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Tomato crops are attacked by several pests, including mites. While the main predatory mites are not effective enough to control mite pests, recent studies have shown encouraging results with the European endemic phytoseiid Typhlodromus (Anthoseius) recki. The first objective of the study was to assess the ability of this species to disperse along the tomato stem, considering six genotypes of Solanum lycopersicum, S. peruvianum and S. cheesmaniae with contrasted trichome numbers and types of stem trichomes, accuratetly characterised in a previous study. The second objective was to determine how predator morphological traits can explain dispersal along the tomato stem. For this, ambulatory dispersal ability of females (stem crossing rate success, hesitation and escape behavior, mobility periods) was tested in lab conditions on the eight Solanum genotypes, at four period of time after the predator introduction (10, 25, 55 and 100 min), with a video observation of 5 min at each period. The females were then mounted on slides and body length and width (at the fore hind, middle and back parts) measured. No effect of the tomato genotypes was observed on the dispersal ability of the predator. However, specimens that succeeded in crossing the stem, had a higher percentage of mobility time (79.36%) than those that failed (43.60%). Furthermore, body width at midbody (DSW2) and dorsal shield length (DSL) were negatively correlated with dispersal ability. The mean DSL and DSW2 of the females that succeed to cross were 342.3 and 160.9 μm, respectively vs. 345.6 and 164.9 μm, for females that did not succeed. This suggests that the more slender and relatively small the specimens, the more are mobile and able to successfully cross the stem. The number of glandular trichomes type (GT) VI and to a lesser extent GT I and IV, and non-glandular trichomes (NGT) II&III appear to limit dispersal. The GT VI seems to have a repellent effect. On the opposite, the number of NGT V were positively correlated with high mobility and stem crossing rates. Assuming that the main barrier to biological control efficiency is dispersal along tomato stems, these preliminary results should have implications for biological control success. The proportion of mites with 'optimal dimensions' appears to be low and further studies should be undertaken to better assess the proportion of mites with such ideal dimensions in different populations and also to determine whether these morphological traits are associated with different feeding abilities and/or abiotic conditions. [ABSTRACT FROM AUTHOR]

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

Cyclamen mite is a nearly global pest of strawberry, inhabiting concealed spaces within folded leaves and flower buds emerging from plant crowns. It feeds on new plant tissue causing leaf discoloration and deformation, stunted plants, fruit bronzing and cracking, and yield losses at high population levels. Because ultraviolet-C (UV-C) irradiation is a promising new tool for disease and pest management in strawberry, and because there are few control options for cyclamen mite, we tested the direct, short-term effects of UV-C on cyclamen mite populations in potted strawberry plants in a controlled environment. Results from three experiments showed few differences in cyclamen mite populations on controls versus plants treated with UV-C (0.237 W m−1) for 3 or 4 weeks. In the second experiment, using a different strawberry cultivar and directing the UV-C from above the plant crown only, there was indication of a mild effect that may be due to some direct mortality and/or indirectly to plant defenses. However, longer-term studies will need to be conducted to determine whether pre-infestation exposure to UV-C can enable strawberry plants to better resist or tolerate cyclamen mite populations. Direct mortality did not occur as in previous experiments with pests, like twospotted spider mite, that live primarily on opened leaves. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arab Journal of Plant Protection is the property of Arab Society for Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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

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

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

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

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

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

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

Simple Summary: The organosilicone is commonly used as surfactant ingredient in agriculture. Some pilot studies showed pesticidal activities of some organosilicone surfactants. This study examined the toxicity of an organosilicone, Silwet 408, to the two-spotted spider mite Tetranychusurticae and explored the field usage of this chemical in pest control. We tested this chemical on eggs, nymphs, and adults of T. urticae. We applied a two-sprays strategy to enhance the field control efficacy based on the high toxicity of Silwet 408 to nymphs and adults and the lack of toxicity to eggs of T. urticae. However, their phytotoxicity should be taken under consideration. Our study improved our understand of the toxicity and safety of organosilicone surfactants. The results provide a basis for the usage of this chemical in mite control. Organosilicone molecules represent important components of surfactants added to pesticides to improve pest control efficiency, but these molecules also have pesticidal properties in their own right. Here, we examined toxicity and control efficacy of Silwet 408, a trisiloxane ethoxylate-based surfactant, to the two-spotted spider mite (TSSM), Tetranychus urticae and its crop hosts. Silwet 408 was toxic to nymphs and adults of TSSM but did not affect eggs. Field trials showed that the control efficacy of 1000 mg/L Silwet 408 aqueous solution reached 96% one day after spraying but declined to 54% 14 days after spraying, comparable to 100 mg/L cyetpyrafen, a novel acaricide. A second spraying of 1000 mg/L Silwet 408 maintained control efficacy at 97% when measured 14 days after spraying. However, Silwet 408 was phytotoxic to eggplant, kidney bean, cucumber, and strawberry plants, although phytotoxicity to strawberry plants was relatively low and declined further seven days after application. Our study showed that while the organosilicone surfactant Silwet 408 could be used to control the TSSM, its phytotoxicity to crops should be considered. [ABSTRACT FROM AUTHOR]

The ham mite, Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), is a common pest infesting several stored products, particularly the aged hams. In this study, we reported the efficacy of nitric oxide (NO) fumigation, a recently discovered fumigation treatment under the ultra-low oxygen environment, at various concentrations and time under the laboratory conditions at 25°C against different mite stages on both dietary media and ham meat. Our results showed that NO fumigation was effective against all mite stages and 100% control was achieved. Generally, the egg was the most tolerant stage and required 48-, 24-, 16-, and 8-h treatments to achieve 100% mortality at 0.5, 1, 1.5, and 2% NO concentration on dietary media, respectively. Tyrophagus putrescentiae mobile immatures and adult stages were less tolerant, and 100% mortality was achieved after 16-, 8-, 8-, and 4-h treatment at 0.5, 1, 1.5, and 2% NO, respectively. The median lethal concentration (LC50) of NO on egg was 0.86, 0.68, and 0.32% for 8-, 16-, and 24-h treatments. In addition, a confirmatory test was conducted on ham meat at 0.5 and 1.0% of NO and similar efficacy was found. Complete control of egg was achieved after 48- and 24-h treatment at 0.5 and 1.0% of NO, respectively, and larvae and adult mites were 100% controlled after 16 and 8 h at 0.5 and 1.0% of NO, respectively. Our results demonstrated that NO fumigation was effective against T. putrescentiae and can be a potential alternative treatment to methyl bromide for cured-ham pest control. [ABSTRACT FROM AUTHOR]

Phytophagous mites can cause economic losses in many crops, including grapevines. The changes in their population levels may be associated with changes in the predator-prey relationship. Knowledge of the distribution of mites in plants is important for planning sampling strategies and facilitating control decisions. The aims of this study were to (i) evaluate the abundances of Tetranychus urticae (Tetranychidae) and Neoseiulus californicus (Phytoseiidae), and the correlations between them and environmental factors; (ii) determine their distribution on the top, middle, or base strata of the evaluated grapevines (Vitis vinifera, Chardonnay cultivar) and, additionally, report the first occurrence of damage caused by T. urticae in grapevine leaves in the state of Rio Grande do Sul, Southern Brazil. Sixteen samplings were conducted, divided between the 2018 and 2019 seasons. In each sampling, three leaves from the three strata of the plant (top, middle, and base) were collected from 20 plants, totaling 60 leaves per sampling. The predator-prey relationship and their association with environmental variables were evaluated with multivariate correlation, whereas the number of mites per plant leaf strata was compared using a generalized linear mixed model in R software. It was possible to observe the symptoms of damage caused by T. urticae attacks on grapevines in Southern Brazil, characterized by the presence of yellow spots and general yellowing of the vineyard. Our findings indicate that T. urticae and N. californicus individuals are strongly associated with each other regardless of the environmental variables, and such relationship occurs mainly on the lower strata (middle and base leaves) of grapevines. Thus, by taking into account the damage on the leaves of grapevines and the occurrence of T. urticae and N. californicus majorities on specific strata of these vineyards, we suggest that the lower strata of grapevines should be the priority targets for management strategies to control such mites. [ABSTRACT FROM AUTHOR]

The broad mite Polyphagotarsonemus latus (Banks) is a polyphagous pest with a cosmopolitan distribution. The combined application of botanical pesticides and entomo-acaropathogenic fungi may serve as an eco-friendly approach in controlling the mite. In this study, the Mimosa pudica (Fabales: Fabaceae) leaf aqueous extract (MpAE) was initially tested to determine its effects on the mycelial growth, sporulation, and conidia viability of the entomo-acaropathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae). The compatibility was then determined based on the biological index (BI) value. The bioefficacy of MpAE and B. bassiana at various concentrations was evaluated against P. latus, both alone and in combinations. Each treatment was sprayed into an arena containing a citrus leaf disc and gravid females of P. latus. The mortality and oviposition rate of the females were observed until 120 h after application. The results showed no reduction in B. bassiana mycelial growth, sporulation, and conidia viability when MpAE was incorporated into the culture medium. The BI value ranged from 100.01 to 136.30, indicating that MpAE was highly compatible with B. bassiana. The individual and combined applications of MpAE and B. bassiana significantly increased the mite mortality and simultaneously inhibited the mite oviposition rate. The mite mortality varied from 90 to 100% at 120 h after application in the treatment groups. The mite oviposition rate was significantly decreased, ranging from 11.50 to 29.00 eggs in the treatment groups, while it was 57.25 eggs in control. Therefore, the application of MpAE and B. bassiana propose a valuable alternative to integrate into pest management programs. [ABSTRACT FROM AUTHOR]

BACKGROUND The tomato russet mite (TRM), Aculops lycopersici, and powdery mildew (PM), Oidium neolycopersici, are two major problems in tomato cultivation for which no effective biocontrol solutions exist to date. In a greenhouse compartment, we investigated the potential of preventatively establishing the iolinid omnivorous mite Pronematus ubiquitus on potted tomato plants to control both pest and pathogen simultaneously. RESULTS: Using Typha pollen, P. ubiquitus established well on tomato plants, with numbers reaching up to 250 motiles per tomato leaflet. The built‐up population was capable of controlling subsequent infestations with both TRM and PM. This represents the first report of an arthropod protecting a crop against pests as well as disease. CONCLUSION: The implementation of P. ubiquitus in tomato crops could be a real game‐changer as it eliminates the need for repeated pesticide use or sulphur applications. The finding that arthropods can effectively control diseases opens up new opportunities for biological crop protection. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Predatory mites represent important biological control agents and those belonging to the Phytoseiidae family are the most promising for the control of phytophagous mites and small insects. The control of key pests of tomato and other solanaceous crops, highlighting phytophagous mites, has been a challenge and the biological control constitutes a promising strategy. Prospecting predatory mites in wild host plants, natural environments as well as in agroecosystems is relevant because these non-crop and crop areas can serve as reservoirs for promising species for biological control programs. This study aimed to know the Phytoseiidae fauna associated with wild and cultivated solanaceous plants in a poorly prospected area in Brazil, the Central-West Region. A detailed taxonomic identification of phytoseiid mites was conducted, and the most important morphological traits are presented for each species. In addition, associated phytophagous mites mainly belonging to the Tetranychidae, Tenuipalpidae and Eriophyoidea were identified. Surveys were carried out in 23 species of solanaceous collected in the Distrito Federal (12 areas) and Goiás State (1 area), from February 2017 to January 2018. Nineteen species of predators belonging to ten genera were recorded: Amblyseius (2 species), Euseius (3), Galendromus (1), Iphiseiodes (1), Neoseiulus (3), Paraphytoseius (1), Phytoseius (3), Proprioseiopsis (2), Typhlodromalus (2, one probably new to science) and Typhlodromips (1). Solanum lycocarpum was the solanaceous that harbored the highest richness (11 species), as well as the one with the highest abundance of phytoseiids (250 specimens). Typhlodromalus aripo was the most common species, being the most abundant (423 specimens; 32%) and registered on the largest number of hosts (14). Many of phytoseiid species found present morphological traits that facilitate their occurrence in leaves with trichomes, as in the case of tomato and other cultivated solanaceous. These traits and the association between predators and phytophagous mites may indicate that these species are promising for biological control programms. Thus, extensive studies to assess the efficiency of the identified predatory mites to control key solanaceous pests are required. [ABSTRACT FROM AUTHOR]

Predatory mites, comprising of members Phytoseiidae, Cheyletidae, Cunaxidae, Stigmaeidae, Bdellidae, Tydeidae, Anystidae and Erythraeidae are those which feed on phytophagous mites and small insects. Among the entire predatory mites group, Phytoseiidae are the most important one because of their potential ability in controlling mite pests and small squashy-bodied insect pests. Phytoseiids are one of the most investigated and squeezed group of all predatory mites. In a farming nation like India, predatory mites merit extraordinary notice where agriculture, being the prime livelihood is consistently under the danger of pestilence. Many species of phytoseiids are mass cultured and released on the field as a bio-control agent, among which Neoseiulus longispinosus (Evans) holds an important position due to its immense potential of predation and so this article reviews available data on the biology, predation and mass rearing of this important Phytoseiid mite species. [ABSTRACT FROM AUTHOR]

Formic acid (FA) has been used for decades to control Varroa destructor, one of the most important parasites of the western honey bee, Apis mellifera. The rather unselective molecular mode of action of FA and its possible effects on honeybees have long been a concern of beekeepers, as it has undesirable side effects that affect the health of bee colonies. This study focuses on short-term transcriptomic changes as analysed by RNAseq in both larval and adult honey bees and in mites after FA treatment under applied conditions. Our study aims to identify those genes in honey bees and varroa mites differentially expressed upon a typical FA hive exposure scenario. Five detoxification-related genes were identified with significantly enhanced and one gene with significantly decreased expression under FA exposure. Regulated genes in our test setting included members of various cytochrome P450 subfamilies, a flavin-dependent monooxygenase and a cytosolic 10-formyltetrahydrofolate dehydrogenase (FDH), known to be involved in formate metabolism in mammals. We were able to detect differences in the regulation of detoxification-associated genes between mites and honey bees as well as between the two different developmental stages of the honey bee. Additionally, we detected repressed regulation of Varroa genes involved in cellular respiration, suggesting mitochondrial dysfunction and supporting the current view on the mode of action of FA—inhibition of oxidative phosphorylation. This study shows distinct cellular effects induced by FA on the global transcriptome of both host and parasite in comparison. Our expression data might help to identify possible differences in the affected metabolic pathways and thus make a first contribution to elucidate the mode of detoxification of FA. [ABSTRACT FROM AUTHOR]

Experiment was laid out in RBD design with seven treatments comprised of pruning of affected twigs (July & October) and miticides (chlorfenapyr & spiromesifen) sprayed twice in July and once in October months to evaluate the efficacy of various integrated approaches. Results revealed that initial mite infestation ranged from 31.9 to 45.9%. During 2017-18, no mite infestation was recorded from October to fruiting stage in pruning and removal of affected twigs followed by two spraying of chlorfenapyr 10 EC (0.03%) or spiromesifen 22.9 SC (0.034%) at 15 days interval during July and again pruning in October with one spraying of chlorfenapyr or spiromesifen against 89.0% in control at fruiting stage, followed by no pruning in October along with spraying of chlorfenapyr with 7.6% mite infestation at flowering stage. Similar trend in 2018-19 confirmed that pruning in July and October followed spraying of miticides (chlorfenapyr or spiromesifen) twice in July and once in October were highly effective against litchi mite. [ABSTRACT FROM AUTHOR]

Objective To compare a commercial pest control program vs a biological pest control program in cucumber (Cucumis sativus var. Jawell) cultivation, evaluating quality and production standards. Design/methodology/approach The study was carried out in high-tech glass greenhouses, under a cooling system with damp walls and extractors, heating by irradiation, and automated irrigation. Two treatments were evaluated biological pest control in area A and a commercial control program in area B, both in Persian cucumber (Cucumis sativus) of the Jawell variety; each area of 160 m², separately, and 41,600 plants for each area. For biological control, the mite (Amblyseius swirskii) was released for the control of thrips; the wasp (Aphidius colemani) was released for aphid control; the mites (Phytoseiulus persimilis) and (Amblyseius californicus) for red spider control and application of the entomopathogenic nematode (Steinernema fetiae). The chemical control was in accordance with COFEPRIS (2019). The variables were fruit quality total production and incidence of pests in a completely randomized experimental design, and the t-student statistical test and Mann-Whitney test were done for the variables weight quality and loss (P≥0.05). A correlation was made between the incidence of thrips (Thrips tabaci) and the incidence of biological control. Results The biological control method was just as efficient as the chemical control method, in variables such as fruit weight, number of boxes obtained of quality cucumber, and incidence of pests and their biological control. Study limitations/implications It is important to perform more studies under field conditions where biotic and abiotic factors are different and in other regions, in addition to testing other registered biological products. Findings/conclusions Biological and chemical control are complementary, an integrated control would help to slowly adapt a company for a subsequent application of biological control, easing regularization and certification procedures that involve the use of chemicals. A more continuous release of A. swirskii is proposed and distributed during the cultivation weeks. [ABSTRACT FROM AUTHOR]

Tetranychus urticae Koch is one of the major pests that cause economic losses in pepper production. In the production of pepper, it is fed on the plant and causes loss of yield and quality in the plant. Within the scope of the integrated pest management, Acari family Phytoseiidae members are generally used for the control of these pests. Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) are most commonly used to control of mites in greenhouses. P. persimilis is most preferred because it is a specific predator and feeds only on Tetranychus species. In this study, the use and efficacy of bifenazate (Bif) and Phytoseiulus persimilis (PP) in the control of Tetranychus urticae on pepper in greenhouse conditions were determined. For this purpose, four-character experiment including Bif, PP, Bif + PP and control was established according to completely randomized design in the greenhouse. Evaluations were performed on the 1st, 3rd, 5th, 7th, 14th, 21st and 28th days after applying Bif and PP to determine mite density. According to the 28th day evaluation in 2017 and 2018, the number of hd (moving stage) / leaves was 0.53 and 0.53 hd / leaf for PP; 3.47 and 3.60 hd / leaf for Bif; 0.13 and 0.67 hd / leaf for Bif+ PP and 6.16 and 6.47 hd / leaf for control respectively. When the applications were evaluated in general, it was determined that the best control of T. urticae during both years was provided by Bif+ PP application. [ABSTRACT FROM AUTHOR]

Frankliniella occidentalis (Pergande) is an economically important pest worldwide and has demonstrated a particularly difficult to manage. Controlling soil-pupating thrips is a promising strategy for controlling F. occidentalis. Beauveria bassiana granules and soil inhabiting predatory mite Stratiolaelaps scimitus have been proposed as alternative control agents. This study evaluated the effect of the B. bassiana conidia on the survival, immature development, longevity, reproduction of S. scimitus by laboratory bioassays. The effect of B. bassianaused as granules on survival of S. scimitus was also assessed under potted condition. When B. bassiana was sprayed directly on each immature stage of S. scimitus at a concentration of 1×107 ml-1 conidia, their survival rates and developmental times were not affected. Direct spray of B. bassiana on female S. scimitus did not affect their reproduction and longevity. The potted test showed that B. bassiana used as granules has no impact on the density of S. scimitus. Our study suggested that using B. bassiana granules is compatible with release of S. scimitus in soil, and their combined use may be an alternative to traditional F. occidentalis management. [ABSTRACT FROM AUTHOR]

At least two parasitic mites have moved from Asian species of honeybees to infest Apis mellifera. Of these two, Varroa destructor is more widespread globally while Tropilaelaps mercedesae has remained largely in Asia. Tropilaelaps mites are most problematic when A. mellifera is managed outside its native range in contact with Asian species of Apis. In areas where this occurs, beekeepers of A. mellifera treat aggressively for Tropilaelaps and Varroa is either outcompeted or is controlled as a result of the aggressive treatment regime used against Tropilaelaps. Many mite control products used worldwide may in fact control both mites but environmental conditions differ globally and thus a control product that works well in one area may be less or ineffective in other areas. This is especially true of volatile compounds. In the current research we tested several commercial products known to control Varroa and powdered sulfur for efficacy against Tropilaelaps. Additionally, we tested the cultural control method of making a hive division to reduce Tropilaelaps growth in both the parent and offspring colony. Making a split or nucleus colony significantly reduced mite population in both the parent and nucleus colony when compared to un-manipulated control colonies. The formic acid product, Mite-Away Quick Strips®, was the only commercial product that significantly reduced mite population 8 weeks after initiation of treatment without side effects. Sulfur also reduced mite populations but both sulfur and Hopguard® significantly impacted colony growth by reducing adult bee populations. Apivar® (amitraz) strips had no effect on mite or adult bee populations under the conditions tested. [ABSTRACT FROM AUTHOR]

Greenhouse and field experiments were conducted to evaluate the effectiveness of site-specific tactics for management of the twospotted spider mite, Tetranychus urticae Koch, a major pest of greenhouse and field-grown strawberries ( Fragaria x ananassa Duchesne). Two site-specific (spot) treatments, the miticide bifenazate (Acramite) and the predatory mite Neoseiulus californicus McGregor, were compared with whole-plot treatments of bifenazate or N. californicus to determine whether T. urticae could be effectively managed in field-grown strawberry using only site-specific tactics. Additionally, the cost of site-specific tactics was compared with whole-plot treatments to determine the economic value of using site-specific management tactics for T. urticae in strawberries. In the greenhouse, all treatments equivalently reduced the number of T. urticae below control. In the field during the 2011-2012 season, more T. urticae eggs and motiles were in the whole-plot treatments of both N. californicus and bifenazate in the mid-season and late season, respectively, compared with the spot treatments. With the exception of site-specific N. californicus during the 2011-2012 field season, there were no differences in marketable yields between plots with site-specific treatments and whole-plot management. An economic analysis demonstrated a significant cost savings (75.3 %) with site-specific treatments of N. californicus compared with whole-plot application of N. californicus. Similarly, a 24.7 % reduction in cost was achieved in using site-specific bifenazate compared with whole-plot application of bifenazate. The findings indicate that site-specific treatments with N. californicus and bifenazate are competitive alternatives to whole-field application for T. urticae management in strawberries. [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]

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]

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]

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 basidiomycete Exobasidium maculosum causes Exobasidium leaf and fruit spot, an early-season disease of blueberry in the southern United States. Previous research suggested that the pathogen oversummers and overwinters epiphytically on the surface of blueberry bark and buds, most likely in its yeast stage. This is supported by the finding that a single dormant application of lime sulfur provides substantial control of the disease the following spring. As a surface resident for much of the year, E. maculosum is thus exposed to various horticultural and pest management practices which may affect its epiphytic population dynamics and impact subsequent disease development. The magnitude and consistency of such non-target effects was evaluated in multi-year field trials on susceptible 'Premier' and 'Tifblue' rabbiteye blueberry in southern Georgia. One fall application of stylet oil (timed to mimic sprays for blueberry bud mite control) or two fall applications of captan (timed to coincide with the management window for fungal foliar diseases) did not suppress Exobasidium leaf and fruit spot the following spring, whereas two fall applications of lime sulfur reduced the disease significantly (by 74.3% on average), albeit not to the same level as the late dormant lime sulfur standard (close to 90% average reduction across leaf and fruit spot intensity). A single late dormant spray of the growth regulator hydrogen cyanamide (a caustic compound with antimicrobial activity) suppressed disease intensity in most trials, but disease reduction was only partial (averaging 56.2% for leaf lesion density and 39.3% for fruit spot incidence). In contrast, a late dormant application of dormant oil consistently increased both leaf lesion density (by 80.7% on average) and fruit disease incidence (by 78.6%). The pronounced non-target effects associated with these off-season applications could explain variations in Exobasidium leaf and fruit spot risk among blueberry sites and years. • The basidiomycete Exobasidium maculosum, causal agent of Exobasidium leaf and fruit spot of blueberry, is thought to oversummer and overwinter eoiphytically in its yeast stage on blueberry plants in the field. • Applications of surface-active compounds (horticultural oils, hydrogen cyanamide, lime sulfur) during the fall and dormant season were evaluated for potential non-target effects on leaf and fruit spot development the following spring. • Fall sprays of lime sulfur and late dormant application of hydrogen cyanamide reduced disease levels, although less than the current standard for Exobasidium leaf and fruit spot control, a late dormant spray of lime sulfur. • The application of dormant oil increased subsequent disease levels considerably and significantly. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important pests in agriculture. Due to its short life cycle and high reproductive rate, this pest has become resistant to most acaricides. Therefore, finding alternative control strategies for this damaging pest is necessary. Application of microbiological agents with minimum concentrations of acaricides is a very suitable tactic in integrated pest management. In the present study, lethal effects of a chemical acaricide - spirodiclofen, and an Iranian strain of the entomopathogenic fungus Beauveria bassiana, were evaluated on different life stages of the two-spotted spider mite on two host plants, bean and cucumber. In the next step, compatibility of acaricide with the fungus was studied regarding conidial germination and vegetative growth of the fungus in the presence of different concentrations of the acaricide. Finally, the acaricide at rates of LC with the fungus at LC were sprayed on adult female mites. The results showed that immature stages of T. urticae were more susceptible to the acaricide whereas the adults were more susceptible to the fungus. Also, mites reared on cucumber were significantly more susceptible to the acaricide and fungus than those reared on bean. Spirodiclofen and the fungus had a synergistic effect; percentage of mortality for fungus infection was 48.6% and 53.5% on bean and cucumber, respectively, while it was 80.6% on bean and 84.5% on cucumber when the mite was sprayed with both the fungus and the acaricide. [ABSTRACT FROM AUTHOR]

Abstract: The ectoparasitic mite Varroa destructor is a major honey bee pest, and its control using pathogen-based biopesticides would resolve many of the problems, such as contamination and pesticide resistance, experienced with chemical control. A biopesticide, formulated with commercially-prepared conidia of a strain of Beauveria bassiana isolated from V. destructor was tested against the mites in bee colonies in southern France. The impact of treatment on hive survivorship, weight and mite infestation levels were very different from those of previous experiments using laboratory-prepared conidia: bee hives treated with the biopesticide died at a higher rate, lost more weight, and had higher mite densities at the end of the study than control hives. The biopesticide was subsequently found to be contaminated with bacteria. Two strains of bacteria were identified, by biotyping and sequencing data of the 16S rRNA and rpoB regions, and while the strains were distinct both were Pseudomonas sp. belonging to the P. fluorescens group. In dual cultures B. bassiana growth was slowed or suppressed when bacterial cfu density was about equal or greater than that of B. bassiana. Experiments using caged adult bees showed that bees ingesting diet and sugar solution treated with B. bassiana and kept at 30°C had significantly lower survival times than those treated with one of the bacterial strains, but the opposite was true at 33°C. Because one arthropod (honey bees) was treated for infestation by another (V. destructor), the impact of bacterial contamination was likely more noticeable than in most uses of biopesticides, such as treating plants against phytophagous insects. To reduce such risk in biopesticide development, a systematic screening for bacterial contamination prior to field application is recommended. [Copyright &y& Elsevier]

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]

A metabolite of the fungus Meira argovae Boekhout, Scorzetti, Gerson & Sztejnberg (Exobasidiomycetidae) was assayed as an antagonist of mites. Separation of extracted fungal metabolites by reversed phase liquid chromatography (RPLC), with subsequent testing of the obtained fractions, allowed us to isolate a single mite-antagonistic fraction (also active against a bacterium) that primarily includes one major component. This active compound (herein termed 'argovin') was identified by analyzing its spectral characteristics as 4,5-dihydroxyindan-1-one, which has previously only been described as a product of chemical reactions. The growth rate of the fungus was higher at a neutral pH than at an acidic one. Meira argovae adjusts the pH of its media to values optimal for its colony growth and toxic secretions. RPLC-cleaned argovin at 0.2 mg ml−1 killed 100% of a population of the citrus rust mite, Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae). This trait may be used to control citrus rust mites in the field, as well as for toxin production for industrial and pharmaceutical uses. [ABSTRACT FROM AUTHOR]

Abstract: The coconut mite Aceria guerreronis Keifer resides beneath the perianth of coconut fruits where it feeds on the tender meristematic tissue. A. guerreronis is one of the most important coconut pests but knowledge of its population dynamics is scant. We quantified seasonal and fruit age-related population fluctuations of A. guerreronis and its predator Neoseiulus paspalivorus DeLeon in Benin. N. paspalivorus was the most common and abundant beneath the bracts compared with other predators, which were very scarce and were largely found outside the bracts. Both percent fruit occupation and abundance of A. guerreronis and N. paspalivorus varied across sampling months as well as among coconut plantations and fruit age classes. Both parameters peaked in the middle of the rainy season and at the end of the dry season. Fruit age at which A. guerreronis and N. paspalivorus started to colonize the fruits was 0.9 and 1.2months, respectively. The two species reached their peak abundance (1512 A. guerreronis and 2.3 N. paspalivorus per fruit) on 3months-old fruits. Peak percent fruit occupation by A. guerreronis (∼70%) occurred after 4.3months, which was ∼0.7months earlier than that by N. paspalivorus (∼22%). Difficulties encountered by the predators in accessing the area beneath the perianth on the very young fruits allowed A. guerreronis a head-start in population build-up leading to strongly diverging population curves as a function of fruit age (higher population increase compared to N. paspalivorus). Protecting the very young fruits from A. guerreronis colonization should be a key issue for developing successful control strategies of this pest. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the resistance citrus red mite Panonychus citri which are considered to be the most important pesticide-resistant pests in China. The study collected six populations of the mite from Chinese citrus orchards to monitor their resistance to spirodiclofen and other five acaricides. Conclusion shows that there are essential difference in resistance to the evaluated acaricides among the examined populations of mite.

Pest management of insects and mites on orchids has been based on the use of synthetic organic pesticides. However, less-toxic chemical control is needed by hobbyists and small growers. Orchids from 8 genera were treated with Silwet L-77 alone and no evidence of phytotoxicity was seen. Subsequently, 3 petroleum oils in combination with Silwet L-77 were tested to determine efficacy in suppressing Boisduval scale Diaspis boisduvalii Signoret (Hemiptera: Diaspididae) and the flat mite Tenuipalpus pacificus Baker (Arachnida: Acari: Tenuipalpidae). The results indicate Silwet L-77 increased toxicity of the oils and increased removal of the scales and mites from foliage over oil alone, yet no phytotoxicity was observed in any of the plants treated. Petroleum oil + Silwet L-77 is considered low-toxic, may be less expensive than some pesticides, and may conserve natural enemies, making it a potential addition to an integrated pest management program for orchids. [ABSTRACT FROM AUTHOR]

Abstract: Control of invertebrate pests in broad-acre agriculture largely relies on the application of broad-spectrum pesticides, however resistance problems and environmental concerns are driving a search for alternatives including more selective products. Here we explore the feasibility of using novel chemical groupings in the control of problematic pests that attack germinating pastures and grain crops in Australia. A modified laboratory bioassay is described for testing the response of several invertebrate pests to pesticides that have contact and systemic/translaminar properties. Two contact pesticides (fenitrothion and gamma-cyhalothrin) and three pesticides with strong systemic/translaminar properties (lambda-cyhalothrin, abamectin and diafenthiuron) showed promise for control of the collembolan Sminthurus viridis and four mite pests (Halotydeus destructor, Balaustium medicagoense, Penthaleus falcatus and Bryobia sp.). No single pesticide emerged as the most efficacious against all these pests, highlighting the need for correct pest identification before making control recommendations. Incorporating these new chemical options into pest control programs may help to control emerging pests and counter pesticide resistance issues. Selective pesticides in particular are likely to be compatible with integrated control programs that promote the establishment and maintenance of beneficial natural enemies. [Copyright &y& Elsevier]

Abstract: The two-spotted spider mite, Tetranychus urticae was exposed to UV-C (250nm), UV-B (300nm), and UV-A (350nm). In non-diapausing females, the median effective doses for 50% mortality plus escape incidence (ED50) were 21 (UV-C) and 104kJm−2 (UV-B); those for 50% oviposition rate in continuous darkness-treated mites were 6.2 (UV-C) and 41kJm−2 (UV-B). No significant effects of UV-A on mortality and oviposition rate were observed. The ED50 values for UV-B were similar to the natural UV-B observed for 2–5 days in summer when T. urticae inhabits the undersides of leaves. Therefore, T. urticae possibly uses leaves as a filter to avoid the deleterious effects of UV-B. In diapausing females, low mortality was observed even at high doses of UV radiation, but more than half escaped even at low doses. The orange body color of diapausing females results from accumulation of carotenoids, a scavenger for UV-induced reactive oxygen species; this may explain the low mortality of diapausing females. Diapausing females may overcome the deleterious effects of UV-B during winter in the absence of leaves by emigrating to UV-free environments and by accumulating carotenoids. [Copyright &y& Elsevier]

Abstract: A bacterium, isolated from activated sludge and named strain TRP, could biodegrade chlorpyrifos and 3,5,6-trichloro-2-pyridinol. Phenotypic features, physiological and chemotaxonomic characteristics, and phylogenetic analysis of 16S rRNA sequence revealed that the isolate belongs to the genus of Paracoccus. Strain TRP could also degrade pyridine, methyl parathion and carbonfuran when provided as sole carbon and energy sources. Native-PAGE and enzymatic degradation assay of the cell-free extracts indicated that an alternative degradation mechanism might involve an inducible enzyme. Degradation study of chlorpyrifos by strain TRP was examined by GC–MS and HPLC; no persistent accumulated metabolite was observed. To the best of our knowledge, this is the first report of a bacterium that could completely mineralize chlorpyrifos. This isolate will be potentially useful in biotreatment of wastewaters and bioremediation of contaminated soils. [Copyright &y& Elsevier]

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]

The article discusses the resistance of pyrethroid on a major agricultural pest called Halotydeus destructor Tucker found in southern Australia. The Halotydeus destructor Tucker which is a redlegged earth mite is reported to be an essential pest of pastures and field crops. The author said that chemicals and few alternatives currently available is relied heavily in the control of this pest which also responses on pesticides. Toxicology bioassays were conducted on adult mites and results show for the first time that the species possesses high levels of resistance to two synthetic pyrethroids bifenthrin and alpha-cypermethrin. The need for more judicious management decisions to control pest species in a continuous manner is also reported.