Experimental and Applied Acarology最新文献

Acari, including mites and ticks, pose significant challenges in agriculture, horticulture, and medicine. Among these, agricultural concerns are particularly critical, as many mite species directly affect crop health and productivity. The genome sizes of Acari vary widely, reflecting their diverse ecological roles and life history traits. This variation often corresponds to differences in reproductive strategies, parasitic behaviors, and adaptation to specific environments. Here, to better understand evolution trends in Acari, we (1) estimated the genome size of six mite species using flow cytometry, (2) compiled publicly available genome data for additional Acari species, and (3) analyzed the relationships between genome features (size, repetitive elements, GC content, gene numbers) and ecological or life history traits. Our findings reveal that predatory and parasitic Acari, particularly blood-feeding species, tend to have larger genomes compared to herbivorous and microbivorous species, suggesting that diet and ecological roles may drive genome expansion. Additionally, genome size correlates positively with repetitive elements, which significantly contribute to genome variability. Furthermore, larger genomes are linked to higher GC content and gene numbers, reflecting increased functional complexity and genome stability. These findings align with hypotheses on genome size determinants, highlighting the influence of ecological and evolutionary pressures on Acari genome architecture. Understanding their genome structure is crucial for uncovering the genetic basis of their ecological and physiological diversity, which underpins their adaptability and resilience. Such insights are vital for developing targeted pest management strategies to mitigate their agricultural impact and promote long-term sustainable practices.

Chilli yellow mite is a major pest of chilli, which causes significant damage to both leaves and fruits. Synthetic acaricides, though widely used for control, pose environmental risks and often give unsatisfactory results due to pest resistance. Therefore, this study aimed to enhance the resistance of chilli plants against mite by applying silicon (Si), a natural element, in two forms- CaSiO₃ and K₂SiO₃, at concentrations of 0.1%, 0.5% and 1.0%. Results showed that Si application significantly reduced mite infestation while having no effect on their natural predator, the ladybird beetle. CaSiO₃ at 0.1% Si led to the lowest leaf infestation rates (7.6 ± 1.5%, 4.4 ± 0.4% and 2.4 ± 0.4% after the first, second and third sprays, respectively), and produced the highest number of healthy fruits at both the first and second harvests (345.8 ± 5.3 g/plant and 335.0 ± 4.2 g/plant, respectively). Si treatment increased the thickness of both the upper and lower leaf epidermis, especially with CaSiO₃ and K₂SiO₃ at 1.0% Si. It also elevated the levels of the stress-responsive hormones salicylic acid and jasmonic acid relative to the control, particularly with CaSiO₃ at 0.1% Si. Principal component analysis revealed that mite infestation was negatively correlated with both acid levels and leaf epidermis thickness. Thus, Si application presents a promising, eco-friendly strategy for managing mite infestations in chilli plants.

Euseius nicholsi (Acari: Phytoseiidae), has great potential for biological control applications owing to its broad distribution, capability of preying on detrimental mites amid surging challenges of pesticide resistance. In this study, genetic diversity and molecular phylogeography of E. nicholsi were investigated based on mitochondrial COI and 12 S rRNA sequence data derived from 30 populations in China. 86 haplotypes of the COI gene and 37 haplotypes of the 12 S rRNA gene were detected signifying its genetic diversity and great potential for bio-control programs. The results of Tajima's D, Fu'Fs and mismatch distribution histogram showed that its population evolution followed a neutral evolutionary model. The analyses of spatial genetic structure manifested that the correlation between the geographic space distance and genetic distance of all geographic groups were not apparent. Additionally, it's distribution in China can be divided into four biogeographical regions. To our knowledge, the current study constitutes the first research on molecular phylogeography of E. nicholsi with two mitochondrial gene-markers from 30 geographic populations, expanding its recording range, preliminarily analyzed the fauna of E. nicholsi and could help shed light on its conservation biology and practical utilizations in bio-control programs.

Vegetation cover in vineyard inter-rows is known to enhance the abundance and richness of Phytoseiidae predatory mites on the vine canopy. However, the extent to which these mites disperse ambulatory along vine stocks from one compartment to another remains poorly understood. This study investigates the ambulatory dispersal of Phytoseiidae mites in a Mediterranean vineyard in southern France. Specifically, we evaluated (i) whether Phytoseiidae disperse bi-directionally along the vine stock, (ii) whether the presence of inter-row vegetation enhances dispersal toward vine, and (iii) whether mowing affects dispersal by altering shelter and food availability. Samplings were conducted on inter-row vegetation and vine canopies across three systems (bare soil, sown, and spontaneous vegetation). Traps were placed along vine stocks during two sampling periods to assess the effect of mowing. An average of 4.59 Phytoseiidae were captured per trap, belonging to five species. The dominant species, Typhlodromus (Anthoseius) cryptus Athias-Henriot was only found in traps, suggesting habitat specialization. Two other species, Typhlodromus (Anthoseius) recki Wainstein and Typhlodromus exhilaratus Ragusa, were present in both vegetation compartments and in traps, indicating potential ambulatory dispersal. Contrary to expectations, the presence of inter-row vegetation had limited influence on overall Phytoseiidae abundance and richness in traps. However, increased numbers of T. (A.) recki and T. exhilaratus on traps following mowing suggest that disturbance may induce ambulatory dispersal. These findings highlight the role of vegetation structure and its management in shaping Phytoseiidae distribution. Further research is however needed to clarify the mechanisms driving these patterns and the role of inter-row management in enhancing biological control.

Polyphagous pests often undergo the phenomenon of host-switching to expand their diet and enhance their environmental adaptability. The Tetranychus turkestani is the dominant mite pest in the northern Xinjiang region. To evaluate the influence of feeding experiences and its microbiome on the adaptation of T. turkestani to soybean hosts. we constructed age-stage two-sex life table and 16 S rDNA sequencing technology, the effects of the pre-host on the adaptability of T. turkestani to soybeans and the microbiome community were systematically evaluated, and the correlation between the two was further explored. The results show that: before host-switching, T. turkestani exhibited the highest intrinsic rate (0.277 d ^-1) and net reproductive rate (124.500) on the soybean host. The r (0.185 d^-1) and R₀ (37.488) of T. turkestani are lowest when reared on Amaranthus retroflexus. After the host was switched to soybean, both the r and R₀ of T. turkestani increased. Similarly, the Chao1 index of T. turkestani exhibited a significant increase. When T. turkestani feeds on A. retroflexus, Wolbachia (97.01%), an insect endosymbiont, is the predominant microbiome. In contrast, when it feeds on Chenopodium album, Spiroplasma (54.59%) becomes the dominant microbiome. After the host was switched to soybean, the composition of microbiome in T. turkestani became similar to that of populations feeding on soybean. Correlation analysis revealed that Spiroplasma and Wolbachia were significantly positively correlated with both the oviposition period in host-switching of T. turkestani.

Phytoseiid mites (Mesostigmata: Phytoseiidae) are a diverse family of predatory arthropods that play a crucial role in controlling herbivorous mite and insect populations in agricultural ecosystems. Within this family, the genus Euseius Wainstein includes generalist predators known for their ability to utilize alternative food sources such as pollen, making them valuable in both augmentative and conservation biological control strategies. Among these, Euseius finlandicus (Oudemans) is widely distributed across various agroecosystems in Türkiye, particularly in citrus orchards, and is recognized for its potential contribution to sustainable pest management. This study evaluated the acute toxicity and sublethal reproductive effects of five acaricides commonly applied in citrus cultivation-abamectin, etoxazole, fenbutatin oxide, pyridaben, and spirodiclofen-on the eggs, larvae, and adult females of E. finlandicus. The experiments were conducted under standardized laboratory conditions (25 ± 2 °C, 65 ± 10% relative humidity, and a 16:8 h light: dark photoperiod). In addition to assessing the highest manufacturer-recommended concentrations, differential dose-response effects were investigated in accordance with the toxicity levels observed. Both abamectin and pyridaben demonstrated low ovicidal and marked larvicidal activity and induced complete mortality (100%) in adult females within 24 h, thereby precluding the assessment of their impact on fecundity. Etoxazole caused moderate egg (19.17%), complete larval, and low adult mortality (10.34%). Fenbutatin oxide and spirodiclofen were associated with relatively low toxicity across all developmental stages evaluated, with adult mortality remaining below 13%. Regarding reproductive parameters, neither etoxazole nor fenbutatin oxide significantly impaired oviposition compared to the control, while spirodiclofen was associated with a reduction in fecundity. Based on these findings, fenbutatin oxide and spirodiclofen are considered compatible with E. finlandicus within the context of integrated pest management. In contrast, abamectin and pyridaben exhibited deleterious effects across larva and adult stages and are deemed incompatible. Etoxazole warrants cautious use due to its stage-specific toxicity. Consequently, field and semi-field trials are essential to further elucidate the ecological risk profiles of abamectin, etoxazole, and pyridaben under realistic agronomic conditions.

Leipothrix violarius (Acariformes: Eriophyoidea) is a phytophagous mite specialized in feeding on plants from the genus Viola. It has been recorded on five host species, including Viola uliginosa, which is rare or endangered in much of its range. Despite taxonomic revisions, little is known about the biology or host specificity of L. violarius. In this study, we compared the effects of V. uliginosa and V. odorata on the development, survival, and population parameters of L. violarius, and assessed its host range using selected ornamental and naturally occurring violets. Development from egg to adult took approximately seven days on both host plant species, with no sex-related differences. However, mites reared on V. odorata exhibited faster egg development and greater population increase per generation than those reared on V. uliginosa. Population growth occurred on all tested host species, although mite performance varied. Viola plants produce cyclotides-bioactive cyclic peptides with antimicrobial and insecticidal properties. The observed differences in mite performance may reflect interspecific variation in cyclotide content or composition, suggesting a role for these compounds in plant resistance. Due to its narrow host range and epidermal feeding behavior, L. violarius offers a promising model for studying plant-mite interactions at the surface level. This system may help clarify how cyclotides mediate and respond to herbivory in Viola species.

Neoseiulus bicaudus Wainstein (Acari: Phytoseiidae) serves as an effective biological control agent for managing spider mites and small pests. The cold acclimation of predatory mites significantly influences their distribution patterns and survival at low temperatures. In this study, we examined the effects of cold acclimation on the cold tolerance of N. bicaudus and investigated the physiological responses associated with different durations of cold acclimation (6-hour: 3 °C for 6 h; 24-hour: 3 °C for 24 h; 7-day: 9 °C for 7 day) using metabolomics. Cold acclimation significantly enhanced the low-temperature survival capability of N. bicaudus. Moreover, this process elicited a range of physiological and metabolic adaptations in predatory mites. Specifically, a 7-day cold acclimation period yielded the most pronounced changes. The cold acclimation response of 24-hour and 7-day was attributed to the reprogramming of metabolites involved in sugar metabolism (e.g., D-fructose and maltose), amino acid metabolism (e.g., DL-phenylalanine and L-serine), and lipid metabolism (e.g., octanoate, (9Z)-hexadecenoic acid, cholesterol, glycerophospholipids, lysophospholipids). Additionally, 24-hour acclimation at 3 °C enhanced the activities of antioxidant enzymes such as superoxide dismutase and peroxidase, along with increased levels of antioxidants like zeaxanthin, coenzyme Q10, and retinol. After 7 days of cold acclimation, the levels of various antioxidants, including glutathione, zeaxanthin, γ-tocopherol, retinol, xanthine, and carnosine, were markedly elevated. Collectively, these physiological adaptations are strongly correlated with the maintenance of homeostasis in N. bicaudus under low-temperature stress, suggesting they collectively contribute to its enhanced survival capacity.

Tetranychus urticae Koch (Acari: Tetranychidae) is a significant pest for crops. Life history and population growth projection for T. urticae were conducted on apple cultivars Gala and Golden Delicious under controlled conditions of 26 ± 1 °C, 70 ± 5% humidity, and a photoperiod of 16:8 (L: D) hours. The 0.025th and 0.975th percentile confidence intervals for T. urticae population parameters and survival rates were determined using the bootstrap resampling technique with 100,000 resamples, and differences were fitted via the paired bootstrap method. The developmental durations and pre-adult survival rates of T. urticae were similar for both cultivars. However, female fecundity was higher on the Gala cultivar, averaging 59.71 eggs per female, compared to 39.01 eggs on Golden Delicious. The Gala cultivar showed the highest values for R₀ (41.80 offspring), r (0.2127 day⁻¹), and λ (1.2370 day⁻¹), while the Golden Delicious had lower values (23.40 offspring, 0.1690 day⁻¹, and 1.1841 day⁻¹, respectively). This indicates that T. urticae has better fitness on the Gala cultivar than on Golden Delicious. Projection models for ten T. urticae eggs over 60 days indicate potential population increases to 174 on Gala and 66 on Golden Delicious without control measures. However, under controlled conditions, populations remained below 20 individuals on both cultivars. Integrating life table data with the age-stage structure of both sexes reveals optimal timings for population management. Future studies will improve the understanding of T. urticae interactions with host plants and abiotic factors, leading to more accurate conclusions.

During ornithological research conducted at the Milicz Fishponds Nature Reserve (Barycz Valley Landscape Park, southwestern Poland) from May to July 2024, a total of 245 birds were captured. Four ticks were collected: two Ixodes ricinus larvae and two Haemaphysalis concinna nymphs. We present the first confirmed record of H. concinna parasitising a great reed warbler (Acrocephalus arundinaceus) in Poland. Identification of H. concinna was based on both morphological identification keys and molecular analysis of the COI gene. This finding expands current knowledge on the biodiversity of ticks parasitising birds in Poland and highlights the need for further research on the role of migratory birds in the dispersal of ticks across Central Europe.