Experimental and Applied Acarology最新文献

Brevipalpus mites pose a significant threat to citrus and coffee production worldwide due to their transmission of plant viruses. This study surveyed all seven provinces of Costa Rica to identify Brevipalpus species associated with these economically vital crops. The investigation revealed the presence of five Brevipalpus species, including B. yothersi, a major vector of citrus leprosis cilevirus in numerous countries, B. papayensis, previously linked to coffee ringspot dichorhavirus in South America, B. phoenicis, B. californicus, and B. azores, vectors of dichorhaviruses causing citrus leprosis diseases. Despite their presence, no viral symptoms were observed in the plantations surveyed. Generalized linear models revealed different distributional patterns across altitude gradients; the probability of occurrence of B. papayensis increased with altitude, whereas the detection of B. yothersi declined at higher elevations across both hosts. The other three species occurred at very low frequencies; B. californicus and B. phoenicis were positively associated with altitude, though the latter only on Citrus. In contrast, B. azores slight decline with altitude on Citrus. In addition, the study documented 17 predatory mite species, 14 species belonging to Phytoseiidae and three to Stigmaeidae. This study examines the relationship between Brevipalpus distribution and altitude using empirical survey data across an entire country, demonstrating that Brevipalpus distributions in Costa Rica on these two hosts are strongly shaped by altitude and host, with species responding in contrasting ways. Such ecological differentiation has important implications for predicting virus risk under changing environmental conditions and provides a critical baseline for designing integrated pest management strategies in citrus and coffee production systems.

Optimizing nutrient transfer across trophic levels has become an important approach to enhance the biological efficiency and sustainability of predator-prey rearing systems supporting augmentative biological control. This study examined how dietary enrichment of the factitious prey Tyrophagus putrescentiae (Schrank) influences its biochemical composition and subsequent effects on the demographic performance of the predatory mite Amblyseius swirskii Athias-Henriot; one of the most widely used biocontrol agents in protected crops. Eight dry diets were tested, including a basal mixture (Diet 1: wheat bran + baker's yeast) and seven enriched formulations varying in animal- and plant-derived components. After three generations of prey rearing, we quantified the biochemical composition (protein, triacylglycerol, glycogen) of T. putrescentiae and the corresponding life table parameters of A. swirskii. Diets containing both animal and plant supplements; particularly Diet 6 (basal diet + cat food + mixed pollen), Diet 7 (basal diet + starch + dog food + cat food + mixed pollen), and Diet 8 (basal diet + dog food + cat food + mixed pollen + vitamin mix); significantly enhanced predator fecundity, shortened developmental time, and increased the intrinsic rate of increase (r), with Diet 7 achieving the most balanced performance. Glycogen reserves in the prey were positively correlated with predator reproduction, underscoring the importance of carbohydrate-based energy allocation in trophic transfer. These results establish a mechanistic nutritional framework to improve the quality and productivity of mass-reared predatory mites, directly supporting the efficiency and scalability of biological control programs.

Mycoacaricides represent a promising alternative for managing resistant tick populations. This study evaluated the efficacy of corn oil-based Cordyceps javanica formulations against non-parasitic stages the southern cattle tick Rhipicephalus microplus under laboratory and semi-field conditions. Additionally, fungal persistence in soil and possible alterations in soil composition were assessed using ATR-FTIR spectroscopy combined with chemometric analysis. Corn oil (1%, 3%, and 5%) combined with 0.01% silicone oil did not affect conidial germination (> 98.4%). Corn oil and C. javanica suspensions alone yielded larval average mortality of 20.1% and 18.8%, respectively, 15 days after the treatment. When formulated in corn oil, averages of larval mortality ranging from 64.1% on day 5 to 100% on day 15, indicating a synergistic effect between fungus and oil. Corn oil alone resulted in a female tick control percent ranged from 20.5 to 73.3%, while the fungus alone achieved 28.2% and 14.9% control at 10⁷ and 10⁸ conidia/mL, respectively. All fungus-oil formulations significantly reduced female reproductive efficiency, achieving 90-100% tick control. Under semi-field conditions, the 10⁸ conidia/mL + 3% corn oil formulation reduced larval recovery from Urochloa decumbens pots by 98.6% compared to the oil and silicone control. Thirty days after application, C. javanica persisted in soil at 2.1 ± 0.3 × 10⁵ CFU/g (39.4% recovery). ATR-FTIR analysis showed no detectable alterations in the soil's chemical profile following application of any formulation. These results highlight the potential of oil-based C. javanica formulations as an effective and sustainable tool for integrated tick management in livestock systems.

The potato tuber moth (PTM), Phthorimaea operculella (Zeller), is a globally significant pest that attacks potatoes and many other Solanaceous crops. The ectoparasitic mite Pyemotes zhonghuajia Yu, Zhang & He is a promising biological control agent for PTM. This study investigated the effects of PTM larval body size (small and large) and P. zhonghuajia density (50, 150, and 250 mites) on host paralysis, as well as on the development and reproduction of P. zhonghuajia, aiming to optimize its mass production and application in PTM management. Our results showed that P. zhonghuajia females took significantly longer to paralyze and kill large PTM larvae at the lowest density (50 mites). Increasing mite density significantly decreased the parasitism rate per host, likely due to increased mutual interference among host-searching mites. However, the number of P. zhonghuajia females feeding on a single host increased significantly with mite density, resulting in smaller opisthosoma and fewer offsprings, suggesting food competition among females. Host size had a significant positive effect on opisthosoma size, offspring number per opisthosoma, and total offspring produced by P. zhonghuajia female, indicating that larger hosts provide more nutrients. The total number of offspring produced by P. zhonghuajia females from a host of a given size was similar across mite densities, suggesting that an optimal ratio of 50 P. zhonghuajia females per PTM larva is recommended for laboratory mass rearing and field augmentative release.

Several arthropod pests infest almond orchards in California's Central Valley, United States, which produces ~ 80% of the almonds globally. Some are key pests, while others are minor but can cause economic damage due to fluctuations in environmental factors from year to year. Thus, keeping pest levels below the economic injury level is key for sustainable and profitable almond production. As a part of the integrated pest management (IPM) concept, record-keeping for the occurrence of various pests using an adequate sampling plan aids in developing a future pest management program. Thus, we tested sampling methods for the brown mite, Bryobia rubrioculus Scheuten, which is becoming an increasing problem in almond orchards in California. We sampled three almond orchards in the northern San Joaquin Valley from February to July at bi-weekly intervals. We used a tree-band trap on the tree trunk to collect mites from the lower part of the canopy and trunk, and leaf and shoot tuft samplings to collect mites from the top canopy of the plants. Consistent with all orchards, we collected the highest number of mites from shoot tufts than from tree bands, and the lowest number from leaves. Our results provide a foundation for monitoring B. rubrioculus populations in commercial almond orchards in California.

Just a handful of mite species are suspected inhabiting the dust of houses within arid areas of the Arabian Peninsula. In this study, we identified and compared the house dust mite diversity in three different climatic areas within Saudi Arabia. Sampling was carried out over one year and two months, with samples collected in the desert, the coast, and in the highlands. It reviews all known mites of house dust of Saudi Arabia. A total of 998 mites were collected belonging to 23 species in 14 families. Pyroglyphidae (Astigmata) were the most abundant. The interaction among pyroglyphid species in the climatic regions was analysed. While variation in abundance of Pyroglyphidae among regions was weak, there was a strong desert region Cheyletus eruditus-Dermatophagoides farinae association, perhaps explaining that D. farinae populations from the desert have become C. eruditus' favourite prey. Another interesting association is that of Pyroglyphidae with Acaridae. D. pteronyssinus shows significant numerical dominance in the highlands. A newly discovered species of Dermatophagoides did not interact with any of the other 2 species and was restricted to the coastal region. Dermatophagoides n. sp. and Cheletopsis sp. can be used as markers of location in forensic analyses (provenance), based on their unique association with the coast and desert, respectively. A new species of Dermatophagoides has been identified. Five species are new to Saudi Arabia and the Arabian Peninsula including house dust, ten species are new to the house dust mite fauna of Saudi Arabia and the Arabian Peninsula but have been recorded as storage mites, totalling 15 new house dust mites for the Arabian Peninsula. Two species are new to house dust in Saudi Arabia, but already known from house dust in Kuwait. Of the fifteen new house dust mites for the Arabian Peninsula, five species are new to the dust mite fauna worldwide: Prostigmata: Cheletopsis sp. (Cheyletidae); Mesostigmata: Proctolaelaps pygmaeus (Melicharidae), Macrocheles muscaedomesticae (Macrochelidae); and Oribatida: Oribatula tibialis (Oribatulidae), and Ceratozetes sp. (Ceratozetidae).

The morphological identification of chiggers has traditionally been the primary method used in taxonomic research on these mites. However, this approach is often inadequate and can lead to incorrect conclusions. The difficulties in identifying these mites primarily arise from the limited resolution of morphological traits used for diagnosis at both the genus and species levels. As a result, there is an increasing need to rely on additional criteria, particularly molecular analyses, to confirm the status of various genera and species. This study aimed to clarify the taxonomic status of species within Hirsutiella, particularly focusing on Hirsutiella willmanni, which has been considered a synonym of H. zachvatkini by some researchers. The larvae were collected from Clethrionomys glareolus, at various locations across Poland, following previous literature reports of the presence of both Hirsutiella species in the country. Based on an integrative approach that includes morphological as well as molecular data, specifically from the mitochondrial cytochrome c oxidase subunit I (COI) and large ribosomal subunit (28S rRNA) markers, we confirm the separate species identity of H. zachvatkini and H. willmanni. The results confirm the higher effectiveness of the 28S gene in distinguishing between chigger species. The larvae of H. willmanni are redescribed, accompanied by a revised diagnosis of larvae of H. zachvatkini. Genetic differentiation between populations of H. zachvatkini from the Carpathians, Sudetes, and the lowland and upland areas north of the mountain ranges has been revealed.

The coconut mite, Aceria guerreronis, colonizes the fruit perianth, a region covered by floral bracts, which hinders its control. Its attack causes epidermal necrosis, fruit deformation, and premature fruit drop, with yield losses ranging from 10% to 70%. Infestations generally begin in fruit up to three months old. Since the age of the fruit at the time of infestation can influence not only the severity of damage but also fruit abortion, these aspects were investigated through field experiments. Fruit aged 2 to 5 months were artificially infested with A. guerreronis, and every 15 days, necrotic area and number of aborted fruit were quantified until harvest (≈ 8 months). Both damage severity and abortion rate were significantly higher in younger fruit (2-3 months) than in older fruit (4-5 months); however, damage severity had no direct influence on abortion. These results indicate that the extent of necrotic lesions is not a determining factor for fruit abortion. Despite significant damage observed in some infested fruit, many remained attached to the plant and continued to develop. Others, however, aborted without any necrotic lesions. These findings suggest that other factors, such as physiological mechanisms of tolerance or compensation by the host plant, may influence fruit retention. Understanding these dynamics is essential to improve pest management strategies and avoid overestimating potential yield losses associated with mite infestation.

The two-spotted spider mite, Tetranychus urticae Koch, is a significant pest in strawberry cultivation worldwide, causing substantial crop damage and economic losses. Biological control using predatory mites such as Amblyseius swirskii Athias-Henriot and Neoseiulus californicus (McGregor) is an essential component of integrated pest management (IPM) strategies. However, the efficacy of these natural enemies can be negatively affected by acaricide applications. This study assessed the sublethal effects of two acaricides; bromopropylate, a synthetic agent, and GC-Mite, a botanical formulation, on the life history and population growth parameters of A. swirskii and N. californicus feeding on T. urticae in strawberry crops. Acute toxicity assays demonstrated that both predatory mites exhibited significantly lower susceptibility to these acaricides than T. urticae, with A. swirskii showing the greatest resistance. Perinatal exposure to LC₂₅ residue of bromopropylate and GC-Mite prolonged immature development, reduced adult longevity, and decreased fecundity in both predatory mite species. N. californicus experienced more pronounced negative effects, including marked declines in survival rates and reproductive output, whereas A. swirskii displayed greater resilience and more stable reproductive potential. Population growth parameters, such as the intrinsic rate of increase (r) and net reproductive rate (R₀), declined significantly under acaricide treatments, with bromopropylate producing stronger adverse effects than GC-Mite. These results emphasize the relative compatibility of GC-Mite within IPM programs due to its lower toxicity to beneficial predatory mites. Careful selection and application of acaricides that minimize harm to natural enemies are crucial for sustainable management of T. urticae in strawberry cultivation.