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The Varroa mite, Varroa destructor , poses one of the most serious threats to honey bees worldwide. Although coumaphos, an anticholinesterase pesticide, is widely used for varroa mite control, little information is available on the properties of Varroa mite acetylcholinesterases (VdAChEs). In this study, three putative VdAChEs were annotated and named VdAChE1, VdAChE2, and VdAChE3. All VdAChEs possessed most of the functionally important signature domains, suggesting that they are catalytically active. Phylogenetic analysis revealed that VdAChE1 was clustered into a clade containing most arthropod AChE1s, whereas VdAChE2 and VdAChE3 formed a unique clade with other arachnid AChEs. VdAChE1 was determined to be membrane-anchored, but both VdAChE2 and VdAChE3 are soluble, as judged by electrophoresis in conjunction with western blotting. Tissue-specific transcription profiling revealed that VdAChE1 was most predominantly expressed in the synganglion. In contrast, VdAChE2 was most predominantly expressed in the legs and cuticle. VdAChE3 showed negligible expression levels in all the tissues examined. In a kinetic analysis using recombinant VdAChEs, VdAChE1 exhibited the highest catalytic efficiency, followed by VdAChE2 and VdAChE3. Inhibition experiments revealed that VdAChE1 was most sensitive to all tested inhibitors. Taken together, VdAChE1 appears to be the major synaptic enzyme with a more toxicological relevance, whereas VdAChE2 is involved in other noncatalytic functions, including chemical defense against xenobiotics. Current findings contribute to a more detailed understanding of the evolutionary and functional traits of VdAChEs and to the design of novel anticholinesterase varroacides. [Display omitted] • Three acetylcholinesterases (VdAChE1, VdAChE2, and VdAChE3) were identified in varroa mites • VdAChE1 exhibited the highest catalytic efficiency and was most sensitive to all tested inhibitors. • VdAChE1 exists in membrane-anchored form, whereas both VdAChE2 and VdAChE3 exist in soluble form. • VdAChE1 appeared to be the major synaptic enzyme with a more toxicological relevancy. • VdAChE2 might be involved in chemical defense against xenobiotics. [ABSTRACT FROM AUTHOR]

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

The intense spraying of insecticides has negatively affected the management of the leprosis vector mite, Brevipalpus yothersi , requiring additional acaricide applications. Therefore, the main objective of this study was to assess the toxicity of the acaricide spirodiclofen and several insecticides, alone or combined, on different developmental stages of B. yothersi in the laboratory and field. Additionally, the concentration of the active ingredient spirodiclofen was quantified in the spray solutions. The efficacy of spirodiclofen on the eggs and adults of B. yothersi was drastically reduced when spirodiclofen was sprayed in a mixture with cypermethrin, phosmet, or imidacloprid, with 65.4%, 57.2%, and 53.4% of reduction in eggs mortality, and 24.4%, 57.7%, and 17.6% of reduction in adult mortality, respectively. In the field, the addition of insecticides to the spirodiclofen solution decreased the period for reinfestation of the mites by the acaricide from 127 days with spirodiclofen alone to 42 (cypermethrin), 43 (phosmet), and 52 (imidacloprid) days. There was no significant reduction in the spirodiclofen concentration when mixed with insecticides. Our results indicate that the insecticides cypermethrin, phosmet, and imidacloprid antagonize the efficacy of spirodiclofen on eggs and adults of B. yothersi. [Display omitted] • Cypermethrin, phosmet, and imidacloprid antagonize spirodiclofen efficiency on eggs and adults of Brevipalpus yothersi. • These insecticides increase the time to reduce Brevipalpus yothersi population by spirodiclofen when in a mixture. • The control period of the mites is reduced. • Spirodiclofen content is similar to an acaricide solution with or without insecticides. [ABSTRACT FROM AUTHOR]

Mite infestations in laying hens can cause losses to producers due to stress, reduced egg production and even death of birds. A new species of mite, Allopsoroptoides galli ( A. galli ), Analgoidea: Psoroptoididae, was recently identified in commercial laying farms in Brazil, causing damage due to its highly aggressive infestation that results in a sharp drop in egg production and culling. The present study evaluated the acaricidal action of a formulation containing fluralaner (Exzolt) against A. galli. Thirty-four laying hens naturally infested with A. galli were equally divided into a fluralaner-treated group and an untreated control group. The fluralaner-treated group received Exzolt in drinking water at a dose of 0.05 mL/kg body weight (equivalent to 0.5 mg fluralaner/kg body weight), twice, 7 d apart. Both groups were followed for 70 d evaluating the level of infestation by counting mites in skin scrapings and assessment of skin lesions. The average mite count of the treated group decreased significantly, dropping from 61.6 to 3.8 mites (D+7 to D+70). The efficacy progressively increased on subsequent days, reaching 98.8% on d +56 post-treatment and 96.9% on d +70. Recovery of skin lesions was observed after administration of Exzolt, showing a marked remission in the degree of lesions (2.5 on d −14 to 0.2 on d +70). The mean number of mites in the untreated control group ranged from 79.3 to 124.1 and the lesion score from 2.6 to 2.9, thus remaining stable throughout the study. The results obtained in the present study demonstrated that Exzolt administered at a dose of 0.05 mL of product/kg body weight (equivalent to 0.5 mg of fluralaner/kg body weight), twice at a 7-d interval, in drinking water was effective in the treatment of the mite Allopsoroptoides galli in naturally infested laying hens. [ABSTRACT FROM AUTHOR]

The present study compared the efficacy of Apivar (a.i. amitraz) and Apiguard (a.i. thymol) in controlling the mite Varroa destructor during spring 2010 and autumn 2011, in the Balearic Islands (Spain). Number of fallen mites (NFM) was counted weekly and the efficacy of treatments was evaluated by using the percentage of reduction of the average daily fallen mites (%R). During spring assay, the average NFM was highly reduced in Apiguard (89.8%) compared to Apivar (64.3%) group, with significant differences between Apiguard and control group (untreated group) in post-treatment week. In autumn assay, Apivar and Apiguard colonies had an average reduction of the NFM of 17.9% and 30.8% respectively, showing a tendency in reduction between control and Apiguard group in post-treatment week. In both assays, %R was higher in Apiguard than in Apivar, but no significant differences were found between treatments in any of the seasons. Apiguard was less efficacious during November-December, probably due to the low external temperatures that hampered an optimal volatilization of the product. The lower efficacy of Apivar is probably related to the resistance of V. destructor to this chemical miticide, which has been used during the last 30 years. Results of this study showed that in Mediterranean conditions, spring is an appropriate period for applying Apiguard to the colonies, whereas application in late autumn would decrease the efficacy of the product. Apiguard may represent an alternative product for integrated control due to the low risk of mite resistance and residues in bee products.

Background: Milbemycins, a group of 16-membered macrolides with potent anthelminthic and insecticidal activity, are produced by several Streptomyces and used widely in agricultural, medical and veterinary fields. Milbemycin A3 and A4, the main components produced by Streptomyces bingchenggensis, have been developed as an acaricide to control mites. The subsequent structural modification of milbemycin A3/A4 led to other commercial products, such as milbemycin oxime, lepimectin and latidectin. Despite its importance, little is known about the regulation of milbemycin biosynthesis, which has hampered efforts to enhance milbemycin production via engineering regulatory genes. Results: milR, a regulatory gene in the milbemycin (mil) biosynthetic gene cluster of S. bingchenggensis, encodes a large ATP-binding regulator of the LuxR family (LAL family), which contains an ATPase domain at its N-terminus and a LuxR-like DNA-binding domain at the C-terminus. Gene disruption and genetic complementation revealed that milR plays an important role in the biosynthesis of milbemycin. β-glucuronidase assays and transcriptional analysis showed that MilR activates the expression of the milA4-E operon and milF directly, and activates the other mil genes indirectly. Site-directed mutagenesis confirmed that the ATPase domain is indispensable for MilR’s function, and particularly mutation of the conserved amino acids K37A, D122A and D123A, led to the loss of MilR function for milbemycin biosynthesis. Overexpression of an extra copy of milR under the control of its native promoter significantly increased production of milbemycin A3/A4 in a high-producing industrial strain S. bingchenggensis BC04. Conclusions: A LAL regulator, MilR, was characterized in the mil gene cluster of S. bingchenggensis BC04. MilR could activate milbemycin biosynthesis through direct interaction with the promoter of the milA4-E operon and that of milF. Overexpression of milR increased milbemycin A3/A4 production by 38 % compared with the parental strain BC04, suggesting that genetic manipulation of this activator gene could enhance the yield of antibiotics. [ABSTRACT FROM AUTHOR]

Resistance to conventional synthetic pesticides has been widely reported in Dermanyssus gallinae in different aviary systems. Cardboard traps containing acaricides had been introduced as a successive device for collection and control of the poultry red mite. The present study assessed field efficacy of traps containing carvacrol in the control and reduction of D. gallinae in laying poultry farm. Two different carvacrol-based formulations were tested for their toxicity and possible repellent activity on D. gallinae to determine the most appropriate formulation and concentration to be used in the field study. In vitro tests confirmed that 1 % carvacrol formulation with ethoxylated castor oil as emulsifier was significantly toxic to D. gallinae without any dissuading effect in comparison to ethanol and higher concentrations of carvacrol ( p < 0.05). A subsequent in vivo experiment in a cage system laying farm demonstrated significant acaricidal activity for traps containing 1 % carvacrol. Throughout the study, untreated cardboard traps were used for monitoring mite populations. Carvacrol-impregnated traps were efficacious in the control of D. gallinae and led to over 92 % reduction in mite's population after 2 week of application. Toxic effects of carvacrol maintained through 2 weeks after the last application of traps. Results of the present study suggested that effective control of the poultry red mite can be achieved by traps containing carvacrol. These traps can be used safely in poultry facilities without any concern about residues in eggs, meat, and environment. [ABSTRACT FROM AUTHOR]

Oxalic acid is one of the organic acids used for controlling Varroa destructor, a mite parasitizing the honey bee (Apis mellifera). The aim of this work was to examine the effect of oxalic acid applied by sublimation on honey bee colony fitness, and to compare it with the effect of amitraz, a routinely used synthetic acaricide. Bee colonies of equal strength were randomly divided into two groups. In December 2014, one group was treated with amitraz in the form of aerosol, and the second group was treated with oxalic acid applied by sublimation. The colonies were monitored over winter. Dead bees found at the bottom of the hive were counted regularly and examined microscopically for infection with Nosema sp. (Microsporidia). At the end of March 2015, living foragers from each hive were sampled and individually examined for Nosema sp. infection. Colony strength was evaluated at the beginning of April. No adverse effect of oxalic acid on colony strength was observed despite the fact that the total number of dead bees was non-significantly higher in the oxalic acid-treated group. Examination of dead bees for Nosema infection did not reveal significant differences in spore numbers between the experimental groups. There was a substantial difference in living individuals, however, with a significantly higher amount of spores per bee found in the amitraz-treated colonies compared to the oxalic acid-treated colonies. Compared to amitraz, oxalic acid applied by sublimation showed no adverse effects on bee colony fitness or on successful overwintering. [ABSTRACT FROM AUTHOR]

The article offers the author's insights on her experience of observing her African violet (AV) plants infected with Impatients Necrotic Spot Virus (INSV) and how she deals with them. Topics include the important things to know on INSV, the precautions to reduce the risk of encountering mites, thrips, and INSV on plants, and the use of test kits to detect INSV.

The twospotted spider mite, Tetranychus urticae Koch (Trombidiformes: Tetranychidae), is considered one of the most important phytophagous mites causing considerable damage in several agricultural crops. The aim of this study was to evaluate the susceptibility to gamma irradiation of strains of T. urticae resistant (R) and susceptible (S) to the acaricides, milbemectin and etoxazol. The R and S strains for milbemectin and etoxazol were irradiated with 200 and 400 Gy of gamma radiation in a Gammacell 220 source to evaluate the effects of gamma radiation on the growth rate of the mites. A dose of 400 Gy totally eliminated populations of both R and S strains of T. urticae within 10 d. A dose of 200 Gy was not sufficient to totally eliminate both T. urticae strains, but it significantly reduced egg viability of both strains. In the most likely measure of efficacy for phytosanitary irradiation of mites—i.e., prevention of F1 egg hatch when parent adults are irradiated—no differences were found in response to irradiation among the 4 strains. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae Koch, is a cosmopolitan mite. It reproduces very rapidly and can also develop resistance to chemicals easily. Vermiwash is the watery extract of vermicomposts, extracted in the presence of rich population of earthworms, with plant growth promoting effects. The study was carried out to determine the efficacy of vermiwash and its combination with acaricide azocyclotin compared to the acaricide alone for control of T. urticae on bean plant under the laboratory and greenhouse conditions. Combinations of vermiwash and the acaricide obviously reduced the population density of T. urticae on bean plant. When the 50% of recommended rate of the acaricide and vermiwash were used, percentage of mortality (100%) of T. urticae was statistically comparable to those with the full rate of acaricide (1 g l −1 ) without vermiwash. It may be suggested that combination of vermiwash with the acaricide can be a promising candidate for biological control of T. urticae on the bean plant reducing the application of the chemical pesticide up to 50%. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite (TSSM) Tetranychus urticae is one of the most important pests of cucurbit plants. If TSSM can act as vector for Acidovorax citrulli (Acc), causal agent of bacterial fruit blotch (BFB), then the movement of mites from infected to healthy plants may represent a potential source of inocula for BFB outbreaks. To confirm the association between Acc and TSSM, we generated a green fluorescent protein-tagged mutant strain (Acc02rf) by transposon mutagenesis and demonstrated that TSSM can transmit Acc from infected to non-infected watermelon plants. Challenge with 10 TSSMs carrying Acc02rf population densities of 1.3 × 10 CFU each on freshly grown individual watermelon plants caused disease transmission to 53 %. Incubation periods ranged 7-9 days. Bacteria recovered from symptoms typical of those associated with leaf necrosis were characterized and identified as Acc. To our knowledge, this is the first report showing that TSSM can be a vector of Acc. The results reported here support that the strong association of TSSM with Acc is of particular importance in controlling BFB. [ABSTRACT FROM AUTHOR]

Neoseiulus womersleyi and N. californicus are two predators that are frequently used to control spider mites in fruit-tree orchards. Neoseiulus womersleyi used to be the dominant predator species in Japan, but since the 1990s in central and southwestern Japan, N. californicus populations have been increasing and have displaced populations of N. womersleyi. We previously observed the same phenomenon under laboratory conditions when these species were released at a 1:1 ratio, and attributed the displacement to asymmetrical intraguild predation. However, the ratio in fruit-tree orchards could be different from 1:1. Therefore, we hypothesized that differential susceptibilities to pesticides might accelerate species displacement of N. womersleyi by N. californicus, even if the ratio between these two species was extremely skewed in favor of N. womersleyi and no species displacement occurred otherwise. We examined the effects of 21 pesticides on egg-to-adult and adult survivorship in N. womersleyi and N. californicus. Among these pesticides, two neonicotinoids (acetamiprid and imidacloprid) had much severer effects on N. womersleyi than on N. californicus and thus could possibly account for the species displacement. When the two species were released onto leaf arenas at an N. californicus: N. womersleyi ratio of 1:9 in the absence of insecticide, no displacement was observed. However, just after acetamiprid or imidacloprid application, the proportion of N. californicus increased, causing N. californicus to displace N. womersleyi. Our results indicate that displacement in predator complexes of fruit-tree orchards could be due to different degrees of pesticide susceptibility. [ABSTRACT FROM AUTHOR]

Systematic research or technical support regarding rubber germplasm resistance against mites was not performed yet. To develop a preliminary understanding of the mite-resistance mechanisms of rubber germplasms, stably resistant rubber germplasms were obtained, the development and reproduction of Eotetranychus sexmaculatus that fed on leaves of resistant and susceptible rubber germplasms were examined in the laboratory, and the activities of protective enzymes in this mite species were also compared. The results indicated that: (1) among the 23 rubber core germplasms identified, five (IRCI12, Reyan87-6-5, IAN717, RRIM600 and RRIC52) steadily developed resistance to E. sexmaculatus; (2) E. sexmaculatus that fed on the highly resistant germplasm IRCI12 did not complete development and reproduction-the female adults laid only 4.90 eggs on average, and none of these eggs hatched; (3) the resistant germplasms extended the duration of each developmental stage, reduced the fecundity, egg hatchability, and female offspring percentage, and significantly decreased the offspring survival rate compared with the susceptible germplasms; and (4) during each developmental stage of the mites that fed on resistant rubber germplasms, decreased activities (by 0.25-fold to 0.63-fold times) of the protective enzymes peroxidase, ascorbate peroxidase, polyphenol oxidase, superoxide dismutase and catalase were observed compared with those in the mites that fed on susceptible rubber germplasms ( P < 0.05). These findings may explain why E. sexmaculatus did not complete their development and reproduction on the resistant rubber germplasms. This study lays a foundation for elucidation of the mechanism of rubber resistance to mites and provides experimental material and technical support for the breeding of mite-resistant rubber plants. [ABSTRACT FROM AUTHOR]

Amblydromalus limonicus (Garman and McGregor) was detected for the first time in 2011 on tomatoes of several locations of the northeastern Spain. During 2012 and 2013 samplings on tomato crop cultivars in the two provinces of Catalonia where the species was found were carried out. The goals of the study were to know the range of spread of the species in these two provinces, its abundance in tomato cultivars, non-crop vegetation among them, in the different parts of the tomato plant and in some other vegetable crops. Results showed that A. limonicus was present at both regions sampled, although there were significant differences in the abundance of the species between sampling points. It is the second in abundance in tomato and the cultivars that most frequently host A. limonicus were Anaidis, Hybrid and Marmande. No significant differences were found in the abundance of A. limonicus among tomato plant canopy strata. On average, it accounted for 31.6 % of all sampled phytoseiids. It was present in four crops (tomato, bean, cucumber and strawberry) and in Amaranthus cruentus, Chenopodium polyspermum, Cynodon dactylon, Mentha sp. , Parietaria officinalis and Phleum pratense. Amblydromalus limonicus is well established in the extreme northeast of Spain all year round in crops and non-crops. [ABSTRACT FROM AUTHOR]

Oribatid mite communities from 18 natural autochthonous forest soils in the Basque Country, belonging to five forest types, distributed along an ombrothermic gradient of five climatic regions were broadly studied. Forest type and climatic region together (45 % of the total variability) were important factors influencing the oribatid community. The local scale variable (forest type, 28 %) was about as determinant a factor as the regional scale (climatic region, 26 %), though together they accounted for just 9 %. By contrast, the influence of spatial distribution (geography) was not significant by itself but played an important role as a co-variable. Differences in community indices were detected only for species abundances, with holm oak showing the highest oribatid density and beech the lowest. The effect of the passage of time on oribatid communities was also analyzed by comparing recent communities to those of 19-26 years ago in the same forests. The community indices are influenced by the course of time when separate periods of time are compared. Although the recently studied forests apparently show the same conservational conditions as those studied in the past, they are less diverse. [ABSTRACT FROM AUTHOR]

The poultry red mite, Dermanyssus gallinae , is an economically important hematophagous parasite of commercial egg laying hens, also affecting domesticated birds and companion animals. Conventional control of D. gallinae through acaricidal spraying is often ineffective, creating an urgent need to identify alternative management strategies for commercial and domestic infestations. Whilst integrated pest management is being considered for D. gallinae , the potential of impeding mite ‘migration’ routes, to either prevent initial infestation or manage established populations, has not been researched. Here we demonstrate that barriers of insecticidal glue, double sided sticky tape and thyme oil can contain D. gallinae within a specified area of a petri dish (78–88% of total mite population) and this level of containment was significantly greater than for negative controls (p values <0.05). Further studies in poultry houses are recommended to investigate the efficacy of these barriers in real world application and identity potential for barriers as a strategy for mite control. [ABSTRACT FROM AUTHOR]

Background: In the northeastern United States, tick-borne diseases are a major public health concern. In controlled studies, a single springtime application of acaricide has been shown to kill 68%-100% of ticks. Although public health authorities recommend use of acaricides to control tick populations in yards, the effectiveness of these pesticides to prevent tick bites or human tick-borne diseases is unknown.Methods: We conducted a 2-year, randomized, double-blinded, placebo-controlled trial among 2727 households in 3 northeastern states. Households received a single springtime barrier application of bifenthrin or water according to recommended practices. Tick drags were conducted 3-4 weeks after treatment on 10% of properties. Information on human-tick encounters and tick-borne diseases was collected through monthly surveys; reports of illness were validated by medical record review.Results: Although the abundance of questing ticks was significantly lower (63%) on acaricide-treated properties, there was no difference between treatment groups in human-tick encounters, self-reported tick-borne diseases, or medical-record-validated tick-borne diseases.Conclusions: Used as recommended, acaricide barrier sprays do not significantly reduce the household risk of tick exposure or incidence of tick-borne disease. Measures for preventing tick-borne diseases should be evaluated against human outcomes to confirm effectiveness. [ABSTRACT FROM AUTHOR]

An organic product based on oxalic acid was evaluated for use in Varroa control under spring/summer climatic conditions in Argentina. The formulation consists of four strips made of cellulose impregnated with a solution based on oxalid acid. Forty-eight beehives were used to assess the product efficacy. Residues of the product were also tested in honey, bees, and wax. Each trial had respective control groups without oxalic treatment. At the beginning of the experiment, four strips of the formulation were applied to the colonies belonging to the treated group. Falling mites were counted after 7, 14, 21, 28, 35, and 42 days. After the last count, the strips were removed and colonies received two flumethrin strips for 45 days. Falling mites were counted throughout this period. Average efficacy of the organic product was 93.1 % with low variability. This product is an organic treatment designed for Varroa control during brood presence and represents a good alternative to the synthetic treatments. [ABSTRACT FROM AUTHOR]

The present review aims to identify the phytosanitary risk, the dissemination pathways and the possible control methods of Aceria kuko, the goji-berries gall mite, which was imported to Europe from China via orders by mail in 2007. Despite the first eradicative measures taken by the UK in 2008 and Germany in 2011, the pest was found again in Germany (2012), in Slovenia (2012), in Cyprus (2013), in Romania (2013), in Hungary (2014) and in Serbia (2015). Although the import of Solanaceae intended for planting is prohibited in Europe, the parcels ordered by mail escape the pest and disease control services. Our field observations regarding the attack frequency, attack intensity and the losses indicate that Aceria kuko is a potential threat for goji growers. Monitoring the presence of the mite in the Romanian Goji plantations should therefore be regarded as a biosafety measure not only for Romania, but for entire Europe. [ABSTRACT FROM AUTHOR]

Reducing the losses caused by Aceria guerreronis Keifer has been an arduous task for farmers. However, there are no detailed studies on losses that simultaneously analyse correlated parameters, and very few studies that address the economic viability of chemical control, the main strategy for managing this pest. In this study the objectives were (1) to estimate the crop loss due to coconut mite and (2) to perform a financial analysis of acaricide application to control the pest. For this, the following parameters were evaluated: number and weight of fruits, liquid albumen volume, and market destination of plants with and without monthly abamectin spraying (three harvests). The costs involved in the chemical control of A. guerreronis were also quantified. Higher A. guerreronis incidence on plants resulted in a 60 % decrease in the mean number of fruits harvested per bunch and a 28 % decrease in liquid albumen volume. Mean fruit weight remained unaffected. The market destination of the harvested fruit was also affected by higher A. guerreronis incidence. Untreated plants, with higher A. guerreronis infestation intensity, produced a lower proportion of fruit intended for fresh market and higher proportions of non-marketable fruit and fruit intended for industrial processing. Despite the costs involved in controlling A. guerreronis, the difference between the profit from the treated site and the untreated site was 18,123.50 Brazilian Real; this value represents 69.1 % higher profit at the treated site. [ABSTRACT FROM AUTHOR]

BACKGROUND The two-spotted mite, Tetranychus urticae Koch, is one of the most serious mite pests of crops throughout the world. Biocontrol of the mite with fungal agents has long been paid much attention because of the development of insecticide resistance and the severe restriction of chemical pesticides. In this study, the efficacy of submerged conidia of the entomopathogenic fungus Isaria cateniannulata strain 08XS-1 against T. urticae eggs, larvae and female adults was evaluated at different temperatures and humidity in the laboratory and under field conditions. RESULTS The results showed that a suspension of 2 × 107 submerged conidia mL−1 caused the highest mortalities of mite eggs, larvae and females (100, 100 and 70% respectively) at 100% relative humidity and 25 °C in the laboratory. In the field experiments against the mites, a suspension of 2 × 108 submerged conidia mL−1 achieved significant efficiency - the relative control effects were 88.6, 83.8 and 83%, respectively, in cucumber, eggplant and bean fields after 10 days of treatment. CONCLUSION The results suggest that the I. cateniannulata strain 08XS-1 is a potential fungal agent, with acceptable production cost of conidia, against T. urticae in the field in an area such as southwestern China with higher air humidity. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study illustrates a novel strain (designated as BPU5) of Bacillus thuringiensis ( Bt) isolated from the rumen of Malabari goat, capable of producing polymorphic δ-endotoxin crystals concomitantly with sporulation in Luria-Bertani medium ( LB), and the δ-endotoxin was efficient to combat Tetranychus macfarlanei, a devastating mite. Polymorphic δ-endotoxin crystals produced were assessed by scanning electron microscopy and monitored its production concomitantly with sporulation in LB with or without sugar supplements. Toxicity of the δ-endotoxin was assessed on T. macfarlanei using leaf disc bioassay method. Mortality rate was determined by comparing the survival of mites on the diet (prepared in 10% sucrose and powdered rice husk) containing different concentrations (1-10 mg/ml) of 72-h-old crude pellet (dried mixture of δ-endotoxin (17 mg/g pellet), endospores and a few vegetative cells) or control diet with autoclaved pellet. The maximum production (1.39 mg/ml) of δ-endotoxin was observed at 72 h in LB. Among the sugars (glucose, sucrose, maltose or lactose) tested as additional carbon source, glucose (8 g/l) enhanced (1.82 mg/ml) the production of δ-endotoxin by 30%. The lethal concentration ( LC50) required to kill 50% mites was estimated as 8.024 mg/ml. The δ-endotoxin produced by B. thuringiensis BPU5 is shown to efficiently combat T. macfarlanei, a devastating mite infesting agricultural fields. [ABSTRACT FROM AUTHOR]

BACKGROUND Camptothecin ( CPT), a monoterpene indole alkaloid from Camptotheca acuminate (Nyssaceae), is toxic to some insect pests but insoluble in water. Here we show that an aqueous CPT-Na+ solution can kill the phytophagous mites Tetranychus urticae ( TU), Acaphylla theae ( AT) and Brevipalpus obovatus ( BO) under laboratory and field conditions. RESULTS Modelling of 10 day time-concentration-mortality responses of female adults to 2 mL tower sprays of three CPT-Na+ dilutions generated LC50 and LT50 values that decreased over post-spray days and sprayed amounts respectively. CPT-Na+ sprays required to kill 50% BO, TU and AT were 35, 41 and 124 µg mL−1 on day 1 post-spray, but rapidly decreased to 2.2, 2.5 and 3.6 µg mL−1 on day 5, and to 0.69, 0.77 and 1.17 µg mL−1 on day 7 respectively. In summer field trials, a spray rate of 7.5 g CPT-Na+ ha−1 provided better control efficacy against TU (81-85%) on cotton or AT (90-93%) and BO (83-88%) in tea gardens than aramite (commercial acaricide) at the labelled rate of 56.25 g ha−1. Half of the CPT-Na+ rate controlled the mites as effectively as aramite. CONCLUSION Water-soluble CPT-Na+ is a promising plant-sourced acaricide to combat wide-spectrum pest mites. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Ear mites (Otodectes cynotis) and ear canal tumors are highly prevalent among federally endangered Island foxes (Urocyon littoralis catalinae) living on Santa Catalina Island off the coast of Southern California. Since studies began in the 1990s, nearly all foxes examined were found to be infected with ear mites, and ceruminous gland tumors (carcinomas and adenomas) were detected in approximately half of all foxes ≥ 4 years of age. We hypothesized that reduction of ear mite infection would reduce otitis externa and ceruminous gland hyperplasia, a risk factor for tumor development. In this study, we conducted a randomized field trial to assess the impact of acaricide treatment on ear mite prevalence and intensity of infection, otitis externa, ceruminous gland hyperplasia, and mite-specific IgG and IgE antibody levels. Treatment was highly effective at eliminating mites and reducing otitis externa and ceruminous gland hyperplasia, and mite-specific IgG antibody levels were significantly lower among uninfected foxes. Ceruminous gland hyperplasia increased in the chronically infected, untreated foxes during the six month study. Our results provide compelling evidence that acaricide treatment is an effective means of reducing ear mites, and that mite removal in turn reduces ear lesions and mite-specific IgG antibody levels in Santa Catalina Island foxes. This study has advanced our understanding of the underlying pathogenesis which results in ceruminous gland tumors, and has helped inform management decisions that impact species conservation. [ABSTRACT FROM AUTHOR]

Brevipalpus mites (Acari: Tenuipalpidae) carrying citrus leprosis virus are considered serious quarantine pests. The objective of this research was to clarify the effectiveness of commonly used fruit cleaners, soaps, waxes, and mechanical brushing techniques (alone and in combination) on removal and/or mortality of mites (percentage of density reduction) from infested citrus fruits. Six bioassays were conducted with infested lemons, Citrus limon (L.) Burm.f. (Sapindales: Rutaceae), using non-virulent Brevipalpus yothersi Baker as a model species. In each bioassay, all stages (eggs, nymphs, and adults) of B. yothersi were recorded before and after treatment. Results indicated that none of the treatments provided 100% reduction of all stages of mites, as would be required for quarantine treatments. In general, mite reduction following single treatments (soap rinse, brushing, or waxing alone) was not significantly different from reduction obtained with a water drench control. However, several combination treatments were successful in achieving ~90% reduction of mites, particularly those that included application of a food-grade wax coating. Therefore, a combination of treatments, including a soap wash and mechanical brushing followed by a wax coating, may be the most effective method to achieve significant reduction of all stages of Brevipalpus mites from infested citrus. [ABSTRACT FROM AUTHOR]

Due to the withdrawal from the plant protection industry of several main insecticides (e.g. endosulfan, amitraz and propargite) commonly used to control the strawberry mite ( Phytonemus pallidus spp . fragariae ), there is a constant need to search for new control measures against this pest. The efficacy of spirotetramat (Movento 150 OD at rates of 0.5 and 0.7 and Movento 100 SC at rates of 0.75 and 1.0 l ha −1 ), abamectin (Vertimec 018 EC, 1.0 l ha −1 ) and abamectin (1.0 l ha −1 ) + the adjuvant Slippa (0.2 l ha −1 ) for control of strawberry mite was evaluated in the current study. Pyridaben (Sanmite 20 WP, 2.25 kg ha −1 ) was used as a reference product. All of the products were used twice at weekly intervals, after fruit harvest, when the population of P. pallidus exceeded the risk threshold. All products significantly reduced P. pallidus populations in strawberry plantations compared to control plots. The results obtained with spirotetramat were dependent on dose and formulation, and ranged from 60% to over 90% efficacy. The efficacy of abamectin for controlling the mobile forms of strawberry mite was 81–99%. This active ingredient applied in combination with the adjuvant did not display any better level of control than when applied alone (efficacy 77–95%). The results obtained with the reference product (pyridaben) were similar or slightly lower (average > 80%) than those obtained with the test products. [ABSTRACT FROM AUTHOR]

The Varroa mite ( Varroa destructor) is implicated as a major disease factor in honey bee ( Apis mellifera) populations worldwide. Honey bees are extensively relied upon for pollination services, and in countries such as New Zealand and Australia where honey bees have been introduced specifically for commercial pollinator services, the economic effects of any decline in honey bee numbers are predicted to be profound. V. destructor established in New Zealand in 2000 but as yet, Australia remains Varroa-free. Here we analyze the history of V. destructor invasion and spread in New Zealand and discuss the likely long-term impacts. When the mite was discovered in New Zealand, it was considered too well established for eradication to be feasible. Despite control efforts, V. destructor has since spread throughout the country. Today, assessing the impacts of the arrival of V. destructor in this country is compromised by a paucity of data on pollinator communities as they existed prior to invasion. Australia's Varroa-free status provides a rare and likely brief window of opportunity for the global bee research community to gain understanding of honey bee-native pollinator community dynamics prior to Varroa invasion. [ABSTRACT FROM AUTHOR]

The effective dose of irradiation to control pest mites in quarantine has been studied extensively, but the molecular mechanisms underlying the effects of the irradiation on mites are largely unknown. In this study, exposure to 400 Gy of γ rays had significant (p < 0.05) effects on the adult survival, fecundity and egg viability of Panonychus citri. The irradiation caused the degradation of the DNA of P. citri adults and damaged the plasma membrane system of the egg, which led to condensed nucleoli and gathered yolk. Additionally, the transcriptomes and gene expression profiles between irradiated and non-irradiated mites were compared, and three digital gene expression libraries were assembled and analyzed. The differentially expressed genes were putatively involved in apoptosis, cell death and the cell cycle. Finally, the expression profiles of some related genes were studied using quantitative real-time PCR. Our study provides valuable information on the changes in the transcriptome of irradiated P. citri, which will facilitate a better understanding of the molecular mechanisms that cause the sterility induced by irradiation. [ABSTRACT FROM AUTHOR]

The article discusses the development of two spotted spider mite Tetranychus urticae Koch in different temperatures. The phytophagy in Acari is seen in Tetranychidae, Tenuipalpidae, Tarsonemidae, Eriophyidae and Tuckerellidae. Topics include effects of temperature in mites on host plants, analysis of variance (ANOVA), and reproduction and further development of spider mites.

the level of development of russet mite in various plants and the amount of insectacaricide used for these pests and their biological efficacy has been studied. Moreover, based on these result, recommendation have been made for commercial grower. [ABSTRACT FROM AUTHOR]

Invasive parasites are major threats to biodiversity. The honey bee ectoparasite, Varroa destructor , has shifted host and spread almost globally several decades ago. This pest is generally considered to be the main global threat to Western honey bees, Apis mellifera , although the damages it causes are not equivalent in all its new host's populations. Due to the high virulence of this parasite and the viruses it vectors, beekeepers generally rely on acaricide treatments to keep their colonies alive. However, some populations of A. mellifera can survive without anthropogenic mite control, through the expression of diverse resistance and tolerance traits. Such surviving colonies are currently found throughout the globe, with the biggest populations being found in Sub-Saharan Africa and Latin America. Recently, genetic differences between mite populations infesting surviving and treated A. mellifera colonies in Europe were found, suggesting that adaptations of honey bees drive mite evolution. Yet, the prevalence of such co-evolutionary adaptations in other invasive populations of V. destructor remain unknown. Using the previous data from Europe and novel genetic data from V. destructor populations in South America and Africa, we here investigated whether mites display signs of adaptations to different host populations of diverse origins and undergoing differing management. Our results show that, contrary to the differences previously documented in Europe, mites infesting treated and untreated honey bee populations in Africa and South America are genetically similar. However, strong levels of genetic differentiation were found when comparing mites across continents, suggesting ongoing allopatric speciation despite a recent spread from genetically homogenous lineages. This study provides novel insights into the co-evolution of V. destructor and A. mellifera , and confirms that these species are ideal to investigate coevolution in newly established host-parasite systems. • Varroa destructor parasites show genetic differences across novel host populations. • Differences can be found in some sympatric populations with different management. • Comparing allopatric populations also revealed ongoing genetic differentiation. • Interactions with distinct host populations appear to drive V. destructor evolution. [ABSTRACT FROM AUTHOR]

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

Honey bees are exposed to various pesticides through pollinating and in-hive Varroa mite control. The most basic method for evaluating pesticide toxicity is the indoor bioassay using worker bees, in which newly emerged adults are matured in incubators for conditioning before use. However, little information is available on the optimum maturation temperature from a toxicological point of view, even though it can affect honey bee responses to pesticides. In this paper, to evaluate the optimal maturation temperature for pesticide toxicity testing, several indices related to the development, gene transcription, and toxicological properties of honey bee adults following maturation at 25, 30, and 35 °C were compared with those of field bees. The body weight and developmental state of hypopharyngeal glands were highest in the bees matured at 30 °C, and the overall transcription profiles of detoxification-related genes in the field bees were closest to those of bees matured at 30 °C, whereas immaturity and features of thermal stress were observed in the 25 °C and 35 °C bee groups, respectively. In the bioassay results, the effects of maturation temperature on the toxic response of honey bees varied significantly depending on the type of pesticide. By considering all the biological and toxicological aspects examined, we confirmed that 30 °C is a recommended maturation temperature for adult honey bee toxicity test. [Display omitted] • Honey bees maturing at 25, 30, and 35 °C were compared with field bees. • Hypopharyngeal gland development and body weight were highest in the 30 °C bees. • Transcription profiles of the 30 °C bees were closest to those of the field bees. • Toxicological responses were different depending on the kinds of acaricides. • 30 °C is recommended as a maturation temperature for the worker bee toxicity test. [ABSTRACT FROM AUTHOR]

Varroosis is a disease caused by the mite Varroa destructor , and it is considered one of the biggest threats to honey bee populations globally. Mite control is centered on the use of synthetic acaricides, such as amitraz and flumethrine. However, high usage of these chemicals is associated with a wide variety of undesirable effects on bee colonies, including the development of resistance and persistence of harmful residues of acaricides in hive products used by humans. Botanical extracts have been identified as a potentially suitable organic alternative to synthetic acaricides. Essential oils, such as clove, eucalyptus, lemongrass, and oregano, have been found to exhibit acaricidal activity against V. destructor. The main goal of this work was to assess the bioactivity of the Cymbopogon nardus essential oil from two different locations (Argentina and India), and the activity of its major component the monoterpene citronellal. According to our results, complete essential oil from India is more effective in controlling parasitosis than the isolated citronellal component. The essential oil of C. nardus from Argentina demonstrated promise for the control of varroosis, as well as exhibiting low toxicity against bees (LC 50 = 11.84 μL/mL). In addition, this essential oil may avoid the problems caused by synthetic acaricides, such as the emergence of resistance foci in Varroa and residues in hive products. Future research needs to investigate the delivery of volatile essentials oils to target mite populations. [Display omitted] • Promising bioactivity of Cymbopogon nardus essential oils against Varroa destructor. • Differential toxicity according to the origin of the essential oil in Apis mellifera. • Essential oils have better bioactivity than the major isolated components citronellal. [ABSTRACT FROM AUTHOR]

This is the first study to investigate the activity of thymol on Rhipicephalus microplus larvae under semi-natural conditions. For this purpose, tests were conducted in pots with Brachiaria decumbens seedlings containing cattle tick larvae. Thymol, diluted in ethanol 50° GL, was tested at concentrations of 2.5, 5.0, 10.0, 15.0, and 20.0 mg/mL, along with the control group treated with the solvent alone. Each treatment was composed of five pots (1 pot = a repetition). The experiment was performed in three steps. On the first day, the larvae were applied at the base of the signalgrass. Twenty-four hours later, approximately 25 mL of the solution was applied with thymol on the top of the vegetation in each pot. The survival of the larvae was measured 24 h after application of the solutions. Each pot was analyzed individually, and the grass fillets contained larvae were cut with scissors, placed in Petri dishes, and taken to the laboratory to count the number of living larvae. At the highest concentrations (10, 15, and 20 mg /mL), the number of live larvae declined by more than 95 % in relation to the control group. The lethal concentration 50 % (LC50) and LC90 values were 3.45 and 9.25 mg/ml, respectively. The application of thymol in semi-natural conditions starting concentration of 10 mg/mL significantly reduced the number of living R. microplus larvae. [ABSTRACT FROM AUTHOR]

Galendromus occidentalis (Nesbitt) is an important biological control agent of spider mites (Acari: Tetranychidae) in Washington apple orchards. It was thought to be essentially the sole phytoseiid existing in this system, due in part to its resistance to commonly used orchard pesticides, and organophosphates in particular. To test this assumption, we conducted a survey of 102 commercial apple blocks in Washington to characterize the community of phytoseiid species. Seven phytoseiid species were found in our samples; G. occidentalis and Amblydromella caudiglans (Schuster) were found in the greatest abundance. We hypothesized that the gradual shift away from the use of organophosphates in recent decades may have caused the change in phytoseiid community structure. The survey data and information regarding the management, location, and surrounding habitat of each block were used to determine what factors affect phytoseiid abundances. Galendromus occidentalis abundance was positively affected by the use of conventional (vs. organic) spray programs, and the use of the acaricide bifenazate. Amblydromella caudiglans abundance was negatively affected by bifenazate use and positively affected by herbicide strip weediness; it was also less prevalent in 'Golden Delicious' blocks compared to other cultivars. These results indicate that A. caudiglans reaches higher abundances in orchards that lack certain agricultural disturbances, whereas G. occidentalis can survive in more disturbed environments. Surveys of this nature can provide valuable insight to potential drivers of community structure, allowing for the improvement of integrated pest management programs that incorporate conservation of newly recognized biological control agents such as A. caudiglans. [ABSTRACT FROM AUTHOR]

The successful integrated mite management program for Washington apples was based on conservation of the mite predator Galendromus occidentalis (Nesbitt). In the 1960s, this mite was assumed to be the only phytoseiid in Washington commercial apple orchards, due to its preference for the most common mite pest of that period, Tetranychus mcdanieli McGregor, as well as its resistance to organophosphate pesticides. A recent survey of phytoseiids in Washington apple found that another phytoseiid, Amblydromella caudiglans (Schuster) has become common. It is a more generalized predator than G. occidentalis (it is not a Tetranychus spp. specialist) and is not known to be organophosphate-resistant. A series of experiments was conducted to compare the life history, prey consumption, and pesticide tolerance of these two species. Galendromus occidentalis developed more quickly than A. caudiglans, but had slightly lower egg survival. Although A. caudiglans attacked more Tetranychus urticae Koch eggs than G. occidentalis, it could not reproduce on this diet. Both predators performed equally well on a diet of T. urticae protonymphs. Unlike G. occidentalis, A. caudiglans experienced significant mortality when exposed to carbaryl, azinphosmethyl, and bifenazate. Both predators experienced significant mortality due to imidacloprid and spinetoram. These results highlight the key differences between these two predators; the shift away from organophosphate use as well as the change in dominant mite pest to Panonychus ulmi (Koch) may be driving factors for the observed increased abundance of A. caudiglans in Washington apple. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the effects of honey bees ( Apis mellifera L.) with different grooming ability and queen pheromone status on mortality rates of Varroa mites ( Varroa destructor Anderson and Trueman), mite damage, and mortality rates of honey bees. Twenty-four small queenless colonies containing either stock selected for high rates of mite removal (n = 12) or unselected stock (n = 12) were maintained under constant darkness at 5 °C. Colonies were randomly assigned to be treated with one of three queen pheromone status treatments: (1) caged, mated queen, (2) a synthetic queen mandibular pheromone lure (QMP), or (3) queenless with no queen substitute. The results showed overall mite mortality rate was greater in stock selected for grooming than in unselected stock. There was a short term transitory increase in bee mortality rates in selected stock when compared to unselected stock. The presence of queen pheromone from either caged, mated queens or QMP enhanced mite removal from clusters of bees relative to queenless colonies over short periods of time and increased the variation in mite mortality over time relative to colonies without queen pheromone, but did not affect the proportion of damaged mites. The effects of source of bees on mite damage varied with time but damage to mites was not reliably related to mite mortality. In conclusion, this study showed differential mite removal of different stocks was possible under low temperature. Queen status should be considered when designing experiments using bioassays for grooming response. [ABSTRACT FROM AUTHOR]

Background: This laboratory study compared the efficacy of Bravecto™ (fluralaner), formulated as a chewable tablet, with the efficacy of Advocate® (imidacloprid/moxidectin), formulated for topical administration, against naturally acquired generalized demodicosis in dogs. Methods: Sixteen dogs, all diagnosed with generalized demodectic mange, were randomly allocated to two equal groups. Bravecto™ chewable tablets were administered once orally at a minimum dose of 25 mg fluralaner/kg body weight to one group of dogs, while the second group was treated topically on three occasions at 28-day intervals with Advocate® at a minimum dose of 10 mg imidacloprid/kg body weight and 2.5 mg moxidectin/kg body weight. Mites were counted in skin scrapings and demodectic lesions were evaluated on each dog before treatment and at 28-day intervals thereafter over a 12 week study period. Deep skin scrapings (∼4 cm2) were made from the same five sites on each dog at each subsequent examination. Results: After single oral administration of Bravecto™ chewable tablets, mite numbers in skin scrapings were reduced by 99.8% on Day 28 and by 100% on Days 56 and 84. Mite numbers in the dogs treated topically on three occasions at 28-day intervals with Advocate® were reduced by 98.0% on Day 28, 96.5% on Day 56 and by 94.7% on Day 84. Statistically significantly (P ≤ 0.05) fewer mites were found on Days 56 and 84 on the Bravecto™ treated dogs compared to Advocate® treated dogs. A marked decrease was observed in the occurrence of erythematous patches, crusts, casts and scales in the dogs treated with Bravecto™ and in the occurrence of erythematous patches in the dogs treated with Advocate®. With the exception of one dog in each treated group, all dogs exhibited hair regrowth ≥ 90% at the end of the study in comparison with their hair-coat at study start. Conclusions: Single oral administration of Bravecto™ chewable tabletsishighlyeffective against generalized demodicosis, with no mites detectable at 56 and 84 days following treatment. In comparison, Advocate®, administered three times at 28-day intervals, is also highly effective against generalized demodicosis, but most dogs still harboured mites at all assessment time points. Both treatments resulted in a marked reduction of skin lesions and increase of hair re-growth 12 weeks after the initial treatment. [ABSTRACT FROM AUTHOR]

The impact of the fungicides mancozeb, myclobutanil, and meptyldinocap on populations of Typhlodromus pyri Scheuten was evaluated under field conditions, when applied following the good agricultural practices recommended for their use. Two complementary statistical models were used to analyze the population reduction compared to the control: a linear mixed model to estimate the mean effect of the fungicide, and a generalized linear mixed model (proportional odds mixed model) to estimate the cumulative probability for those effects being equal or less than a specific IOBC class (International Organization for Biological and Integrated Control of Noxious Animal and Plants). Findings from 27 field experiments in a range of different vine-growing regions in Europe indicated that the use of mancozeb, myclobutanil, and meptyldinocap caused minimal impact on naturally occurring populations of T. pyri. Both statistical models confirmed that although adverse effects on T. pyri can occur under certain conditions after several applications of any of the three fungicides studied, the probability of the effects occurring is low and they will not persist. These methods demonstrated how data from a series of trials could be used to evaluate the variability of the effects caused by the chemical rather than relying on the worst-case findings from a single trial. [ABSTRACT FROM AUTHOR]

The production and uptake of yolk protein play an important role in the reproduction of all oviparous organisms. Vitellogenin (Vg) is the precursor of vitellin (Vn), which is the major egg storage protein, and vitellogenin receptor (VgR) is a necessary protein for the uptake of Vg into developing oocytes. In this paper, we characterize the full-length Vg and VgR, PcVg1 and PcVgR, respectively, of the citrus red mite Panonychus citri (McGregor). The PcVg1 cDNA is 5748 nucleotides (nt) with a 5553-nt open reading frame (ORF) coding for 1851 amino acids (aa), and the PcVgR is 6090 nt, containing an intact ORF of 5673 nt coding an expected protein of 1891 aa. The PcVg1 aa sequence shows a typical GLCG domain and several K/RXXR cleavage sites, and PcVgR comprises two ligand-binding domains, two epidermal growth factor (EGF)-like regions containing YWTD motifs, a transmembrane domain, and a cytoplasmic domain. An analysis of the aa sequences and phylogenetics implied that both genes were genetically distinct from those of ticks and insects. The transcriptional profiles determined by real-time quantitative PCR in different developmental stages showed that both genes present the same expressional tendencies in eggs, larvae, nymphs, and adults. This suggested that the biosynthesis and uptake of PcVg occurs coordinately. The strong reproductive capacity of P. citri has been hypothesized as an important factor in its resistance; consequently, understanding the molecular mechanisms regulating Vg and VgR are fundamental for mite control. [ABSTRACT FROM AUTHOR]

Background: The Western honey bee (Apis mellifera L.) is a critical component of human agriculture through its pollination activities. For years, beekeepers have controlled deadly pathogens such as Paenibacillus larvae, Nosema spp. and Varroa destructor with antibiotics and pesticides but widespread chemical resistance is appearing and most beekeepers would prefer to eliminate or reduce the use of in-hive chemicals. While such treatments are likely to still be needed, an alternate management strategy is to identify and select bees with heritable traits that allow them to resist mites and diseases. Breeding such bees is difficult as the tests involved to identify disease-resistance are complicated, time-consuming, expensive and can misidentify desirable genotypes. Additionally, we do not yet fully understand the mechanisms behind social immunity. Here we have set out to discover the molecular mechanism behind hygienic behavior (HB), a trait known to confer disease resistance in bees. Results: After confirming that HB could be selectively bred for, we correlated measurements of this behavior with protein expression over a period of three years, at two geographically distinct sites, using several hundred bee colonies. By correlating the expression patterns of individual proteins with HB scores, we identified seven putative biomarkers of HB that survived stringent control for multiple hypothesis testing. Intriguingly, these proteins were all involved in semiochemical sensing (odorant binding proteins), nerve signal transmission or signal decay, indicative of the series of events required to respond to an olfactory signal from dead or diseased larvae. We then used recombinant versions of two odorant-binding proteins to identify the classes of ligands that these proteins might be helping bees detect. Conclusions: Our data suggest that neurosensory detection of odors emitted by dead or diseased larvae is the likely mechanism behind a complex and important social immunity behavior that allows bees to co-exist with pathogens. [ABSTRACT FROM AUTHOR]

Symbiotic root micro-organisms such as arbuscular mycorrhizal fungi commonly change morphological, physiological and biochemical traits of their host plants and may thus influence the interaction of aboveground plant parts with herbivores and their natural enemies. While quite a few studies tested the effects of mycorrhiza on life history traits, such as growth, development and reproduction, of aboveground herbivores, information on possible effects of mycorrhiza on host plant choice of herbivores via constitutive and/or induced plant volatiles is lacking. Here we assessed whether symbiosis of the mycorrhizal fungus Glomus mosseae with common bean plants Phaseolus vulgaris influences the response of the two-spotted spider mite Tetranychus urticae to volatiles of plants that were clean or infested with spider mites. Mycorrhiza-naïve and -experienced spider mites, reared on mycorrhizal or non-mycorrhizal bean plants for several days before the experiments, were subjected to Y-tube olfactometer choice tests. Experienced but not naïve spider mites distinguished between constitutive volatiles of clean non-mycorrhizal and mycorrhizal plants, preferring the latter. Neither naïve nor experienced spider mites distinguished between spider mite-induced volatiles of mycorrhizal and non-mycorrhizal plants. Learning the odor of clean mycorrhizal plants, resulting in a subsequent preference for these odors, is adaptive because mycorrhizal plants are more favorable host plants for fitness of the spider mites than are non-mycorrhizal plants. [ABSTRACT FROM AUTHOR]

There are an estimated 0.5–1 million mite species on earth. Among the many mites that are known to affect humans and animals, only a subset are parasitic but these can cause significant disease. We aim here to provide an overview of the most recent work in this field in order to identify common biological features of these parasites and to inform common strategies for future research. There is a critical need for diagnostic tools to allow for better surveillance and for drugs tailored specifically to the respective parasites. Multi-‘omics’ approaches represent a logical and timely strategy to identify the appropriate mite molecules. Recent advances in sequencing technology enable us to generate de novo genome sequence data, even from limited DNA resources. Consequently, the field of mite genomics has recently emerged and will now rapidly expand, which is a particular advantage for parasitic mites that cannot be cultured in vitro. Investigations of the microbiota associated with mites will elucidate the link between parasites and pathogens, and define the role of the mite in transmission and pathogenesis. The databases generated will provide the crucial knowledge essential to design novel diagnostic tools, control measures, prophylaxes, drugs and immunotherapies against the mites and associated secondary infections. [ABSTRACT FROM AUTHOR]