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Chaetodactylus krombeini (Acariformes: Astigmata: Chaetodactylidae) mites are kleptoparasites of solitary bees in the genus Osmia and depend on bee hosts for harbourage, nutrition, and dispersal, with infestations increasing morbidity and larval mortality. The life history traits of C. krombeini are unclear, complicating the control efforts of mites in managed bee nests. Mites in the family Chaetodactylidae have a facultative life stage, the heteromorphic deutonymph, used for either dispersal or dormancy when food resources are sparse. The heteromorphic deutonymph life stage is hypothesized to consist only of females, requiring arrhenotokous parthenogenesis to reproduce. This study examined this hypothesis by determining the sex of the adults that developed from each deutonymph morph. Phoretic deutonymphs were isolated after overwintering either with or without a bee host; inert deutonymphs were isolated from field collections from various locations. Mites were individually observed for 14 days, and development was recorded. Mites that reached adulthood were sexed. After 14 days, 32–38% of heteromorphic deutonymphs that reached adulthood were male. These results disprove the previous hypothesis that heteromorphic deutonymphs are exclusively female. The survival and reproductive strategies of C. krombeini are now in question, specifically the role of true arrhenotoky in founding new mite populations. [ABSTRACT FROM AUTHOR]

Different plant part extracts of cherry laurel [Prunus laurocerasus (Rosaceae)] were investigated for the acaricidal and repellent activity against Polyphagotarsonemus latus (Prostigmata: Tarsonemidae). The leaf, flower, and seed aqueous extracts of cherry laurel were prepared for efficacy bioassays. The tested concentrations of each extract were 1% (volume/volume, v/v), 5% (v/v), 10% (v/v), 20% (v/v) and 30% (weight/volume, w/v). Distilled water and a mixed formulation of 228.6 g/L spiromesifen + 11.4 g/L abamectin were used as negative and positive controls, respectively. It can be concluded that the flower and leaf extract of P. laurocerasus at 30% concentration and the seed extract at 10% or greater concentrations have the potential to control P. latus in the egg stage. Although spiromesifen+abamectin caused extremely low egg mortality (9.5%), all larvae died shortly after hatching (indirect ovicidal effect). In contrast, all adult mites died within 20 hours after spraying. Moreover, the adult mortalities (92%-98%) associated with seed extract at 30% during the experimental period, and the leaf (93.78%) and flower (91.11%) extract at 30% 72-h after exposure were statistically similar to that of spiromesifen+abamectin (100%) application. All extracts at 20% and seed extract at 10% or greater concentrations may also have a great potential for repelling P. latus. [ABSTRACT FROM AUTHOR]

Panonychus citri (McGregor) is one of the most destructive pests of citrus trees. Its control is difficult because it has developed resistance to some synthetic pesticides. GC-mite is a novel botanical pesticide based on cottonseed, clove, and garlic oils that has shown the potential to control tetranychid mites. This study aimed to evaluate the effects of sublethal concentrations of GC-mite on the life history and biochemical parameters of P. citri. Age-stage life table procedure was used to evaluate the effects of two sublethal concentrations (LC20 = 59.40 μg ml−1 and LC30 = 78.66 μg ml−1) of GC-mite on the development, longevity, and reproduction of P. citri. The biochemical analysis included the content of lipids, carbohydrates and glycogen, esterase, and glutathione S-transferase (GST) activities. The developmental time of treated mites with LC30 was significantly longer than the control but the adult longevity and oviposition days of P. citri treated with both sublethal concentrations decreased. The total fecundity of treated mites decreased with increasing GC-mite concentration applied. The life table analysis showed that sublethal concentrations of GC-mite significantly affected gross reproductive rate (GRR), net reproductive rate (R0), intrinsic rate of increase (r), and mean generation time (T). The estimated values of r were significantly lower than the control in LC20 (0.130 day−1) and LC30 (0.117 day−1). The lipids, carbohydrates and glycogen contents as well as esterase and GST activities were significantly lower in mites treated with LC30 concentration, but no significant effect was found in mites treated with LC20 and control. These results suggest that sublethal concentrations of GC-mite had significant effects on both demographic and biochemical parameters of P. citri. [ABSTRACT FROM AUTHOR]

The predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is a key natural enemy applied in phytophagous mite control in agricultural production areas. This study is aimed at investigating the development of pyridaben resistance as a result of the selection pressure under laboratory conditions on N. californicus mites, the inheritance of pyridaben resistance in this predatory mite, and the relationship of resistance with target region mutations. Pyridaben resistance levels were evaluated using a leaf disc spraying tower method. As a result of seven selections, 270-fold pyridaben resistance was identified in N. californicus. As a result of inheritance studies, pyridaben resistance in F1 females resulted from incomplete dominance and sex. Neoseiulus californicus was resistant to pyridaben and there was no significant difference in the monooxygenase enzyme levels in respect to the initial population. No amino acid changes were detected in the PCR evaluations of target site mutations in the pyridaben-resistant and initial populations of N. californicus. Increased pyridaben resistance in the selected population was thought to be caused by more mechanisms other than target site mutations. [ABSTRACT FROM AUTHOR]

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

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

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

Despite their great importance in the biological control of phytophagous mites and insects, nothing is known with regard to the phytoseiid mite fauna in Ethiopia. In this paper, three species, Amblyseius chanioticus Papadoulis, Graminaseius shwelei El-Banhawy & Knapp and Neoseiulus scapilatus (van der Merwe) are reported for the first time from Ethiopia. Because the original description of G. shwelei was based on a single female specimen, this species is redescribed based on females to provide intraspecific variation and to improve its diagnosis. In addition, the male G. shwelei is described for the first time. Furthermore, short descriptions of A. chanioticus and N. scapilatus are also given. [ABSTRACT FROM AUTHOR]

The organic extract of the aerial parts of Dittrichia viscosa, a perennial native plant of the Mediterranean basin, showed a significant acaricidal activity against Varroa destructor, the parasite mite of Apis mellifera, commonly called honey bee. Among the metabolites isolated from the organic extract of this Asteraceae, α-costic acid showed to be one of the compounds responsible for the toxic activity exhibited by the crude plant extract on this parasite mite species. In addition to the toxic effect a clear acaricidal response has been recorded when the parasitic mite was exposed to 1 mg/mL concentration of α-costic acid while no effects have been showed on honey bees using the same compound at the same concentration. This finding suggests a potential use of α-costic acid to control Varroa mites. The possibility to reliably achieve absolute configuration of α-costic acid by DFT computational analysis of chiroptical spectra has been also demonstrated.† [ABSTRACT FROM AUTHOR]

Oligonychus ilicis (McGregor) (Acari: Tetranychidae), is one of the most important mite pests found in coffee plants. One way to reduce intensive pest attacks is management via resistant plants. The purpose of this study was to evaluate the resistance of 14 C. canephora genotypes to O. ilicis by antixenosis and antibiosis mechanisms and to determine the preimaginal conditioning effect on resistant genotypes using O. ilicis reared on C. canephora. Resistance by antixenosis was not found; however, nine genotypes showed resistance to O. ilicis via an antibiosis mechanism. Two of these resistant genotypes showed a more persistent resistance than the O. ilicis reared on C. canephora, which indicated that a previous host can affect the selection of a genotype by O. ilicis. The study may provide a model to evaluate the preimaginal conditioning effect on plant resistance, which can be useful for plant breeders. [ABSTRACT FROM AUTHOR]

The broad mitePolyphagotarsonemus latus(Banks) was studied for one season (2009/2010) on three pepper cultivars (Travita, Top star and Habeba) in the nethouses in Egypt. The tarsonemid mite was fed upon by the predatory phytoseiid miteAmblyseius swirskii(Athias–Henriot). Population abundance of the tarsonemid pepper prey was affected by climatic conditions and predation. A control measure of one preventive treatment in nursery and two successive curative treatments, applied mid-September, in nethouses seemed to be the most successful management of the harmful mite. The effect of constant different temperatures onP. latusdevelopment, reproduction and population growth was investigated. At 11 °C, all activity ceased and by 36 °C the adult began to slow down. Life table parameters varied greatly, especially at 21 °C and 75% R.H. [ABSTRACT FROM AUTHOR]

A new species of stigmaeid mite (Acari: Stigmaeidae)Agistemus paraguariensissp. nov.is described and illustrated from the State of Rio Grande do Sul, Brazil, based on specimens collected on yerba mate (Ilex paraguariensisA. St.-Hil.) (Aquifoliaceae). A key to Brazilian species of the genus is provided. urn:lsid:zoobank.org:pub:D92FFB81-BD07-414E-A7B0-DDAA6C71CE52 [ABSTRACT FROM PUBLISHER]

The stigmaeid mites collected from Guilan Province in Northern Iran were investigated. A new speciesCheylostigmaeus guilaniensissp. nov.is described and illustrated. The following five stigmaeid species are new records for the Iranian fauna:Eryngiopus bakeriGonzalez, 1965;Eustigmaeus ottavii(Berlese, 1910);Ledermuelleriopsis spinosaWood, 1967;Stigmaeus glypticusSummers, 1962; andStigmaeus petrophilusKuznetsov & Petrova, 1979. A tabulated checklist for stigmaeid species recorded from Iran is also provided. urn:lsid:zoobank.org:act:923C7C29-F2EC-46AE-B94C-64A9293C349C [ABSTRACT FROM PUBLISHER]

Field experiments were carried out with the goal of estimating the population fluctuations of the wheat curl mite,Aceria tulipaeKeifer, and its control. These experiments were conducted at an abandoned wheat field in Egypt during a growing season in 2012 in Cairo Governorate. Also, studies on life history aspects and reproductive parameters of the same species in the laboratory at 251 °C and 6015% R.H. were carried out. There were population fluctuations of the wheat curl mite,A. tulipae, when affected by temperature increase during the experimental season. The results showed that the population fluctuation continued at a moderate level until the end of February and then started to increase until it reached to three peaks from the mid of March to the mid of April when the temperature degrees were at 17–24 °C.A. tulipaeremoves cell contents of the leaves which generally become yellow. The obtained data indicated that the total developmental time of the immature stages was 8.90 ± 0. 74 and 9.58 ± 0.88 days for male and female, respectively, and the female fecundity was 22.8 eggs; 1.17 eggs/♀/day. Intrinsic rate of increase (rm) was found to be 0.153 individuals per female per day and the population multiplied 12.54 times in a generation time of 19.20 days under the given conditions. Three acaricides: Abamectin, Antimite and Sulphur were selected to control the wheat miteA. tulipae. The results of control pest experiments indicated that the Abamectin was superior in reducing the wheat miteA. tulipae(79% reduction) compared to Sulphur and Antimite which had approximately equal reductions (67 and 65% reductions, respectively). The study ended with the conclusion that the population of the wheat miteA. tulipaewas significantly highest at the interval from the mid of March to the mid of April. The wheat miteA. tulipaeis considered to be disastrous as its intrinsic rate of increase (rm) is high and the best control of this species at this interval was attained with Abamectin. [ABSTRACT FROM AUTHOR]

The morphometric comparison of two similar species fromSpinturnix myotigroup,S. myotiandSpinturnix andegavinabased on the records from Romania and Ukraine was undertaken. Discriminant characteristics for nymph stadium are provided. Morphometric features of adult stages of these two species are discussed with respect to their applicability for species determination. Description and key features of nymphal stages ofS. andegavinawere compiled using metric and non-metric body characteristics. Records ofS. andegavinafrom Romania and Ukraine are reported for the first time and previous records of spinturnicid mites fromMyotis daubentonii(Kuhl, 1817) in northern Europe and Asia are also discussed. [ABSTRACT FROM PUBLISHER]

Tenuipalpus shishehbourisp. nov., collected from pomegranate trees (Punica granatum, Lythraceae), is described from Darab, Fars Province, Iran. Six species are re-described:Tenuipalpus daneshvariKhosrowshahi and Arbabi,Tenuipalpus euonymiKhosrowshahi,Tenuipalpus granatiSayed,Tenuipalpus kamaliiKhosrowshahi and Arbabi,Tenuipalpus parsiiKhosrowshahi and Arbabi andTenuipalpus punicaePritchard and Baker. A key to all known Iranian species is provided. http://zoobank.org/urn:lsid:zoobank.org:pub:40C1657A-8ED8-4840-82B0-02427D54C967 [ABSTRACT FROM PUBLISHER]

Aceria tulipaeis one of the most damaging mite pests of garlic in the Gangetic Basin of West Bengal. The mite causes damage by infesting along the midrib of leaf. The leaves of infested plants are curled and twisted in a characteristic manner, and growth is stunted, causing 32% yield loss in this study under West Bengal conditions. The mite causes devastating damage to stored garlic also. Mite population initiated at the end of December and attained maximum numbers during mid-February. The garlic cultivar, Katki, was recorded as tolerant, whereas Goldana was susceptible to the mite attack. Ambient temperature and relative humidity were positively correlated with the mite population, whereas rainfall was correlated negatively. [ABSTRACT FROM PUBLISHER]

The tea red spider mite, Oligonychus coffeae Nietner (Tetranychidae), is considered one of the main phytophagous mite pests of tea plants in north-east India. To reduce the amount of synthetic chemicals in tea, a strategy of using optimal rates and effective spray practices has been developed. In laboratory tests, the 50% lethal concentration (LC50 in parts per million (ppm)) values of ethion, dicofol, profenofos, propargite, fenpropathrin, fenazaquin and abamectin were 687.18, 534.04, 241.684, 90.256, 12.549, 4.319 and 2.405, respectively. Field rates of these acaricides were compared with 95% lethal concentration (LC95 in ppm) values, and a decrease in the susceptibility of the test population to ethion, dicofol and profenofos was observed. There was no change for the newly introduced acaricides like fenazaquin, fenpropathrin, propargite and abamectin, which were effective at doses lower than the recommended dose. Of all the acaricides tested, abamectin was the most toxic and ethion was the least toxic. On the basis of LC50 values, the descending order of ovicidal toxicity of the acaricides tested to O. coffeae eggs was fenazaquin, followed by profenofos, propargite, fenpropathrin, ethion, dicofol and abamectin. The data obtained in this study may be used as a tool in integrated pest management strategies that can effectively control the pest. [ABSTRACT FROM AUTHOR]

The Bdella tropica is a predatory mite of potential importance in biological control of spider mites. Therefore, we conducted this experiment to understand its biology. The laboratory experiments showed that Bdella tropica Atyeo failed to develop at temperatures of 15 ± 1°C and 35 ± 1°C, but its development was normal at temperatures of 17 ± 1°C, 21 ± 1°C, 25 ± 1°C, 29 ± 1°C, and 33°C ± 1°C, although it could not oviposit at 17 ± 1°C. The results showed that the development of B. tropica was the longest (115.3 days) at 17 ± 1°C and shortest (37.4 days) at 33 ± 1°C, and shortened with increasing temperature within the range of 17–33°C. The survivorship of B. tropica increased with increasing temperature from 15 to 29°C and decreased with increasing temperature within the range from 29 to 35°C. The developmental threshold of temperature of the immature stage was 11.3°C, and the effective thermal summation of immature stage was 843.2 degree-days. The relationships between development and temperature were approximately linear within the range of 17–33°C. These results will help to evaluate the potential of B. tropica as a biological control agent against spider mites. [ABSTRACT FROM PUBLISHER]

Adactylidium gynaikothripsi n. sp. belonging to the family Acarophenacidae, found in Greece associated with Gynaikothrips ficorum (Marchal), is described and illustrated. A key of the world species of genus Adactylidium is given. The new species may have potential importance in the biological control of this thrip species. [ABSTRACT FROM PUBLISHER]

In this study the esterases involved in abamectin resistance have been characterized from the two-spotted spider mite, Tetranychus urticae Koch. The resistant strain of T. urticae showed ≥ 3000-fold resistance to abamectin compared with the susceptible strain. Enzyme assays revealed that esterase activity in the resistant strain was 2.14-fold and 1.33-fold higher than that of the susceptible strain when α-naphthyl acetate (α-NA) or α-naphthyl propionate (α-NP) was used as substrate, respectively. In contrast, there was no significant difference in the enzyme activity among the resistant and susceptible strains when β-naphthyl acetate (β-NA) or α-naphthyl butyrate (α-NB) were used as substrate. Km and Vmax values of the resistant strain to α-NA were 1.43 and 1.68 times lower and higher than that of susceptible strain, respectively. The results showed a significant difference in the esterase patterns and abamectin and rosemary essential oil showed a potent inhibitory effect on esterase in resistant and susceptible strains. The optimum temperature (30°C) and optimum pH (pH 6.5) for relative activity of esterase for both strains is the same. The effects of different concentrations of several reagents on the relative activity were also investigated. [ABSTRACT FROM AUTHOR]

Laboratory investigations on the biology of Tyrophagus putrescentiae (Schrank), a stored-food mite and the predator Neoseiulus pseudolongispinosus (Xin, Liang and Ke) were conducted using the flour of soybean (Glysin max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.) as hosts. Efficiency of food was estimated according to time required for immature development, female fecundity, and survival of both sexes. Results indicated that the breeding activity of predatory mites fed on T. putrescentiae that had been cultured on wheat flour was more viable than that when T. putrescentiae were fed on maize and soybean hosts. Egg, larval, protonymphal, and deutonymphal stages of T. putrescentiae that fed on T. aestivum had faster development compared to those fed on Z. mays and G. max. Fecundity of T. putrescentiae was higher (23.8) on T. aestivum, than on the other diets tested (17.1 eggs on Z. mays and 11.4 eggs on G. max); female longevity averaged 34.1, 27.0, and 40.8 days and male longevity was 23.5, 18.7, and 28.7 days when raised on Z. mays, G. max, and T. aestivum, respectively. On a diet of T. aestivum the mean generation time from egg to adult of T. putrescentiae lasted for 11.7 days compared to 15.2 and 18.8 days when fed on Z. mays and G. max, and net population growth was 119.0, 61.0, and 32.0 mites per g substrate, accordingly. The predatory mite N. pseudolongispinosus when fed on T. putrescentiae cultured on different diets could reproduce normally and completed its development as successfully as T. putrescentiae. Average duration of egg and nymph development of N. pseudolongisponosus was statistically fastest with T. aestivum-fed T. putrescentiae compared with Z. mays and G. max. Mean total longevities of the female (29.4, 25.8, and 17.7 days) and male (20.8, 16.8, and 13.1 days) were significantly longer on T. aestivum than on Z. mays and G. max, respectively. Mean daily fecundity of female adults also increased on T. aestivum (3.5 per day) but decreased (2.8 and 1.2 per day) with Z. mays and G. max, while, total developmental time was 10.1, 11.8, and 12.9 days, respectively. The assessment of macronutrients in soybean, maize, and wheat flours showed that wheat had more carbohydrate and ash but reduced protein and fat contents and merits as leading compound in supporting higher mite populations. Consequently, the mass production N. pseudolongispinosus as a potential biocontrol agent under field as well as storage conditions using T. putrescentiae reared on a wheat diet would be an appropriate strategy. [ABSTRACT FROM AUTHOR]

Sancassania polyphyllae (Acari: Acaridae) adult female mites will feed on insect cadavers and infective juveniles (IJs) of entomopathogenic nematodes. Our objective was to determine whether S. polyphyllae has a food preference when offered a choice between tissues of Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), or IJs of Steinernema feltiae (Rhabditida: Steinernematidae) or IJs of Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae). When offered a choice between no food and one of the different food sources, P. fullo, G. mellonella or S. feltiae IJs, S. polyphyllae had a significant preference for food sources compared to no food. When it was offered either no food or H. bacteriophora, there was no significant difference in the mite distribution. When offered two different food choices, P. fullo or G. mellonella, P. fullo or S. feltiae, and P. fullo or H. bacteriophora, the mite showed significant preferences for P. fullo larvae. In S. feltiae vs. G. mellonella and S. feltiae vs. H. bacteriophora experiments, S. polyphyllae showed significant a preference for S. feltiae. In three-choice experiments, S. polyphyllae had a preference for P. fullo, followed by S. feltiae, G. mellonella and H. bacteriophora, respectively. Our data confirm, in part, our hypothesis that when offered different food choices, this mite species prefers tissues of its phoretic host, P. fullo over lepidopteran host tissues or living IJs. Based on these laboratory data, H. bacteriophora should be used as a biological control agent against P. fullo over a Steinernema species. [ABSTRACT FROM AUTHOR]

Copper oxide (CuO) has broad-spectrum anti-microbial and anti-fungal properties. The aim of this study was to test the acaricidal efficacy of CuO-impregnated fabrics on the common house dust mite, Dermatophagoides farinae. The overall vitality/mobility of the mites was reduced when they were exposed to the CuO-impregnated fabrics and, when possible, the dust mites migrated to fabrics where no CuO was present. The mortality of mites exposed for 10 days to fabrics containing 0.2% (w/w) CuO was significantly higher than the mortality of mites on control fabrics (72 ± 4 and 18.9 ± 0.3%, respectively). The mortality reached 95.4 and 100% with fabrics containing 0.4 and 2% CuO after 47 and 5 days, respectively. The acaricidal effect of copper oxide seems to be due to direct toxicity. The use of fabrics containing copper oxide may thus be an important avenue for reducing house dust mite populations, and for reducing the load of dust mite allergens. [ABSTRACT FROM AUTHOR]

The adoption of pest and disease management practices has been the subject of numerous studies. Unfortunately, there is little consistency in their findings with regard to the variables that influence growers' decisions to adopt these techniques. In this study we focus on context as a means of explaining the lack of consistency. We used the results of in-depth interviews and a mail survey to explore context as a predictor of Australian apple growers' behaviour with respect to the management of codling moth and pest mites. We found that climate, topography, spatial separation between orchards and the crop mix determined the type and intensity of pest and disease pressures experienced by growers. Given the types and intensities of pest and disease pressures present, the management practices growers used depended on the range and effectiveness of the control options that were available to them. We concluded that variables representing specific aspects of orchard context were the primary determinants of the particular combinations of pest and disease management practices used by apple growers, not variables representing demographic and general enterprise characteristics that have been proposed in past studies. [ABSTRACT FROM AUTHOR]

Biological control using the mite-pathogenic fungus Hirsutella thompsonii is being investigated, targeting the economically important coconut mite (Aceria guerreronis) in Sri Lanka. Local surveys were carried out to assess background levels of H. thompsonii from coconut mite populations. Environmental profiling, based primarily in the laboratory, assessed the suitability of each isolate as a biological control agent. Coconut mites infected with H. thompsonii were found in each district we surveyed. Profiling indicated an optimum temperature for isolate growth of 25-30°C, with growth recorded at 35°C, for all isolates. Six hours of simulated tropical sunlight reduced spore viability, although viability still exceeded 84%. There were more pronounced losses in viability after 2 h of uninterrupted natural sunlight in a coconut plantation. However, there were indications that spore viability was being inhibited by a combined sunlight/temperature effect. There was no lethal effect on one of the coconut mite's predators, Neoseiulus baraki, when the latter was inoculated with one of the fungal isolates. [ABSTRACT FROM AUTHOR]

The hemp russet mite Aculops cannabicola (Farkas) is a little-known but potentially dreadful pest. It primarily feeds on leaves, petioles, and meristems. The mites quickly spread between plants grown in proximity. They cause a curling of leaf edges, followed by leaf russeting. The mites feed on the inflorescences of both sexes, and on glandular trichomes, severely reducing resin production. The hemp russet mite constitutes a real menace to world hemp cultivation, because it cannot be controlled easily. [ABSTRACT FROM PUBLISHER]

Two female Phytoseiulus persimilis and their offspring eliminated two-spotted spider mite Tetranychus urticae from hop leaf discs faster than two female Neoseiulus californicus and their offspring at 25 °C. A combination of one female of each species and their offspring eliminated spider mites faster than the N. californicus alone, but slower than P. persimilis alone. Air relative humidities of 55and 93ad no effect on predation. Both predator species cannibalised eggs and juveniles when spider mite numbers were low. In field experiments in 1996, fewer spider mites were recorded where P. persimilis was released, irrespective of the presence of N. californicus. Pest numbers on cv. 'First Gold' were lower than on cv. 'Herald'. No differences were recorded between the numbers of spider mite eggs in predator release treatments on 'First Gold', but fewer active stages of spider mites were recorded on plots with P. persimilis than controls soon after the time of peak pest population densities. On 'Herald', fewer spider mite active stages and eggs were recorded where predators were released than on untreated controls. [ABSTRACT FROM AUTHOR]

The article presents information on the threats caused by verroa mite to honey bees and research for honey bee varieties with tolerance for it. Verroa mite is a blood sucking parasite and are ranked as one of the worst enemies of honey bees worldwide. They have also developed tolerance for various chemicals. ARS entomologist Eric H. Erickson and colleagues have monitored mite infestations in research apiaries.

"The Diagnostic Challenge of Nonburrowing Mite Bites: Cheyletiella yasguri," E. Dorinda Shelley, et al. Endemic pruritus in a family of four proved to be caused by the "bite and run" habits of the Cheyletiella yasguri mites that lived on the family dog. The mystery was solved only after the 6-year-old daughter experienced an explosive attack of pruritic papules after taking a nap in the dog's sleeping box. Virtually invisible ectoparasites remain a common cause of endemic pruritus within families. Since these patients show no acarologic, clinical, or laboratory evidence for the cause of their itch, a good rule remains, cherchez le chien. (Journal of the American Medical Association 1984;251:2690–2691.) "The Clinical Utility of the Dexamethasone Suppression Test in Psychiatry: Summary of a National Institute of Mental Health Workshop," Robert M. A. Hirschfeld, et al. The dexamethasone suppression test (DST) is being increasingly used in psychiatry, especially in the differential diagnosis of affective disorders. In light of this, the National Institute of Mental Health convened a workshop of clinical scientists drawn from neuroendocrinology, psychopathology, and general clinical psychiatry to review the evidence for the efficacy of the use of the DST in psychiatry. Specifically considered were DST's relevance to differential diagnosis, its use as a predictor of response to treatment, its relationship with other biologic variables, and technical issues. The panelists concluded that at this time there are no clear indications for routine use of the DST in diagnosis or clinical management of depression, although it is a useful research tool. Areas of potential utility include prediction of suicidal activity, prediction of relapse, and differential diagnosis. (Journal of the American Medical Association 1983;250:2172–2174.) [ABSTRACT FROM AUTHOR]