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Simple Summary: Avocado bronze mite (ABM), Oligonychus punicae Hirst (Acari: Tetranychidae) is one of the most economically important pests in avocado cultivars. Its feeding causes major damage, defoliation and fruit abortion. Control measures of ABM are performed mainly through the use of synthetic acaricides. Alternative control strategies for ABM with a low environmental impact are necessary. The aim of this research was to assess the effect of different concentrations (0.1, 0.5, 1, 5, 10, 15 and 20% (v/v)) of ethanolic extract from Moringa oleifera leaves against adult ABM females. Mites treated with 0.1 and 20% (v/v) of the extract showed mortality of 0.00% and 46.67%, 6.67% and 86.67%, 13.70% and 96.67%, at 24, 48 and 72 h, respectively, compared to the control group. The oviposition and eggs hatch, as well as ABM feeding rates, depended on the extract concentration, which led to a reduction in the growth rate. The M. oleifera leaves ethanolic extract has potential to control O. punicae. Tetranychidae family is a major group of mites causing serious damage in agricultural, vegetable and ornamental crops. Avocado bronze mite (ABM), Oligonychus punicae Hirst (Acari: Tetranychidae) causes major crop damage, defoliation and fruit abortion. At present, the control of this mite depends mainly on agrochemicals. Therefore it is necessary to find alternatives to synthetic pesticides that can help minimize environmental impact and health risks for the consumers. The aim of this research was to assess the effect of different concentrations (0.1, 0.5, 1, 5, 10, 15 and 20% (v/v)) of ethanolic extract of Moringa oleifera leaves against adult ABM females. Mites treated with 0.1 and 20% (v/v) of the extract showed mortality of 0.00% and 46.67%, 6.67% and 86.67%, 13.70% and 96.67%, at 24, 48 and 72 h, as compared to the control treatment, respectively. The number of eggs laid and hatch, as well as ABM feeding rates, depended on the extract concentration, which led to a reduction in the growth rate. M. oleifera leaf ethanolic extract has potential to control O. punicae. [ABSTRACT FROM AUTHOR]

Simple Summary: Phytoseiulus persimilis Athias-Henriot, a mite species widely used in pest management for the control of spider mites, has been commercialized and introduced to numerous countries. In the 1990s, P. persimilis was imported to Taiwan, and a million individuals were released into the field. However, none have been observed since then. In this study, we explored the ecological niche of this species to determine reasons underlying its establishment failure. The results indicate that P. persimilis was released in areas poorly suited to their survival. To the best of our knowledge, the present study is the first to predict the potential distribution of phytoseiids as exotic natural enemies. This process should precede the commercialization of exotic natural enemies and their introduction into any country. Biological control commonly involves the commercialization and introduction of natural enemies. Phytoseiulus persimilis Athias-Henriot, a mite species widely used in the control of spider mites, was imported to Taiwan in the 1990s and was mass-reared and released into the field. However, none have been observed in comprehensive surveys of phytoseiid mites for over 30 years. In this study, the distribution of P. persimilis in Taiwan was predicted, and environmental variables that affect its distribution were analyzed. The mountainous region of southcentral Taiwan was determined to be suitable for the establishment of this species, whereas the four sites at which it was released in the 1990s, particularly those in southwestern Taiwan, exhibited low suitability. Notably, the minimum temperature of the coldest month was identified as a crucial limiting factor affecting the distribution of P. persimilis, indicating that a Mediterranean climate is more suitable for this species. To the best of our knowledge, this study is the first to predict the suitable distribution of exotic predatory mites in a biological control program. The present findings serve as a pivotal assessment framework for the commercialization and foreign introduction of natural enemies. [ABSTRACT FROM AUTHOR]

Bifenazate is a novel acaricide for selective foliar spraying and is widely used to control mites in agricultural production. However, its toxicity to aquatic organisms is unknown. Here, a zebrafish model was used to study bifenazate toxicity to aquatic organisms. Exposure to bifenazate was found to cause severe cardiotoxicity in zebrafish embryos, along with disorders in the gene expression related to heart development. Bifenazate also caused oxidative stress. Cardiotoxicity caused by bifenazate was partially rescued by astaxanthin (an antioxidant), accompanied by cardiac genes and oxidative stress-related indicators becoming normalized. Our results showed that exposure to bifenazate can significantly change the ATPase activity and gene expression levels of the calcium signaling pathway. These led to heart failure, in which the blood accumulated outside the heart without entering it, eventually leading to death. The results indicated that bifenazate exposure caused cardiotoxicity in zebrafish embryos through the induction of oxidative stress and inhibition of the calcium signaling pathway. Image 1 • Bifenazate induces cardiac development toxicity in zebrafish embryos. • Bifenazate causes oxidative stress in zebrafish embryos. • Bifenazate induces cell apoptosis in zebrafish heart. • Bifenazate significantly downregulates ATPase activity, which leads to insufficient blood supply to the heart. [ABSTRACT FROM AUTHOR]

Laboratory and field studies on the use of liquid nitrogen as an acaricide, combined with vacuum cleaning, demonstrated this inert freezing agent to be extremely efficient in reducing the number of live mites in mattresses when compared to vacuum cleaning only. Preliminary observations suggest this treatment does no physical damage to mattresses. Any strategy in the control of house dust mites should incorporate procedures both for the reduction of the mite population and the removal of the allergen pool of faecal pellets and dead mites. [ABSTRACT FROM AUTHOR]

Background Washing of delicate textiles at low temperature combined with mite control is one of the important aims for domestic mite prevention. Objectives Estimation or assessment of mite numbers without and after the application of detergents or detergents with mite control additive. Trials at low temperature, detergents and washing as usual at household conditions (programme of a household washing machine). Methods The domestic mite Dermatophagoides farinae can be cultured on carpet samples under favourable conditions, and the breeding success monitored in terms of population and distribution using the free mite mobility test. The mite containing carpets were cut into pieces in order to investigate the effects of washing at low temperature with different commercial detergents with and without an additive for mite control. The heat escape method was used to assess the number of mites remaining on the carpet pieces. Results The estimation of the mite populations on different carpet pieces before and after washing showed that between 40 and 60% of the mites were able to resist washing, rinsing, spinning and drying. The allergen containing dust, however, was flushed out. In contrast, complete mite control was achieved by the application of the same detergents together with an additive. Conclusion Mite control by low temperature washing is possible with a mite control additive provided that a concentration of benzyl benzoate of about 0.03% is achieved in the washing suds. [ABSTRACT FROM AUTHOR]

Background: Control of dust mites using extremes of temperature is an alternative to the use of acaricides. In the past we have attempted control by freezing with liquid nitrogen. The present paper deals with the opposite extreme, the use of steam. Objective: To assess the feasability and effectiveness of a domestic steam cleaner for the control of dust mites, its effect on mite populations and concentrations of the allergen Der p I. Methods: A domestic stream cleaner was used to treat carpet squares that had been seeded in the laboratory with known numbers of dust mites (Dermatophagoides pteronysinnus). The number of live mites was monitored for a period of 4 months in eight treated carpet squares and eight controls. Dust samples were taken from 12 standardized areas of carpet in a tenement flat in Glasgow, UK, before and after steam cleaning treatment, and the concentration of allergen Der p I was compared with 12 adjacent, control areas. Results: No live mites were found at any time in the treated carpet squares, whereas in the control squares geometric mean mite population density rose from 11 after 3 days to 39 after 1 month, 66 after 2, 122 after 3 and 185 after 4 months. There was a mean reduction of 86.7% in Der p 1 concentration (3.3–.0.44 &mu/g) compared with a reduction of 4.7% (2.22–2.116 μg/g) in control areas, a difference that was statistically significant at the 5% level. Conclusion: These data indicate that steam cleaning has considerable potential as an highly effective and efficient method of killing dust miles and reducing concentrations of Der p 1 in domestic premises. [ABSTRACT FROM AUTHOR]

The acaricidal and fungicidal activities of a new acaricide Allerbiocid, formulated for the control of house dust mites, were investigated. The components of the Allerbiocid formula are: 3% benzyl benzoate (acaricidal and fungicidal), 1% tannic acid (protein denaturant) and 0 5% Tween (surface active agent) in 70% isopropyl alcohol (antiseptic). At application rates of both 150 and 250 ml/m² the acaricidal activity appeared to work by both ingestion and contact and remained active upon contact with mites for up to 10 weeks. When Sabouraud agar was treated with Allerbiocid at a concentration of 5 ml/20 ml medium, the preparation was also found to have fungicidal and fungistatic activities on various species of fungi commonly found in house dust. Allerbiocid contains tannic acid which is a protein denaturant. Levels of Der p I in dust were found to be reduced by over 90% after treatment with Allerbiocid. The importance of denaturation of mite faecal allergens and allergens associated with dead fungal spores is discussed. [ABSTRACT FROM AUTHOR]

We report on the mechanisms, the environmental changes and patient compliance with regard to conventional and new dust and mite avoidance measures to prevent allergic symptoms caused by mite allergens, taking into account both allergen contamination and the developmental success of pyroglyphid Acari. Twenty patients with persisting rhinitic complaints were selected and matched. Although the patients had performed some conventional dust and mite avoidance measures (patient compliance was 90%). the dwellings proved to be a stimulus for mite development. Moisture problems due to faulty construction and excessive moisture production were common. Since humidity conditions could not be changed at short notice, the 20 homes were subjected to the new variants of mite allergen avoidance based on intensive cleaning without (control) and with an acaricide incorporated (acaricidal cleaner [Acarosan]). After the carrying out of conventional avoidance measures, these patients still had allergic symptoms, and dust from only 23 to 52% of their textile objects was under the proposed guanine (mite faeces indicator) risk level. Only the acaricidal cleaner was able to decrease the allergenic mite load (and the burden of the patients) significantly in this 12 month period. With respect to mite-extermination, acaricidal cleaning was 88% better than intensive cleaning. Reduction of guanine was .18% better in the Acarosan treatment group. Clinical results have been reported elsewhere, A significant difference in favour of the acaricidal cleaning was seen in both subjective (as regards symptoms) and in objective data (total IgE). Another 50 patients were questioned. About 90% were willing to spend two weekends (70%). or at the most one weekend (20%) per year sanitizing the dwelling by cleaning it with the whole family. The authors of this report consider acaricidal cleaning to he a significant improvement in the management of mite-allergic diseases, such as rhinitis. Compared with the replacement of home textiles, this treatment is less expensive and more effective, Patient compliance is acceptable, but depends on acceptance by physicians and the initial motivation and consequent burden on the patient. [ABSTRACT FROM AUTHOR]

Resurgence of pest insects and mites and secondary pest outbreaks are commonly observed following pesticide applications on agricultural commodities. Reduction of natural enemy populations is the major factor blamed for these phenomena but insect or mite hormesis is a second, often overlooked factor which may be partially responsible. A major impact of hormesis is that it often leads to the need for additional pesticide treatments and can result in a spiralling increase in the use of pesticides, a term labelled in entomological literature as the ‘pesticide syndrome’. [ABSTRACT FROM AUTHOR]

Twenty-three pesticides were evaluated in 18 trials in 1974-79 for the control of red spider mite (Tetranychus urticae) on strawberries in areas in England where strains of mites resistant to the organophosphorus pesticides and dicofol were known to occur. The organophosphorus pesticides chlorpyrifos and triazophos continued to give good control at most of the sites. Demeton-S-methyl, dioxathion and omethoate used at only two of the sites significantly reduced the number of mites. Pirimiphos-methyl, dimethoate and quinalphos used at only a few sites did not give a significant control. The carbamates aldicarb, thiofanox, formetanate and methiocarb usually gave significant control. Of all the pesticides tested, cyhexatin consistently gave the best control The specific acaricides amitraz, dienochlor, dinobuton, fenbutatin oxide, propargite and quinomethionate were usually effective. Dicofol gave much more variable results than in earlier trials, probably because of resistance. [ABSTRACT FROM AUTHOR]

During 1978 and 1979, the control of red spider mite on strawberries by the predacious mite Phytoseiulus persimilis was studied at two sites in Hampshire where crops were grown in ‘walk-in’ plastic tunnels. An introduction of at least two predators per plant in March was required to control red spider mite in one experiment. In the second experiment, introductions of small numbers of predators (fewer than two per plant) in August controlled mites on newly planted runners before diapause. Similar numbers of predators introduced in the following March, 10 days after red spider mite eggs were seen, controlled mite infestations throughout the growing season. Controlling mites in the autumn before diapause was considered important. [ABSTRACT FROM AUTHOR]

Narcissus bulbs were fumigated with methyl bromide at 18°C using dosages of 130, 172, 200, 212-5, 250, 260 or 340 mg hr/1. during three storage seasons. Samples were checked for pests, especially bulb scale mite (Steneotarsonemus laticeps (Halb.)), while others were grown on and checked for effects on subsequent growth. Laboratory examination of samples after fumigation showed that all the mites had been killed by the five largest but not by the two smallest dosages. However, live mites were found when bulbs fumigated with any of the dosages were lifted after another growing season. Mite populations also increased while bulbs were in store. No significant phytotoxicity was observed after any except the largest of the dosages tested. A treatment of 250 mg hr/1, with five hours' exposure is recommended as being virtually nonphytotoxic and providing satisfactory control of bulb scale mite. [ABSTRACT FROM AUTHOR]

In small-scale trials narcissus bulbs, cultivar Standard Value, heavily infested with bulb scale mite (Steneotarsonemus laticeps (Halb.)) were treated with methyl bromide over a range of concentration × time products from 102 to 251 mg.hr/1. at temperatures between 19 and 24°C. All treatments killed both the mites and their eggs without damaging the bulbs. Fumigated bulbs flowered normally without stunting or distortion. [ABSTRACT FROM AUTHOR]

Addresses the sustainability of mite vaccinations for the management of spider mites in vineyards. Definition of a sustainable technique; Effects of agronomic practices on the vaccinations; Reduction of the population of Pacific mites.

A series of 1,2,4,5-tetrazines has been synthesised and screened for acaricidal activity. Laboratory tests have shown several of the compounds to be highly active mite ovicides. Further examination in the field has identified a highly active compound, which gives prolonged control of mites on top fruit. The selected compound (clofentezine) is shown to be safe to mite predators and beneficial species and has been developed commercially for use on top fruit. (Clofentezine is the B.S.I. approved common name of 3,6- bis-(2-chlorophenyl)-1,2,4,5-tetrazine). [ABSTRACT FROM AUTHOR]

A new class of compounds derived from hydroquinone ethers showed high and predominantly ovicidal activity against the two-spotted spider mite, Tetranychus urticae Koch. The sequence of compounds synthesised and the factors which appeared to have contributed most to the discovery of these promising acaricides are presented. [ABSTRACT FROM AUTHOR]

Studies the effects of varying acaricide concentrations and acaricidal combinations on the rate of spin down and thread length, effect of mites after spinning down and implications of spin down in the context of mite control and the relationship between webbing and efficacy of ovicides. Impact of higher concentrations of cyhexatin on spin down rate; Effect of amitraz on webbing production.

Reports on a study conducted to determine which direct and indirect species interactions were most important in determining the within-season dynamics of apple rust mite (Acuus schlechtendali) (Eriophyidae) in a series of Nova Scotia. Role of Typhlodromus pyri and Zetzellia mali in direct reduction of the rust mite population growth rate.

Discusses the susceptibility aspect of seven strains of Cheyletus eruditus (C. eruditus) to organophosphate acaricides. Comparison of C. eruditus strains originating from field populations with that from laboratory strains; Use of C. eruditus population in the management of acaroid mites.

The study was undertaken to evaluate the effect washing at various temperatures would have on the house dust mite, Dermatophagoides pteronyssinus, and its allergens. Young and old mite cultures underwent a simulated washing programme. To record the number of live mites prior to and after washing a new counting method was applied. lime findings demonstrated that although washing reduced the number of live mites, a washing programme at minimum temperature 58°C was required in order to achieve complete extermination of the house dust miles, A distinct protein loss was observed when washing at higher temperature, thus further reducing the total allergen pool without loss of allergen activity as determined by direct RAST. [ABSTRACT FROM AUTHOR]

Qualitative and semi-quantitative microscopic analyses were performed on the mite populations in dust samples collected from the byres and hay and grain storages of 11 farms in Eastern Finland. Storage mites were found in all farms. The mite fauna was more abundant in the byres and hay storages than in the grain storages. The most common species or genera were Acarus siro, Acarus farris, Glycyphagus domesticus, Lepidoglyphus destructor, Cheyletus eruditus, Tydeus spp., and Tarsonemus spp. The results imply that also in northern climates storage mites should be considered as possible causes of allergic disorders among farming populations. [ABSTRACT FROM AUTHOR]

This article cites a series of experiments on the use of acaricides in controlling tetranychus urticae in commercial cucumber glasshouses in the Lea Valley, England. The treatments were applied to plots of five or six plants and were replicated in most of the trials. The findings showed that tetradifon gave consistently good results. Two new pesticides, binapacryl and thioquinox gave good results but were phytotoxic. Dicofol also gave variable results and there was evidence of resistance to the material in one of the trials. Throughout the trials the phytotoxic effects of several of the agents being tested has been one of the most important limiting factors in their application on cucumbers.

This article discusses several insecticides used to control cyclamen mite on cyclamen and strawberries. The cyclamen mite is known to be a serious pest of many ornamental plants including cyclamen, saint paulia, gerbera, ivy and begonia. It is also troublesome in some years on field strawberries. In this study, sprays of fluoroacetamide, endrin and Thiodan gave good control of cyclamen mite in trials on cyclamen and strawberry in 1960. In one trial, Kelthane at 0.04 per cent gave promising results on strawberries. Repeated applications of 0.025 per cent Kelthane on cyclamen under glass also gave good results. Eradex has showed promising results in one trial on strawberries.

The article offers information on the 15th International Congress of Acarology and McMurtry Award in Antalya, Turkey from September 2-8, 2018. Topics include medical importance of parasitic and free-living mites; mite-plant interactions; soil acarology; and biological control of mites. It featured several people related to entomology including Sebahat K. Ozman-Sullivan, Ferit Turanli and Peter Schausberger.

Selenium is a trace element necessary for living organisms. It exists mainly in the form of selenite in nature. In plants, selenium can enhance defenses against pests. In this study, transcriptome sequencing technology was used to analyze the response mechanism of Tetranychus cinnabarinus to plant-mediated selenium treatment. We tested four sodium selenite treatments (5, 20, 50, and 200 μM) that were the same for short (2 d) and long (30 d) treatment durations. The results showed that the number of differentially expressed genes (DEGs) in the short-term treatment was greater than in the long-term treatment. This indicated that the gene expression of spider mites gradually stabilized during the selenium treatment. Regardless of the long-term and short-term conditions, spider mites had the largest response to the 20 μM sodium selenite treatment. The functional annotation classification of DEGs showed no significant difference under different concentrations and treatment durations. A total of 25 genes were differentially expressed in all eight treatments, including four down-regulated cytochrome P450 genes and one up-regulated chitinase gene. We speculate that selenium may have the potential to enhance the activity of chemical acaricides. Transcriptome sequencing of sodium selenite treatment at different concentrations and different times revealed the response mechanism of spider mites under plant-mediated selenium treatment. At the same time, it also provides new clues for the development of methods for preventing and controlling spider mites with selenium. • Transcriptome sequencing of spider mites treated with plant-mediated sodium selenite. • Mites had the largest response at the 20 μM sodium selenite treatments. • There was little difference between the long-term and short-term treatment. • DEG analysis of the eight treatments provides clues for future mite control. [ABSTRACT FROM AUTHOR]

• Fungus-resistant grape varieties allow drastically fewer fungicide applications. • Fungicide reductions are stronger in organic than in conventional vineyards. • Fungicides harm non-target predatory mites but not pest mites. • Fungus-resistant varieties facilitate natural pest control. Pesticides can have detrimental effects on non-target biodiversity, especially in intensively managed agroecosystems such as vineyards. However, new fungus-resistant grape varieties can greatly reduce the need and use of fungicides. Fungicides can have direct and indirect effects on economically important predatory mites (mainly Phytoseiidae) and on phytophagous mites (Tetranychidae, Eriophyidae) on which they prey. We investigated the impact of fungicide treatments on beneficial and phytophagous mite densities in 32 vineyards of organic and conventional wineries planted with susceptible and fungus-resistant grape varieties in the Palatinate region, Germany. Organic vineyards were sprayed with different formulations of sulfur, copper and potassium bicarbonate, while conventional vineyards received mostly synthetic fungicides. Fungicide applications were reduced by 47-80 % in fungus-resistant varieties, with stronger reductions under organic than under conventional management. Regardless of organic or conventional management, predatory mites (Phytoseiidae and Tydeidae) were significantly enhanced in vineyards planted with fungus-resistant varieties. Contrastingly, phytophagous mites (Eriophyidae) were enhanced in vineyards with fungus-susceptible varieties and in those under organic management. Densities of further predatory mite families increased under organic farming (Anystidae) or showed an interactive response to farming system and grape variety (Trombidiidae). Reduced fungicide applications through cultivation of fungus-resistant varieties enhance predatory mite densities and thus contribute to higher natural pest control potential. Thus, the cultivation of fungus-resistant grape varieties is an effective approach towards more environmentally friendly viticulture. [ABSTRACT FROM AUTHOR]

Simple Summary: Varroa destructor, a parasitic mite of Apis mellifera, is causing severe damages to honey bee colonies worldwide. There are very few acaricides available to manage the parasite, and so the evolution of the mite's resistance to acaricides poses a serious threat to controlling the mite. Using a combined approach that includes bioassays and genotyping, we estimated the expected efficacy of the treatments with acaricide products based on coumaphos, amitraz, and pyrethroids in apiaries from one of the most important beekeeping regions in Spain. This information was shared with the beekeeping community so that they can take informed and scientific-based decisions in the most convenient way to manage the parasite. Varroa destructor is an ectoparasitic mite causing devastating damages to honey bee colonies around the world. Its impact is considered a major factor contributing to the significant seasonal losses of colonies recorded every year. Beekeepers usually rely on a reduced set of acaricides to manage the parasite, usually the pyrethroids tau-fluvalinate or flumethrin, the organophosphate coumaphos, and the formamidine amitraz. However, the evolution of resistance in the mite populations is leading to an unsustainable scenario with almost no alternatives to reach an adequate control of the mite. Here, we present the results from the first large-scale and extensive monitoring of the susceptibility to acaricides in the Comunitat Valenciana, one of the most prominent apicultural regions in Spain. Our ultimate goal is to provide beekeepers with timely information to help them decide what would be the best alternative for a long-term control of the mites in their apiaries. Our data show that there is a significant variation in the expected efficacy of coumaphos and pyrethroids across the region, indicating the presence of a different ratio of resistant individuals to these acaricides in each population. On the other hand, the expected efficacy of amitraz was more consistent, though slightly below the expected efficacy according to the label. [ABSTRACT FROM AUTHOR]

There is increasing interest in the possibility of using eriophyid mites as biological control agents of invasive alien weeds; however their small size and our lack of knowledge about their general biology present challenges to evaluating their risk to nontarget plants. Aceria salsolae has been proposed as a candidate agent for Russian thistle (Salsola tragus) in the USA. During host specificity testing this mite could sometimes persist on five nontarget species under laboratory no-choice conditions. We conducted a series of no-choice laboratory experiments and a field experiment to try to delineate the physiological and ecological host ranges of this mite and assess its risk to nontarget plants. In the laboratory, A. salsolae increased exponentially on S. tragus , multiplying about 80 fold in 5 weeks. Low levels of reproduction were observed on some plants of Atriplex coronata , Bassia hyssopifolia , B. prostrata , Kochia scoparia and Suaeda calceoliformis in the laboratory during 5 weeks, but mean mite densities remained low (less than 6 fold increase vs. 80 fold on S. tragus). In a field experiment in which plants were inoculated with mites in June and then harvested when they began to produce seed, mites persisted on A. coronata for up to 9 weeks after inoculation, but at extremely low densities, and with no evidence of reproduction. No mites persisted on A. truncata , B. hyssopifolia, or S. calceoliformis. Mite densities were lower on all plants in the field than in the laboratory, probably due to increased mortality and the opportunity to disperse by wind. No signs of damage were observed on any of the nontarget plants in the laboratory or the field experiments. We conclude that this mite is not likely to multiply on any of these plants under field conditions, and that it is not expected to pose a risk to any nontarget plants in the contiguous USA. [ABSTRACT FROM AUTHOR]

Natural pesticides are potential alternatives to conventional chemical pesticides. Recently, studies on pesticide–pest interactions have combined empirical biochemical measurements and practical field experiments. In this study, we performed laboratory and field efficacy analysis and biochemical characterization of two phytochemicals (2,4-di-tertbutylphenol (DTBP) and ethyl oleate (EO)) for carmine spider mite Tetranychus cinnabarinus control. DTBP and EO controlled mites by inhibiting egg hatchability and showed significant residual toxicity in laboratory tests. The control efficacy was confirmed in eggplant and cucumber field trials in three provinces in China. Oxidative stress induced by antioxidant enzymes (superoxide dismutase and peroxidase) and detoxification metabolism (involving carboxylesterase and/or mixed-function oxidase) may be involved in the response of mites to DTBP and EO. This study demonstrates the potential of DTBP and EO as effective acaricides for the control of spider mites and provides researchers a better understanding of acaricide–mite interactions. • DTBP and EO effectively controlled T. cinnabarinus under laboratory and field conditions. • Oxidative damage is the most likely causative mechanism in T. cinnabarinus response to the toxicity of DTBP and EO. • The ovicidal activities of DTBP and EO were strongly affected by egg age. • These findings provide a crucial theoretical basis for future commercialization of DTBP and EO as natural acaricides. [ABSTRACT FROM AUTHOR]

Simple Summary: The almond industry in California produces approximately 80% of the world's supply and currently consists of roughly 0.45 million bearing and non-bearing hectares. Spider mite management is a component of annual arthropod management strategies on almond. Regularly, acaricides containing the active ingredient, abamectin, are applied in spring when mites are not yet present or well below a level which justifies treatment, in other words applied to prevent rather than treat existing populations. Although other acaricides are used, those containing the active ingredient, abamectin, accounted for 68% to 95% of spring (preventative) applications between 2005 and 2017. Although the strategy is widely employed in the almond industry, there are no published studies supporting the practice. Moreover, the strategy runs contrary to sustainable, integrated pest management practices by forgoing monitoring, reliance on spider mite natural enemies, and economic threshold levels. In this study, we conducted large field trials to evaluate the effectiveness of preventative acaricide applications. Results showed that farmers can forego a preventative strategy since spider mite densities typically remain well below damaging levels through the period critical for tree growth and nut yield. Also, results showed that such a heavy reliance on abamectin has led to a low to moderate level of resistance developing in some spider mite populations in the southern and mid San Joaquin Valley. Field experiments were conducted in two commercial almond orchards located in the southern San Joaquin Valley during 2016 and 2017 to evaluate a "preventative" strategy to manage spider mites. Pacific mite, Tetranychus pacificus McGregor, was identified as the only mite species infesting the experimental sites in both years. We monitored mites weekly in 3.6-hectare plots over approximately 21 weeks in 2016 and in 2017 using guidelines developed by the University of California. In late May, prior to the detection of mites, preventative acaricide treatments, abamectin, cyflumetofen, or etoxazole were applied to the experimental plots at a field rate. In 2016 and 2017, mite densities in all the treatments increased at early-July, peaked at mid-August, and were undetectable by late August. Preventative acaricide-treated plots in 2016 tended to have significantly lower mite densities than in the untreated control plots. Although in 2017, densities in the acaricide-treated plots tended to not significantly differ from control plots. Mite feeding injury, measured as mean cumulative mite-days, did not exceed the economic threshold during the experiment. The biological control agent, sixspotted thrips, Scolothrips sexmaculatus (Pergande) likely played a role in controlling mite populations at mid and late August. Our results indicate that a preventative strategy does not play a definitive role in T. pacificus management on almond. Additionally, acaricides with the active ingredient, abamectin, are heavily relied on as preventative treatments. We assessed populations of T. pacificus from the mid and southern San Joaquin Valley and found increased tolerance to a medium level of resistance to the acaricide. [ABSTRACT FROM AUTHOR]

• Natural enemies can regulate populations of Brevipalpus yothersi. • Phytoseiid and cheyletid predators were evaluated for control of Brevipalpus yothersi. • Amblyseius largoensis suppressed Brevipalpus yothersi on citrus plants. • Predatory mites can be important in IPM programs tailored to manage citrus leprosis. Citrus leprosis is a serious viral disease of citrus transmitted by Brevipalpus mites. The disease is present in South America, Central America, and Mexico, but not in the United States. One of its primary vectors, however, is present in Florida and other southern states. Non-viruliferous Brevipalpus yothersi (Acari: Tenuipalpidae) are present in Florida and could facilitate the spread of the disease if citrus leprosis viruses (CiLVs) are introduced into the state. In preparation for the possible incursion of CiLVs, we evaluated the biological control potential of four predatory mite species (Neoseiulus longispinosus , N. californicus , Amblyseius largoensis ; Acari: Phytoseiidae) and Hemicheyletia bakeri (Acari: Cheyletidae) that are naturally associated with Brevipalpus spp. in citrus. In laboratory no-choice assays, the phytoseiid mites preyed mostly upon immature stages of B. yothersi , while H. bakeri preyed mainly on adults. In dual choice assays, all predators preferred Tetranychus urticae (Acari: Tetranychidae) over B. yothersi , but A. largoensis consumed more B. yothersi than the other three predators. A greenhouse experiment was performed to evaluate the potential of A. largoensis and H. bakeri to suppress B. yothersi populations on citrus trees. Four predator release treatments consisting of single or combined releases of A. largoensis and H. bakeri at a 1:10 (predator: B. yothersi) ratio were tested. Releases of A. largoensis alone or in combination with H. bakeri effectively suppressed B. yothersi and reduced damage to citrus plants. Release of H. bakeri alone, however, had no suppressive effect on B. yothersi populations. Overall, our results show that A. largoensis could be an efficient biological control agent of B. yothersi and could play an important role in citrus IPM programs tailored to manage citrus leprosis. [ABSTRACT FROM AUTHOR]

Background: Selenium has shown effectiveness in protecting plants from herbivores. However, some insects have evolved adaptability to selenium., Results: Selenium accumulation in host plants protected them against spider mite feeding. Selenium showed toxic effects on spider mites by reducing growth and interfering with reproduction. After 40 generations on selenium-rich plants, a Tetranychus cinnabarinus strain (Tc-Se) developed adaptability to selenium, with an increased rate of population growth and enhanced ability for selenium metabolism. The high expression of two genes (GSTd07 and SPS1) in the selenium metabolism pathway might be involved in selenium metabolism in spider mites. After GSTd07 and SPS1 were silenced, the selenium adaptability decreased. Recombinant GSTd07 protein promoted the reaction between sodium selenite and glutathione (GSH) and increased the production of sodium selenite metabolites. The results indicated that GSTd07 was involved in the first step of selenium metabolism., Conclusion: Plants can resist spider mite feeding by accumulating selenium. Spider mites subjected to long-term selenium exposure can adapt to selenium by increasing the expression of key genes involved in selenium metabolism. These results elucidate the mechanism of the interaction between mites and host plants mediated by selenium. This study of the interaction between selenium-mediated host plants and spider mites may lead to the development of new and less toxic methods for the prevention and control of spider mites. © 2021 Society of Chemical Industry., (© 2021 Society of Chemical Industry.)