system—which uses organic-approved chemicals for mite control—supports healthy and productive colonies, and can be incorporated as a sustainable approach for stationary honey-producing beekeeping operations. [ABSTRACT FROM AUTHOR]

All agricultural workers must know the main pest that affect their crops to prevent their attacks or take appropriate action as soon as they appear. The objective of this work was to know the perception of the agricultural workers of the "La Rosita" farm on the incidence of pest mites and their control. For this, a semi-structured survey was applied. The data were processed using Microsoft Excel© 2016 electronics spreadsheets and were analyzed through descriptive statistics, determining the frequencies of appearance of the responses. It was found that 80 % of those surveyed are aware of pest mites, with a higher presence of Polyphagotersonemos latus and Tetranychus tumidus in peppers, tomatoes and beans, although between 10 and 20 % found these pests in cabbage, corn and onion that shows little knowledge in relation to its identification. The 80 % of agricultural workers choose chemicals using sulfur, dicofol and Mitigan CE 18.5 more frequently. The 20 % of agricultural workers are aware of some plant extracts that are used and 100 % are unaware of the biological controls that can be used, including predatory mites. This infers that this topic constitutes one of the main training needs for agricultural workers on the farm [ABSTRACT FROM AUTHOR]

BACKGROUND: Ripened cheeses, such as pecorino, are susceptible to mites and molds contamination on the crust area that must be removed before the product can be marketed. This study investigates the effectiveness of gaseous ozone treatment in the control of microbiological and mite growth without negatively affecting product quality. RESULTS: Cheese samples were treated with gaseous ozone at 200 and 300 ppb for 8 h per day (overnight) for 150 days in storage rooms under controlled conditions (12 °C and 85% relative humidity). The results showed that ozone at 200 ppb limits the growth of mites starting from 25 days of storage and significantly reduced bacteria, molds, and yeasts counts starting from 75 days of storage. Concerning the physicochemical and qualitative parameters evaluated during ripening (weight loss, moisture content, dry weight, ash, fat, protein, total nitrogen, color, non‐destructive firmness), no significant differences were shown between the control samples and ozone treatment at 200 ppb. Sensory analysis (consumer test) also showed no specific defects with the ozone‐treated samples. It was observed that the ozone treatment at 300 ppb had limited microbiological growth and no alteration of sensory aspects but did not have the same positive impact on some aspects of overall quality, compared with ozone treatment at 200 ppb. CONCLUSION: The use of gaseous ozone treatments during ripening of pecorino cheese can potentially offer an excellent solution for the control of mite growth, while preserving the quality and sensory characteristics of the product. For this reason, this technique could be very useful for commercial purposes. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The Persea mite, Oligonychus perseae Tuttle, Baker & Abbatiello (Acari: Tetranychidae), is an economically important foliar pest of avocados in Spain. The effects of this mite on the foliar damage, production losses and economic impact were assessed in two avocado, cv. Hass, orchards located in the main growing areas of Spain (Northern Tenerife and Málaga) for 3 and 5 consecutive years, respectively. The economic injury level (EIL) for the optimization of the use of acaricides to control this mite was also established, considering three spraying strategies: (i) mite-free treatment (<50 mites per leaf), (ii) conventional treatment (50–150 mites per leaf), and (iii) control treatment (the absence of spraying). Persea mite populations were sampled fortnightly and foliar damage was estimated. At the end of each season, fruits were harvested, weighed and production losses were quantified. The cumulate mite-days (CMDs) had a significant effect on the percentage of leaf area damaged (PLAD) and yield reduction. High numbers of the Persea mite caused extensive damage to leaves, so a loss in tree yield was evident. However, for the middle population level, there was no evidence of yield losses. The quantitative EIL was estimated at a PLAD of 17%, equivalent to a CMDs of 178 mites per leaf, which is the amount of damage that should not be exceeded. In Northern Tenerife, with a mild climate, the Persea mite can reach significant populations that are maintained throughout the months. In avocado orchards in Málaga, the summer is hotter and drier, so the presence of the mite exists for a shorter duration in the seasons, with less damage to the leaves. In Tenerife, yield loss can be compensated by chemical treatments that permit pest control. [ABSTRACT FROM AUTHOR]

Simple Summary: Panonychus ulmi is a pest of several agriculturally important crops, including apples. If populations are not controlled, it can cause severe foliar damage in apple that results in lower return bloom and yield loss in following year. Biological mite control of this pest can be achieved in eastern United States apple orchards if growers conserve several species of predatory mites through proper selection and timing of insecticide applications for the main pests such as codling moth which directly damage the fruit. When apple growers occasionally loose biological mite control, they need to rely on effective miticides that also conserve these predatory mite species to maintain sustainable pest mite control. Efficiency of different pesticide chemicals used for the P. ulmi management and their non-target effects on predatory mites conserved for biological mite control in apple orchards are discussed. Panonychus ulmi (Koch) (Acari: Tetranychidae), commonly known as European red mite, is a polyphagous pest of various tree and small fruit crops, including apples. A field study was conducted to evaluate different pesticide options available for the management of P. ulmi, and their impact on the population of non-target predatory mite species complex consisting of Neoseiulus fallacis, Typhlodromus pyri, and Zetzellia mali in apple orchards. Pesticides were applied using a commercial airblast sprayer at the 3–5 mite/leaf recommended economic Integrated Pest Management (IPM) threshold or prophylactically in the spring ignoring IPM practices such as monitoring, reliance on biological control and economic thresholds. Effects on the motile and egg stages of P. ulmi were evaluated as were effects on the populations of predatory mites through frequent leaf counts during the season. We also recorded the subsequent overwintering eggs of P. ulmi from each pesticide treatment. The two prophylactic treatments containing a mixture of zeta-cypermethrin + avermectin B1 + 1% horticultural oil and abamectin + 1% horticultural oil provided effective control of P. ulmi population throughout the season without reducing predatory mite populations. In contrast, eight treatments applied at the recommended economic threshold of 3–5 mites/leaf were not effective in suppressing P. ulmi populations and most reduced predatory mites. Etoxazole had significantly higher number of overwintering P. ulmi eggs compared to all other treatments. [ABSTRACT FROM AUTHOR]

Agriculture is the most important economic activity around the world with its contributions reflected by its share in the gross domestic product of countries. It ensures food security, provides raw materials for many industries and employment opportunities. Today, pest and diseases are among the main challenges plaguing the agricultural sector. More specifically, phytophagous mites are devastating many economically important crops worldwide. Tetranychus urticae Koch (Two-spotted spider mites), Raoiella indica Hirst, (red palm mites), Polyphagotarsonemus latus Banks (broad mites) and Panonychus ulmi Koch (European red mites) are widely known for their extensive damage to crops. To control these mites, farmers have incorporated the use of pesticides into their farming systems. However, chemical control comes with many problems such as insect resistance, detrimental environmental effects and various human health implications. As such biological control is an environmentally friendly alternative that uses bio-control agents such as predators, pathogens and parasitoids to control pests. In this review, it was found that predators and pathogens were the most widely used biocontrol agents, specifically, the Amblyseius spp. Berlese were most effective and widely documented. The available literature also suggests that for successful control of agricultural mites via biological control, there needs to be a clear understanding of the behaviors of these mites and the bio-control agents used. [ABSTRACT FROM AUTHOR]

The assessment of the long-term negative effects of acaricides on the target and non-target mites can help determine the toxicity and side effects of acaricides. The sublethal concentrations can be very precise and affect populations at concentrations lower than the conventional concentration and may supplement our knowledge about its sublethal effects on the physiology and behavior of insects/mites. Furthermore, we exposed the adults' biocontrol agents mite, Phytoseiulus persimilis Athias-Henriot and Neoseuilus californicus McGregor, to the LC10 and LC30 concentrations of the Cyflumetofen and then assayed the effects of these concentrations on the growth and development of the next generations under laboratory conditions. Analyzed data showed that sublethal concentrations of cyflumetofen significantly affected both species' biological parameters, including the total lifetime, fecundity, and longevity of the treated biocontrol agents compared with the control treatment. Due to our results, when P. persimilis and N. californicus adults were exposed to LC30 concentration of cyflumetofen, the length of the oviposition period of the treated P.persimilis and N. californicus were 20.34 and 19.66 days, respectively. At the same time, these values for the control-treated P. persimilis and N. californicus were 22.51 and 22.21, respectively. The intrinsic rate of increase (r) in control were 0.203 and 0.238, while those treated with LC10 and LC30 of cyflumetofen were estimated to be 0.238 and 0.214 for P. persimilis and 0.203 and 0.223 days–1, for N. californicus, respectively. Therefore, using sublethal concentrations of cyflumetofen is emphasized for designing integrated pest management programs and makes it possible to use biocontrol agents to control the spider mite; thus, it would benefit the farmers and consumers in the long run. [ABSTRACT FROM AUTHOR]

The global spread of the parasitic mite Varroa destructor instigated a substantial decline in both managed and feral honeybee (Apis mellifera) colonies mainly across the Northern hemisphere. In response, many beekeepers began to treat their colonies with chemical acaricides to control mite populations in managed colonies. However, some countries or beekeepers allowed their bees to develop mite-resistance by adopting a "treatment-free" approach, rather than using selective breeding programs. Yet, the distribution and proportion of beekeepers either treating or not within the United Kingdom (UK) is unknown, as it is in most Northern hemisphere countries. Therefore, the aim of this study was to conduct a beekeeper survey to determine the current treatment strategies within the UK. We gathered 2,872 beekeeper responses from an estimated 30,000 UK beekeepers belonging to 242 bee-associations in the winter of 2020/21. The survey indicated that the majority (72–79%) of UK beekeepers are still treating their bees for Varroa, typically twice-yearly using chemical-based methods. Six percent or 1,800 UK beekeepers were treatment-free for six years or more. This is reflected by our finding that 78 associations out of 242 consist of responders who entirely treated, while only four associations had more than 75% of their members that were non-treating. Overall treatment status was not affected by association currently. Using the baseline data from this survey it will be possible in the future to observer if a shift towards treatment-free beekeeping occurs or not. [ABSTRACT FROM AUTHOR]

Dermanyssus gallinae, a parasitic mite that subsists on the avian blood of chickens, poses a considerable threat to the poultry industry. D. gallinae infestation can result in a plethora of detrimental effects for the host birds, including decreased egg production and anemia. Pyrethroid pesticides have been the primary means of combating this issue and have demonstrated high levels of efficacy. However, in recent years, D. gallinae has exhibited resistance to these chemicals, resulting in a marked decrease in their mortality; thus, an integrated control strategy in addition to the chemical use should be required for the sustainable control of this mite. This study confirms that D. gallinae can be effectively controlled through the utilization of high-voltage impulse discharges and that various electrical parameters possess optimal values that are required for mite control. The alterations in the body surface of the mite caused by high-voltage impulses were akin to those caused by heat, but no alteration in the elemental composition of the body surface was observed, suggesting a change in organization caused by currents flowing inside the exoskeleton. Comparatively, the mite control efficacy of high-voltage impulse was found to be substantially superior to that of ultraviolet light or ozone, with up to 95% more mites being killed in as little as 30 seconds. [ABSTRACT FROM AUTHOR]

The soil mesofauna comprises a group of arthropods, whose body size ranges from 0.2 to 2.0 mm, and which are important in transforming soil organic matter, recycling nutrients, and improving physical properties of the ground. Within the faunal groups that inhabit the soil, oribatid mites and springtails stand out because of their number, diversity, abundance of species and activity; great aptitude for speciation, short life cycle and little dispersion of species adapted to edaphic life and to different types of soils. Due to these characteristics, these organisms are used as biogeographic-ecological indicators and indicators of the soil quality and health. The use of biochar (Biocarbón in Spanish), as a soil amendment, to improve fertility and mitigate climate change is becoming a common practice. Rice husk biochar was used in three concentrations. Four tomato seedlings (Solanum lycopersicun L.) cultivar L43 were placed in each experimental unit. A composite sample of each treatment was taken weekly and placed in Berlese-Tullgren funnels for seven days. Subsequently, the collected samples were examined under the stereomicroscope and the individuals were separated by morphospecies for their subsequent slide mounting and identification. Arthropods belonging to the groups Insecta (Hymenoptera, Hemiptera, Coleoptera, Lepidoptera), Acari, and Collembola were identified. An increase in the number of Collembola was observed in the treatment with 75% Biochar (rice husk) after 28 days. In the case of mites, the most represented orders were Oribatida (Cryptostigmata), Prostigmata, and Mesostigmata, with an increase in their populations in the containers with 25% Biochar after 28 days. A positive influence of biochar on soil arthropods was demonstrated, expressed by the increase in the number of springtails and soil mites with respect to the control, with an outstanding recovery of soil biological activity in the short term. [ABSTRACT FROM AUTHOR]

RNAi has great potential as a novel strategy to control spider mite pests without targeting natural control agents such as predatory mites. To achieve this, an efficient RNAi target gene for spider mite control must also be ineffective against non-target predatory mites. Several genes obtained through horizontal gene transfer (HGT) have been shown to facilitate the adaptation of spider mites and thus fit the requirement of specific RNAi targets; however, comprehensive analyses of HGT genes in spider mites are still rare. Here, we identified and investigated the potential of HGT genes as RNAi targets in a key spider mite, Panonychus citri. A total of 78 HGT genes were identified with no evidence of homology in predatory mites. RNAi of six selected genes resulted in significant mortalities ranging from 50.7 to 68.5%, with RNAi of intradiol ring cleavage dioxygenase 1 (PcIDR1) resulting in the highest mortality. To test the specificity of HGT genes as RNAi targets, we predicted the off-target sites of PcIDR1 in the predatory mite Neoseiulus barkeri and tested their response to dsPcIDR1. Ingestion of dsPcVATPase, a commonly used RNAi target, but not dsPcIDR1 disrupted off-target genes and the predatory response of N. barkeri. In conclusion, our study demonstrates that HGT genes can serve as natural and specific RNAi targets for spider mite control without adverse effects on predatory mites. [ABSTRACT FROM AUTHOR]

Numerous lab and field studies have reported the potential of soil predatory mites for the biological control of plant-parasitic nematodes and arthropods pests. Most of these studies have utilized biocontrol agents in augmentative releases, essentially controlling the pest with the released predators. While this may be a valid approach, we hypothesize that conservation of soil mite predators with available, suitable, and accessible free-living nematodes as prey, will provide better agricultural ecosystem performance and long-range sustainability. In this manuscript, we review the relevant studies on soil predatory mite–nematode interactions and highlight their potential for conservation biological control of soil-borne pests. Additionally, we emphasize the importance of implementing environmentally sound soil management practices for the sustainability and conservation of functional soil food webs. [ABSTRACT FROM AUTHOR]

Contextualization: the poultry red mite (Dermanyssus gallinae) is an ectoparasite that affects the health, generates stress in the population, and decreases the growth rate of laying hens. Therefore, lowers the quality of the eggs. Knowledge gap: the control of D. gallinae is done with synthetic contact acaricides, but this parasite has generated resistance to them. That situation requires the development of studies to find novel and environmentally friendly alternatives to heal the hens. That is why essential oils have been proposed as an alternative, considering they have acaricidal activity depending on the composition of the oil, which is affected by genetic and environmental factors. Purpose: the objective of this research was to evaluate the acaricidal activity of the essential oil of T. vulgaris against D. gallinae of egg laying birds in Tinjaca (Boyacá - Colombia). Methodology: the essential oil of T. vulgaris, in concentrations of 0,05, 0,1, 0,15, 0,20 and 0,25 mg/cm², was evaluated through contact bioassays in laboratory conditions. Results and conclusions: 100% mortality of D. gallinae was obtained with the essential oil of T. vulgaris in concentrations of 0,05 and 0,25 mg/cm, at 35 minutes of contact. The lethal concentration [LC50] was 0,073 mg/cm and the lethal time [LT50] was 13 minutes. That proves that thyme essential oil can be an alternative for the control of the red mite in birds of poultry farms. [ABSTRACT FROM AUTHOR]

Natural acaricides are potential biorational mite control alternatives to conventional chemical acaricides. However, little is known about the molecular mechanism of defense response to natural acaricides in mites. We previously reported significant acaricidal properties of ethyl oleate (EO) against Tetranychus cinnabarinus (here referred to as a sibling species of two-spotted spider mite, Tetranychus urticae), a highly polyphagous pest devastating crops in fields and greenhouses worldwide. In this study, we explored the molecular responses of T. cinnabarinus exposed to EO using RNA-Seq and differentially expressed gene (DEG) analysis. A total of 131, 185, and 154 DEGs were identified in T. cinnabarinus after 1, 6, and 24 h of EO treatment. In addition, 36 putative detoxification-related DEGs, including 10 cytochrome P450s (P450s), three glutathione S-transferases (GSTs), nine UDP-glycosyltransferases (UGTs), eight esterases (ESTs), and six ATP-binding cassette transporters (ABC transporters), were identified. Interestingly, the upregulation of these detoxification-related genes might be the main defense response of T. cinnabarinus exposed to EO. A quantitative real-time PCR analysis indicated that the expression profiles of 19 random DEGs were consistent with the RNA-Seq results. These findings serve as valuable information for a better understanding of the acaricide-mite interaction and molecular mechanisms involved in the defense response of T. cinnabarinus against EO. [ABSTRACT FROM AUTHOR]

Simple Summary: The tomato russet mite (TRM), Aculops lycopersici (Eriophyidae), causes severe damage to tomato plants Lycopersicon esculentum, which results in a wilted, russetted appearance with desiccated leaves. This study focused on the search for a suitable biological control agent against TRM, as an alternative to commonly used sulfur or chemicals. The efficacy of several potential predatory mite species was assessed. Pronematus ubiquitus proved successful in preventing the development of TRM and damage symptoms. The potential of iolinid predatory mites for the biological control of eriophyids is discussed. Our search for a suitable biological agent to control the tomato russet mite (TRM), Aculops lycopersici, was initiated in 2013. Neoseiulus californicus, Amblyseius andersoni, and Neoseiulus fallacis showed a promising pest reduction potential in a curative control strategy. Although these beneficials had a low survival on tomato and were not able to eradicate the pest, plants did not present typical TRM damage. However, their inability to establish in the tomato crop means that their commercial use would require repeated introductions, making their use too expensive for growers. Other predatory mites in the survey, such as the iolinids Homeopronematus anconai and Pronematus ubiquitus, showed the potential for a preventative strategy as they can establish and reach high densities on tomato with weekly or biweekly provision of Typha angustifolia pollen as a food source. When the tomato crop was adequately colonized by either iolinid, the development of TRM and any damage symptoms could be successfully prevented. The potential of iolinid predatory mites for biological control of eriophyids is discussed. [ABSTRACT FROM AUTHOR]

A report of our earlier study described a phytoseiid mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) release system using a moisturized sheltered sachet for spider mite control. For the present study, we installed the predator release systems on 43 out of 71 trees in a Japanese pear orchard to survey the dispersal of N. californicus released from the predator release system. In the orchard, Japanese pear trees were trained on the overhead horizontal trellis system. Consequently, the trees were mutually connected through the trellis training system. We collected phytoseiid mites on the tree leaves and were subjected to PCR to examine their species composition. Results demonstrated that N. californicus were 62.37% of the total of 3,247 phytoseiid mites collected. Using microsatellite markers, commercialized N. californicus that had been released from the predator release systems were discriminated from indigenous N. californicus. Results demonstrated that phytoseiid mites consisting mainly of the commercialized N. californicus occurred one week earlier in trees with the predator release systems. Results also demonstrated that the commercialized N. californicus dispersal occurred mainly in trees installed with the predator release systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: The success of biological control using predators is normally assumed to be achieved through direct predation. Yet it is largely unknown how the predator‐ and killed prey‐induced stress to prey may contribute to biological control effectiveness. Here, we investigate variations in life‐history traits and offspring fitness of the spider mite Tetranychus ludeni in response to cues from the predatory mite Phytoseiulus persimilis and killed T. ludeni, providing knowledge for evaluation of the nonconsumptive contribution to the biological control of T. ludeni and for future development of novel spider mite control measures using these cues. RESULTS: Cues from predators and killed prey shortened longevity by 23–25% and oviposition period by 35–40%, and reduced fecundity by 31–37% in T. ludeni females. These cues significantly reduced the intrinsic rate of increase (rm) and net population growth rate (R0), and extended time to double the population size (Dt). Predator cues significantly delayed lifetime production of daughters. Mothers exposed to predator cues laid significantly smaller eggs and their offspring developed significantly more slowly but these eggs had significantly higher hatch rate. CONCLUSION: Predator‐ and killed prey‐induced fears significantly lower the fitness of T. ludeni, suggesting that these nonconsumptive effects can contribute to the effectiveness of biological control to a great extent. Our study provides critical information for evaluation of biological control effectiveness using predators and paves the way for identification of chemical odors from the predator and killed prey, and development of new materials and methods for the control of spider mite pests. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Spider mites cause substantial economic losses and are difficult to control in agricultural systems. Ginkgo biloba L. extract has potential as an acaricide, although its specific acaricidal components have yet to be identified. We used bioassay-guided isolation to isolate and purify three main ginkgolic acid (GA) compounds (C13:0, C15:1, and C17:1). Their chemical structures were identified as 1H, 13C, and IR, respectively. The LC 50 values of GA C13:0, GA C15:1, and GA C17:1 against Tetranychus cinnabarinus were 777.75, 481.07, and 180.25 μg mL−1, respectively, demonstrating high toxicity. The efficacies of 23% GA soluble liquid (SL) with a dosage of 1500 a.i. g·hm−2 after 14 days were 82.45% and 85.41%, respectively, in Dali County and Chengcheng County, Weinan, China. The GA extraction process was optimized using methanol as the extraction solvent, heating and refluxing at 60 °C for 4 h at a solid-liquid ratio of 1:4, and repeating the process twice. The GA extraction rate of G. biloba exocarp was 43.2%, and the total extraction content of the three main GA compounds was 68.73%. Our optimization of the GA extraction process from G. biloba exocarp has the potential to be applied on an industrial scale, and GAs could be used as a commercial acaricide for controlling mites in the future. [Display omitted] • Three GAs were isolated from G. biloba L. • A significant acaricidal activity of three GAs were determined. • 23% GA SL had remarkable control effect against carmine spider mite. • The extraction process of GAs from G. biloba L. was optimized. [ABSTRACT FROM AUTHOR]

The BEEHAVE model simulates the population dynamics and foraging activity of a single honey bee colony (Apis mellifera) in great detail. Although it still makes numerous simplifying assumptions, it appears to capture a wide range of empirical observations. It could, therefore, in principle, also be used as a tool in beekeeper education, as it allows the implementation and comparison of different management options. Here, we focus on treatments aimed at controlling the mite Varroa destructor. However, since BEEHAVE was developed in the UK, mite treatment includes the use of a synthetic acaricide, which is not part of Good Beekeeping Practice in Germany. A practice that consists of drone brood removal from April to June, treatment with formic acid in August/September, and treatment with oxalic acid in November/December. We implemented these measures, focusing on the timing, frequency, and spacing between drone brood removals. The effect of drone brood removal and acid treatment, individually or in combination, on a mite‐infested colony was examined. We quantify the efficacy of Varroa mite control as the reduction of mites in treated bee colonies compared to untreated bee colonies. We found that drone brood removal was very effective, reducing mites by 90% at the end of the first simulation year after the introduction of mites. This value was significantly higher than the 50–67% reduction expected by bee experts and confirmed by empirical studies. However, literature reports varying percent reductions in mite numbers from 10 to 85% after drone brood removal. The discrepancy between model results, empirical data, and expert estimates indicate that these three sources should be reviewed and refined, as all are based on simplifying assumptions. These results and the adaptation of BEEHAVE to the Good Beekeeping Practice are a decisive step forward for the future use of BEEHAVE in beekeeper education in Germany and anywhere where organic acids and drone brood removal are utilized. [ABSTRACT FROM AUTHOR]

Varroa mites are highly attracted to drone brood of honey bees (Apis mellifera), as it increases their chance of successful reproduction. Therefore, drone brood removal with trap frames is common practice among beekeepers in Europe and part of sustainable varroa control. However, it is considered labour‐intensive, and there are doubts about the effectiveness of this measure. At present, it is mostly unknown how many mites a drone frame can carry at different times of the season, and how many mites can be removed on average if this measure is performed frequently. Therefore, we sampled a total of 262 drone frames with varying proportion of capped cells (5–100%) from 18 different apiaries. Mites were washed out from brood collected from mid‐April to mid‐July based on a standard method to obtain comparable results. We found that a drone frame carried a median of 71.5 mites, and with the removal of four trap frames, about 286 mites can be removed per colony and season. In addition, mite counts were significantly higher in June and July than in April and May (Tukey‐HSD, P < 0.05). The number of mites and the proportion of capped cells, however, were not correlated (R2 < 0.01, P < 0.05). Our results suggest that drone brood removal is effective in reducing Varroa destructor numbers in colonies, supporting the findings of previous studies on the efficacy of this measure. Although mite counts varied, we believe that increasing sample size over different seasons and locations could elucidate infestation patterns in drone brood and ultimately improve drone brood removal as an integrated pest management tool for a wider audience of beekeepers. [ABSTRACT FROM AUTHOR]

Emaravirus (Order Bunyavirales; Family Fimoviridae) is a genus comprising over 20 emerging plant viruses with a worldwide distribution and economic impact. Emaraviruses infect a variety of host plants and have especially become prevalent in important long-living woody plants. These viruses are enveloped, with a segmented, single-stranded, negative-sense RNA genome and are transmitted by eriophyid mites or mechanical transmission. Emaraviruses have four core genome segments encoding an RNA-dependent RNA polymerase, a glycoprotein precursor, a nucleocapsid protein, and a movement protein. They also have additional genome segments, whose number varies widely. We report here that the proteins encoded by these segments form three main homology groups: a homolog of the sadwavirus Glu2 Pro glutamic protease; a protein involved in pathogenicity, which we named "ABC"; and a protein of unknown function, which we named "P55". The distribution of these proteins parallels the emaravirus phylogeny and suggests, with other analyses, that emaraviruses should be split into at least two genera. Reliable diagnosis systems are urgently needed to detect emaraviruses, assess their economic and ecological importance, and take appropriate measures to prevent their spread (such as routine testing, hygiene measures, and control of mite vectors). Additional research needs include understanding the function of emaravirus proteins, breeding resistant plants, and clarifying transmission modes. [ABSTRACT FROM AUTHOR]

Experiments assessed the comparative efficacy of oxalic acid solution (OA) and combination of formic acid (FA) evaporation and trickling OA to control the honey bee mite, Varroa destructor, at two apiary locations. Queen caging, consecutive OA treatments of broodless colonies, or combined treatments using OA and FA in colonies with brood increased mite mortality (P < 0.05) in comparison to the pre-treatment period. FA application in colonies with brood in September and October resulted in an average mite mortality of 18% in the first apiary and subsequent FA applications in the same period in the second apiary killed, on average, 73% and 71% of mites; respectively. OA treatment of broodless colonies after queen caging at two apiaries resulted in 18% and 47% mite mortality. Caging the queens and OA treatments in broodless colonies or subsequently use consecutive OA or FA treatments ensure adequate mite reduction before wintering the colonies. Synergistic control methods of Varroa mites using OA and FA along with queen caging is discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND: A spider mite control method using night‐time ultraviolet (UV)‐B irradiation was recently developed for strawberry greenhouses (UV method). The control effect of this UV method is negatively affected by increasing temperature. Tetranychus urticae eggs are more resistant to a single dose of UV‐B irradiation than Neoseiulus californicus eggs. By contrast, N. californicus can better survive nightly UV‐B irradiation with the UV method compared with T. urticae. To elucidate the mechanism underlying these phenomena, we explored the hypotheses that higher temperature promotes photoenzymatic repair (PER) and that mortality is determined by UV‐B susceptibility in the embryonic stage exposed to UV‐B. RESULTS: PER efficacy was not promoted by increasing temperature. The lowest hatchability (around zero) of T. urticae eggs after a single dose of UV‐B irradiation (0.288 and 0.432 kJ m−2) without photoreactivation was seen in the morphogenesis stages between "cleavage ended" and "eye points became colored". Based on these results, we developed a linear function of daily UV‐B irradiance and deviation of cumulative irradiance during vulnerable embryonic developmental phases from 50% lethal dose (LD50) after a single dose of UV‐B irradiation. The difference between T. urticae and N. californicus and changes in UV‐B vulnerability due to temperature could be explained by this simple relationship. CONCLUSION: Slower development in T. urticae than N. californicus in nature and developmental delay under low temperatures increase the ovicidal effects of the UV method. This shows the advantage of the simultaneous use of the UV method and biological control, contributing to the development of integrated pest management. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mass rearing herbivorous insects used as biological control agents requires a steady supply of optimal host plant material. This often necessitates the use of pesticides to minimise infestations and damage from generalist herbivores. Knowing the efficacy persistence of the pesticide is critical to prevent non-target effects on reared agent populations. We determined the amount of time for an abamectin foliar spray to degrade such that there were minimal impacts on the mass rearing of Pseudophilothrips ichini (Hood), a biological control agent for Brazilian peppertree (Schinus terebinthifolia Raddi) in Florida. Abamectin was applied to plants at the label concentration (0.31 ml/L) for controlling mites. Groups of three plants were brought into our quarantine facility 1, 3, 7, 10, and 14 d after application and were then each infested with 40 founding adult thrips. Founding adult survival was not impacted by the delay, i.e. interval between application and thrips infestation, with at least 75% recovered alive regardless of the delay. However, delaying infestation had a significant effect on the number of offspring produced, with, on average, only 50 produced when waiting 1 d, between 250 and 364 for the intermediate wait times, and 688 produced when waiting 14 d. Waiting 14 d after treatment before infesting new plants would achieve optimal colony yields but waiting as little as 7 d may still be a reasonable balance between timely production operations and colony yields. Those developing insect mass rearing programmes should consider all variables specific to their procedures that may impact pesticide persistence. [ABSTRACT FROM AUTHOR]

Lithium chloride (LiCl) has a high efficacy against Varroa destructor and a good tolerability for adult bees but the effect of LiCl on the honey bee brood has not been taken into consideration yet. We quantified the mortality of larvae fed with different concentrations of LiCl. For artificially reared larvae already, a concentration of 1 mM had significant toxic effects while under colony conditions, 10 mM was well tolerated. However, a chronic application of the effective concentration of 25 mM elicited brood mortalities between 60 and 90%. Shorter feeding periods of 2 or 4 days reduced the brood damages significantly. Measurements of the lithium concentrations in larvae and pupae during a chronic exposure with 10, 17.5 and 25 mM LiCl revealed respective lithium levels in 5th instar larvae of 7, 13 and 15 mg/kg. No lithium was detectable in 2-day old larvae indicating that pure worker jelly from the hypopharyngeal gland is not contaminated with LiCl. Based on these results, applications of LiCl in colonies with brood should be avoided. [ABSTRACT FROM AUTHOR]

Neoseiulus bicaudus Wainstein (Acari: Phytoseiidae) is a beneficial predatory mite to control spider mites. To evaluate the suitable storage conditions of N. bicaudus, the survival of adult females was observed under different combinations of low temperature (3, 6, 9, or 12°C), food (F) or no food (NF), and high (H) or low (L) humidity conditions for 7, 14, 21, 28, and 35 d. Predator mites' longevity and survival time of 50% and 80% individuals (ST50,80) were measured and compared between treatments. After storage, female and male living mites were paired at 26°C. The progeny parameters were evaluated after storage. Results revealed that survival rate decreased as storage temperature decreased. At 3 and 6°C, fewer mites survived after 28 d. At 9°C, ~50% of the females survived in the FH treatment after 35 d. At 12°C, >80% survived 7–35 d in the FH treatment. Moreover, longevity and ST50,80 were significantly greater in the FH treatment than in the FL or NFH treatments at 3, 9, and 12°C. The highest longevity (48.6 ± 3.7 d) and ST50 (51.6 d) occurred at 12°C in the FH treatment. There was no effect on progeny hatching or survival rates when adults were stored at 9 or 12°C for 28 d. At 9°C, the total preadult development time was 4.20–5.25 d. At 12°C, the total development time was 4.87–4.93 d and there was no significant difference between the storage treatment and control group. These results demonstrated that N. bicaudus females can be successfully stored at 9°C for ~21 d and 12°C for ~28 d with little effect on adult survival or progeny parameters. [ABSTRACT FROM AUTHOR]

The two spotted spider mite, Tetranychus urticae Koch L. (Acari: Tetranychidae), is a plant pest that can lead to severe economic losses in open field cucumber cultivation. Between 2017 and 2019 we studied the abundance of spider mites in the soil to estimate the potential infestation pressure of soil colonizing spider mites. The spider mites were heterogeneously distributed in small concentrations in the soil. Soil colonizing spider mites did not affect spider mite abundance on plants and reversed. We observed that spider mite migration occurred primarily from the edge of the field adjacent to the weed strip. In 2020 and 2021, we investigated the efficacy of the predatory mite Neoseiulus californicus (McGregor) for suppressing spider mite hotspots in the cropland. We compared untreated spider mite hotspots with N. californicus treated hotspots and showed that a single release of predatory mites could result in a high level of control when spider mite infestation density was initially high. With this study, soil can be ruled out as a habitat for spider mites, and attention to spider mite pest control can be directed to plant infestations. The highly sensitive HRM real-time PCR assay was used for the quantification of the spider mites. [ABSTRACT FROM AUTHOR]

In order to investigate the relationship between feather mites and their hosts taking into account host ecology I examined relationships among feather mite load, and sex, age, wing length and body‐condition in the white wagtail Motacilla alba lugens. I captured 288 wagtails in January (the first period) 2002 at a communal roost in Osaka, central Japan. All the wagtails were ringed individually, aged as yearlings (first‐winter) or adults (older) and sexed. I measured wing length, tarsus length and body mass, calculated a body condition index (BCI) and determined the feather mite loads (FML) of each individual by visual examination of the flight feathers of one wing, giving a score using the range 0–5. I recaptured 121 wagtails after an average of 45 days (the second period), and redetermined their FML. FML was not correlated with wing length or body‐condition. Yearlings had higher FML than adults in both periods. Males had greater FML than females in the second period. No significant differences in FML between the first and second periods were detected among yearling females, or adult males, but adult females had significantly lower FML and yearling males had significantly higher FML than the other age–sex classes in the second period. The sexual difference was caused by the lower FML of adult females and the higher FML of yearling males. The BCI of yearling males was the lowest among the four combinations of sex and age‐class. I conclude that wagtails may be able to prevent overpopulation of feather mites on their own plumage. The ability to control mite populations may be related to the condition of the host. [ABSTRACT FROM AUTHOR]

Four predatory mites including Amblyseius swirskii, Cydnoseius negevi, Neoseiulus cucumeris, and Phytoseiulus persimilis, as well as mixture of commercial pesticides named Actara® and Egyxide® (Emulsified vegetable oil) were used to manage the population of Bemisia tabaci, Thrips tabaci, and Tetranychus urticae on red delta star pepper cultivar of Capsicum annuum. All treatments were applied separately and in combination on pepper cultivar grown in a high plastic-net tunnel. The results showed that A. swirskii released separately or combined with other treatments significantly suppressed the population of B. tabaci and T. tabaci to 0.00 and 0.04-2.10 individual/leaf, respectively. Cydnoseius negevi and N. cucumeris significantly reduced B. tabaci population. However, the latter was the most effective against T. tabaci. The numerical densities of movable and egg stages of T. urticae reduced significantly by P. persimilis alone or along with A. swirskii, followed by the release of A. swirskii with N. cucumeris and reached 0.00 individual/leaf. The most effective treatments for T. tabaci with percent reduction ranging from 94.53% to 100% were A. swirskii, N. cucumeris, and all combined treatments. Treatments with pesticides, C. negevi, and A. swirskii + pesticides exhibited less efficiency in controlling B. tabaci, T. tabaci, and T. urticae, respectively. Our findings indicated that the applied bio-agents were efficient, and the inclusion of A. swirskii in programs of integrated pest management is advisable for controlling B. tabaci, T. tabaci, and T. urticae on the pepper cultivar. [ABSTRACT FROM AUTHOR]

Among the Acari, eriophyoid mites are considered important pests as they produce various damage symptoms while feeding on plants. During the general surveys for eriophyoid mites of Mongalbari, Malda, West Bengal, India, one new species, Colomerus terminaliae sp. nov. of the family Eriophyidae was found along the rolling of leaf margin of Terminalia crenulata (Heyne) (Combretaceae). This new phytophagous mite species is described and illustrated from the specimens collected at present study area. The new species is compared with other closely related species and a differential diagnosis is also provided here. The new species belongs to the genus Colomerus Newkirk & Keifer, 1971. This new species is morphologically distinguished from other existing species of Colomerus and it produces leaf rolling at the edges of leaves and causes damage to this economically important tree by its phytophagous mode of nutrition. For proper control of this mite pest, studying its taxonomy and relation to the host plant is essential. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae, is an important pest of horticultural crops worldwide and has developed resistance against multiple kinds of pesticides. To date, information on the resistance to pesticides is inadequate for T. urticae populations in Hainan, south China. In the current study, we determined the resistance to seven pesticides in five field populations of T. urticae that were collected on cucurbit crops in Hainan in 2021. The results showed that T. urticae populations developed high to extremely high resistance to abamectin and bifenthrin and medium to high resistance to pyridaben, profenofos, and cyflumetofen. However, four of the five populations were either susceptible to or had only low resistance to bifenazate and B-azolemiteacrylic. We also determined the frequencies of mutations previously associated with T. urticae resistance to abamectin, pyrethroids, organophosphates, bifenazate, or pyridaben; mutation frequencies as high as 100% were detected for some of the mutations in some of the populations. The results should facilitate the development of rational strategies for the chemical control of T. urticae populations in Hainan, China. [ABSTRACT FROM AUTHOR]

BACKGROUND: Quantifying how chemical tolerance of pest arthropods varies with temperature is important for understanding the outcomes of chemical control, for measuring and monitoring resistance, and for predicting how pesticide resistance will evolve under future climate change. We studied the redlegged earth mite, Halotydeus destructor (Tucker), a winter‐active invasive agricultural pest in Australia. Using a replicated block experiment, we tested the effect of different thermal conditions on the expression of chemical tolerance to a pyrethroid and two organophosphates. Our chemical bioassays were conducted on two redlegged earth mite populations: one possessed organophosphate resistance, whilst the other was susceptible to pesticides. Mites were first acclimated at cool (4 °C) and warm (14 °C) conditions and then exposed to pesticides in both cool (11 °C) and warm (18 °C) test conditions. RESULTS: Warm test conditions generally reduced chemical tolerance to all pesticides relative to cool test conditions. Median lethal dose (LD50) values of mites tested under cool conditions were 1.12–3.57‐fold greater than of mites tested under warm conditions. Acclimation had a variable and small impact on chemical responses. Thermal factors (ratio between test temperatures) were similar between populations for each active ingredient. Despite reduced chemical tolerances under warm test conditions for individual mite populations, resistance factors (ratio between resistant and susceptible mite populations) were relatively consistent. CONCLUSION: Our data provides context for prior theoretical work demonstrating climatically constrained pesticide resistances in Australian redlegged earth mites. Estimates of temperature dependent toxicity measured in this study may be useful in parameterizing models of redlegged earth mite control under an increasingly warm and more variable climate. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this research, the absorption and release rate of the essential oil, Amomum krervanh, by seven different materials were evaluated. Cardboard showed the highest EO absorption capacity (0.93 ± 0.0052 μL of oil/mg of dry cardboard) followed by balsa wood and drawing board with the EO absorption of 0.77 ± 0.043 and 0.62 ± 0.010 μL of oil/mg of dry material, respectively. The results also demonstrated that cardboard had the highest EO retention (52.84 ± 0.687% after 20 min of analysis). Additionally, the essential oil was released from the drawing board and cardboard at the same rate during the observation period. Surface modification of drawing board and cardboard was performed using atmospheric-pressure plasma for enhancing the material properties for Tropilaelaps control. The absorption capacity of cardboard was decreased after plasma treatment at an argon flow rate of 0.25 and 0.5 Lpm for 60 s/cm2. However, the atmospheric-pressure plasma did not change the EO release property of these materials. Scanning electron microscopy analyses indicated a fractured and scaly surface after plasma treatment of gas flow rate at 0.5 Lpm and 1.0 Lpm for 30 s/cm2. The surface chemical composition of materials was not altered following plasma treatment. Although the number of mite-infested brood cells did not differ significantly between treatment groups at the end of the field experiment, Tropilaelaps spp. populations in the plasma-treated cardboard impregnated with EO 5% (v/v) treatment were lower on days 7–14 of the experiment. Thus, parameters related to the atmospheric-pressure plasma should be further optimized to improve the material surfaces for use with essential oils to control honeybee mites. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) has an extensive host range and is the most important pest mite worldwide. Traditional control measures have on the application of the lethal dose of acaricides, thus underestimating the total effects of acaricides on the population dynamics. Our main objective was to evaluate whether it is possible to rely on sublethal concentrations of the pesticide to control mites without getting meaningful crop. To test this hypothesis, we used sublethal concentrations (including LC10, LC20, LC30) of cyflumetofen to see the impact on population parameters of T. urticae. The experiments were performed under laboratory conditions at 25 ± 2°C, 60 ± 5% relative humidity (RH), and a photoperiod of 16:8 (L: D) hours. Results were based on age-stage, two-sex life table analysis. The data showed that sublethal concentrations of the pesticide suppress fecundity, adult longevity (both female and male individuals), and the intrinsic rate of increase significantly. For example, the fecundity in the LC10, LC20, LC30 and control was 36.55, 42.26,and 57.96 eggs/female, respectively, showing significant differences. Similarly, the intrinsic rate of increase (r) are also significantly different between LC30 (r = 0.20) and the control (0.24). The data presented here raise awareness into mite control since using a lower pesticide concentration not only controls the pest population but also produces lower risk to the environment, consumers, and biocontrol agents. Therefore, one could infer that using sublethal concentrations of pesticides would be more beneficial to both the environment and consumers in the long run. [ABSTRACT FROM AUTHOR]

The broad mite, Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) is a highly significant pest in tropical and subtropical regions, with a wide host range that encompasses over 60 plant families. In particular, it can be a major and economically damaging pest on pepper plants, causing significant losses to the crop. The life table parameters of P. latus were determined under laboratory conditions to evaluate the susceptible and resistant cultivars of greenhouse pepper among 14 pepper cultivars, including Selva, Clavesol, Kamus, Chidem, Sympathy, Sven, Kamro, Lumos, Caoba, Bellisa, Sunset, Atlantic D90, Atlantic G50, and Atlantic P5001. The total pre-adult period was significantly different on the pepper cultivars tested, in which the shortest and longest duration was recorded on Atlantic P5001 (5.02 days) and Atlantic G50 (5.94 days), respectively. Adult longevity and total life span had significant differences among pepper cultivars, in which the longest durations were observed on Kamus (21.02 and 26.36 days, respectively). The population growth parameters, including the gross reproductive rate (GRR), net reproductive rate (R 0), intrinsic rate of increase (r), finite rate of increase (λ), and mean generation time (T), as well as the fecundity of the broad mite exhibited significant differences among the cultivars tested. Specifically, the maximum and minimum values of the intrinsic rate of increase (r) were observed in Lomus (0.319 day−1) and Sunset (0.242 day−1), respectively. The gross reproductive rate (28.33 eggs/individual) and net reproductive rate (27.18 eggs/individual) in the Kamus cultivar were significantly higher than those in the other cultivars. Our results indicated that among the pepper cultivars, Sunset, Sympathy, Chidem, and Clavesol were more resistant to P. latus compared with the others. [Display omitted] • Polyphagotarsonemus latus is one of the serious pests of greenhouse pepper. • Antibiosis resistance of 14 cultivars of greenhouse pepper was investigated. • A significant difference was observed in the development and population growth of P. latus on different cultivars. • The highest and lowest population growth of P. latus were obtained on the Lomus and Sunset cultivars, respectively. • Resistant pepper cultivars could be used for the control of the broad mite. [ABSTRACT FROM AUTHOR]

The long-term use of pesticides in the field, and the high fertility and adaptability of phytophagous mites have led to resistance problems; consequently, novel safe and efficient active substances are necessary to broaden the tools of pest mite control. Natural enemies of arthropods typically secrete substances with paralytic or lethal effects on their prey, and those substances are a resource for future biopesticides. In this study, two putative venom peptide genes were identified in a parasitic mite Neoseiulus barkeri transcriptome. Recombinant venom NbSP2 peptide injected into Tetranychus cinnabarinus mites was significantly more lethal than recombinant NBSP1. NbSP2 was also lethal to Spodoptera litura when injected but not when fed to third instar larvae. The interaction proteins of NbSP2 in T. cinnabarinus and S. litura were identified by affinity chromatography. Among these proteins, ATP synthase subunit β (ATP SSβ) was deduced as a potential target. Four binding sites were predicted between NBSP2 and ATP SSβ of T. cinnabarinus and S. litura. In conclusion, we identified a venom peptide with activity against T. cinnabarinus and S. litura. This study provides a novel component for development of a new biological pesticide. [Display omitted] • Novel venom peptides were identified from Neoseiulus barkeri. • Recombinant venom NbSP2 peptide was lethal to Tetranychus cinnabarinus and S. litura through injection. • ATP synthase subunit β (ATP SSβ) was deduced as a potential target. [ABSTRACT FROM AUTHOR]

Stigmaeopsis nanjingensis (Ma and Yuan) (Acari: Tetranychidae) is an important pest of bamboo—feeding behavior and silk production by the female adult mites is seriously harmful to bamboo leaves. Due to its small size, silking and cocooning, its management is difficult. This study discusses a fast and easy method for management of the pest by disturbing the spinning behavior. Stigmaeopsis nanjingensis is host specific and feeds only on bamboo leaves. Leaf margins of bamboo are highly hydrophobic, which makes dsRNA difficult to immerse. Hence, it is a challenge to apply the commonly used feeding method to inhibit gene expression in mites. In this study, we deliver dsRNA to interfere with the expression of fibroin by body wall permeation with a nanocarrier-based delivery system. The dsRNA/nanocarrier formulation droplets could enter the body cavity within 2 min after falling on the mite. The fibroin silencing efficiency was 75.4%, and the results of electron microscopy showed that dsRNA/nanocarrier damage the morphological structure of the silk thread. This study demonstrated the effectiveness of a nanocarrier-based percutaneous dsRNA delivery system in S. nanjingensis and its effect on the fibroin gene that influences the spinning behavior of S. nanjingensis. These findings may provide a new delivery system for RNAi-based control of spider mites that utilize protective webbing in the field. [ABSTRACT FROM AUTHOR]

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The ectoparasite Varroa destructor is the greatest threat to managed honey bee (Apis mellifera) colonies globally. Despite significant efforts, novel treatments to control the mite and its vectored pathogens have shown limited efficacy, as the host remains naïve. A prospective solution lies in the development of Varroa-resistant honey bee stocks, but a paucity of rigorous selection data restricts widespread adoption. Here, we characterise the parasite and viral dynamics of a Varroa-resistant honey bee stock, designated 'Pol-line', using a large-scale longitudinal study. Results demonstrate markedly reduced Varroa levels in this stock, diminished titres of three major viruses (DWV-A, DWV-B, and CBPV), and a two-fold increase in survival. Levels of a fourth virus that is not associated with Varroa—BQCV—do not differ between stocks, supporting a disruption of the transmission pathway. Further, we show that when decoupled from the influence of Varroa levels, viral titres do not constitute strong independent predictors of colony mortality risk. These findings highlight the need for a reassessment of Varroa etiology, and suggest that derived stocks represent a tractable solution to the Varroa pandemic. [ABSTRACT FROM AUTHOR]

Bees are the major pollinators in natural ecosystems and in the agricultural production of several crops used for human consumption. However, they are exposed to multiple stressors that are causing a serious decline in their population. We highlight a major one among them, the Varroa destructor mite (Varroa) that causes severe impacts on the health of honey bee colonies, transmitting a variety of viruses that can affect the survival ability of individual bees and entire colonies. Diagnosis and mite control methods have been intensively studied in recent decades, with many studies in different areas of knowledge having been conducted. This overview summarizes these studies with a focus on colony defense systems, biological characteristics of the parasite Varroa, diagnostic methods used to establish the infestation level of colonies, and currently used control methods. [ABSTRACT FROM AUTHOR]

Date fruit is considered one of the most important fruits crop, that helps in the increment of national income. During storage, date fruits face a lot of problems such as infestation with insects, diseases and mites. The most damaging mite species are Tyrophagus putrescentiae (Schrank) (Astigmata: Acaridae) and Rhizoglyphus robini Claparede (Astigmata: Acaridae). Therefore, this work aims to evaluate two physical control methods, gamma radiation and ozone gas treatment in controlling these two mites. The two mites were irradiated with doses of 0 (control), 100, 200, 300 and 400 Gy in a source of Cobalt-60 type Indian Gamma cell with a dose rate of 0.7967 k Gy /hr. to control eggs and mobile stages. Obtained results concluded that the mites' mortality percentage increases by increasing irradiation doses and the dose for controlling 100% of the two tested mites' species was 400 Gy. While exposing the mites stages to concentrations of 0 (control), 100, 200, 300 and 400ppm of ozone gas, the results showed that the mites mortality percentage increases by increasing ozone concentrations and/or exposure period. The results indicated that ozone has the potential to control the tested mites, particularly at 200 ppm in just 4 hrs.exposure period and 99% at 400 ppm at the same exposure time. The results clearly showed that the mobile stages were more susceptible to radiation and ozone than the egg stage. Also, although radiation and ozone are safe and environmentally friendly methods of pest control, and effective to control the two mites' species with low risk but ozone control was faster and more efficient. [ABSTRACT FROM AUTHOR]

Vineyards are a favorable culture for the habitat of phytophagous mites. These pests feed on the cellular sap of vegetables, causing damage to plants. The aim of this study was to comparatively evaluate the effects of applied biological control of Panonychus ulmi (Koch) (Tetranychidae) using Neoseiulus californicus (McGregor) (Phytoseiidae) on the physicochemical properties and bioactive compounds profile in grapes of Merlot variety, in one single property in the municipality of Bento Gonçalves, Rio Grande do Sul, Brazil. Treatments were conducted in three different areas of the vineyard: area attacked by P. ulmi (AP), area with P. ulmi controlled by N. californicus (APN), and a third area without the presence of mites (AWM). Berries in the AP treatment had lower hardness, with both test probes used (cutting line type and cylinder type). Grapes of AWM treatment had higher red coloration in parameter 'a*', both in the skin and in the pulp. Sugar content did not significantly differ between fruits from grapevines with presence of mites. In grape skins of AP treatment, total phenol, flavonoid, and anthocyanin contents were significantly higher, whereas resveratrol content was lower. Compared to fruits of grapevines without mites (AWM treatment), grapes with biological treatment (APN) had significantly higher contents of sugar, total phenols (pulp and skin), flavonoids (skin), anthocyanins (skin), and antioxidants (skin and pulp). Results suggest that biological control applied using predatory mites increases the concentration of phenolic compounds in fruits, improving the nutritional quality of the grapes. [ABSTRACT FROM AUTHOR]