Search Results (33)

Fungi of the genus Trichoderma have attracted attention because of their potential activity against phytophagous mites; however, information regarding their non-target effects on predatory mites remains limited. This study evaluated the effects of spore suspensions and secondary metabolites of Trichoderma afroharzianum Tr132 and Trichoderma virens Tvr2 on three predatory mite species widely used in biological control programs: Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius swirskii. Predator egg hatchability and adult mortality were assessed under laboratory conditions. Spore suspension treatments did not significantly affect egg hatchability, which remained high (97–99%) across all predator species. In contrast, secondary metabolites slightly reduced egg hatchability to 94–96%, compared with 99.5% in the control. Exposure to spore suspensions caused moderate mortality in adult predatory mites, increasing from 10 to 13% at 3 days post-application (dpa) to 15–19% at 6 dpa. Secondary metabolites produced higher mortality that increased over time, reaching 9–11% at 1 dpa, 17–18% at 3 dpa, and up to 22–25% at 6 dpa. Mortality responses were similar among predator species. Overall, Trichoderma applications had minimal effects on predator egg hatchability but caused moderate mortality in adult predatory mites, particularly following exposure to secondary metabolites. These findings highlight the importance of evaluating the compatibility of Trichoderma-based products with beneficial predatory mites before their integration into IPM programs. Full article

Mite species of the genus Cenopalpus are phytophagous pests associated with fruit and ornamental crops. Although the genus is primarily distributed in the Palearctic region, increasing international trade of plant material has created repeated opportunities for its unintentional transport across borders. To support improved awareness of emerging biosecurity risks, international quarantine interception records were analyzed from Australia, Laos, Malaysia, New Zealand, Singapore, South Africa, and the United States of America. A total of 98 interceptions were documented between 1981 and 2024, exclusively reported by New Zealand, South Africa, and the USA, while no Cenopalpus spp. mites were intercepted in Australia, Laos, Malaysia, or Singapore. Six species were identified, with Cenopalpus pulcher being the most frequently detected, followed by C. lanceolatisetae and C. officinalis. Interceptions were primarily associated with fruit crops, particularly apples and stone fruits, frequently with origins in Europe and the Middle East. Several records represent the first detection of Cenopalpus in trade originating from countries within Africa, Asia, the Americas, and Oceania. Taxonomic uncertainty associated with Cenopalpus mites likely limits accurate identification in interception records, highlighting the need for improved diagnostic expertise. The implications of these findings for plant biosecurity programs, including surveillance and diagnostic priorities, are discussed. Full article

The objective of this study is to evaluate the effects of botanical oils on the mortality of the phytophagous mite Tetranychus urticae, the predatory mite Amblyseius swirskii, and on gas exchange in papaya seedlings. Two vegetable oils (soybean and corn), two essential oils (lavender and oregano), a synthetic pesticide (abamectin), and a control (water) were evaluated on papaya seedlings infested with T. urticae. In laboratory assays, within the first day after application, abamectin caused 100% mortality of T. urticae adults, followed closely by soybean (96%), corn (94.7%), and lavender (94.7%) oils. In A. swirskii, abamectin caused 100% mortality within 24 h; at 72 h, corn and lavender oils reached 96%, while oregano oil caused the least mortality (67.3%). In field trials, both abamectin and botanical oils statistically reduced eggs per leaf 24 h after application relative to the control, and a similar pattern was observed for nymphs 48 h after treatment. Botanical oils equaled abamectin in T. urticae adult suppression by 72 h, and soybean caused complete adult mortality by day 14. Regarding gas exchange, abamectin significantly affected the photosynthesis and transpiration processes. Thus, botanical oils represent viable biorational options for managing T. urticae in papaya, with lower ecological and physiological costs than abamectin. Full article

Eriophyoidea (Acariformes), a superfamily of obligate phytophagous and highly host-specific mites, comprises four early-diverging lineages (Pentasetacidae, Phytoptidae s. str., Nalepellidae, and Eriophyidae s.l.) with unresolved inter-relationships. The clade Phytoptidae s. str. is restricted to angiosperms and includes a group of six genera associated with palms (Arecaceae) and classified in tribes Mackiellini and Phytoptini. Global distribution patterns of Phytoptidae s. str. are biased towards the Americas and Europe. Current knowledge of Asian palm-associated phytoptids is limited to a single record of Borassia from India and the new Calventer arengii n. g. et sp. (Sierraphytoptinae: Mackiellini) described here as a vagrant on the lower surface of fronds of Arenga westerhoutii Griff. (Arecaceae) from Vietnam. Maximum likelihood COI analyses did not support the monophyly of Mackiellini but revealed a sister-group relationship between Mackiella and Calventer and questioned the taxonomic position of Borassia. Notably, Calventer possesses one of the most reduced chaetoms in Phytoptidae, illustrating a recurring trend of setal loss across Eriophyoidea. Plesiomorphically, females of eriophyoids have 65 setae, with most being prone to homoplastic reduction; however, a stable subset (h2, 3a, emp, and ω) is consistently retained. Excluding these “stable setae,” the remaining chaetom can be expressed as a “setal formula” incorporated into generic diagnoses for the efficient, rapid delimitation of genera. Full article

The two-spotted spider mite (Tetranychus urticae Koch) (Acari: Tetranychidae) is one of the most widespread and destructive phytophagous mite species, occurring across all climatic zones worldwide. Currently, the control of spider mites in crop protection relies primarily on chemical acaricides. However, the selection of resistant populations to their active ingredients is reducing their efficacy. The aim of the present study was to assess the susceptibility of T. urticae to a native isolate of entomopathogenic nematodes, Steinernema feltiae Filipjev ZWO21, under laboratory conditions. The experiment was conducted using Petri dishes, each containing 22–28 adult T. urticae. Infective juveniles (IJs) of the nematodes were then applied at a dose of 8000 IJs per dish (±300 IJs per mite). Petri dishes with mites treated with nematodes were placed in a Sanyo incubation chamber at 25 °C and 60% relative humidity. After three days, dead mites were collected from the Petri dishes and dissected, and mortality was subsequently determined. The present study confirmed that the S. feltiae ZWO21 isolate exhibited considerable potential for the biological control of T. urticae, causing 37.5–83.3% (mean 57.0%) mortality in this pest species. Although this result indicates a moderate efficacy when nematodes are applied alone, it also underscores the relevance of further research into their integration with other control strategies, including acaricides, within integrated pest management (IPM) programmes. Full article

Phytophagous mites are considered pests in fruit crops, such as blackberries (Rubus spp. L.). These pests affect fruit quality and commercial value. This study aimed to evaluate the fluctuation of phytophagous mite populations and their impact on the quality of cultivated and wild blackberries in Jalisco, Mexico. Monthly sampling was carried out from November 2023 to May 2024. Mite families such as Diptilomiopidae, Eriophyidae, Tydeidae, Tarsonemidae, Tenuipalpidae, and Tetranychidae were identified, with a total of 6438 mites in the samples. An increase in mite populations was observed in March on cultivated blackberries and in April on wild ones, coinciding with the onset of plant development. The Eriophyidae family showed the highest relative abundance, with 34.2% in cultivated blackberries and 31.7% in wild ones in 2024. Quality parameters were evaluated in healthy and damaged blackberries. Damaged cultivated fruits showed lower weight (4.49 ± 1.44 g), smaller diameter (18.11 ± 2.00 mm), lower vitamin C content (4.76 ± 1.53 mg/100 g), and higher acidity (80.07 ± 19.10%). This study enabled the identification and monitoring of different mite families in blackberries, as well as an understanding of their population dynamics and impact on fruit quality. Full article

Stethorus punctillum Weise, a predatory beetle attacking phytophagous mites in northwest China, remains underutilized for biological control. Current over-reliance on synthetic acaricides necessitates evaluation of their non-target effects on this predator, particularly their safety and sublethal impacts. Here, we assessed the acute toxicity of four acaricides to S. punctillum in laboratory bioassays and then focused on sublethal impacts of abamectin on adult predation efficiency and lifespan. Based on the LC₅₀ values, the acute toxicities of the four acaricides tested against S. punctillum larvae and adults both ranked as follows (from greatest to least): abamectin > pyridaben > spirotetramat > petroleum oil. All acaricides exhibited selective toxicity (STR: 2.16–182.49) with moderate to low risk (SF: 0.46–8.71). Notably, petroleum oil, despite showing the lowest acute toxicity to S. punctillum, posed the highest risk to larvae (SF: 0.46–0.77). Abamectin exposures at LC₂₀ or LC₅₀ significantly compromised S. punctillum adults, prolonging prey handling time (females: 33–100%; males: 40%), reducing maximum daily predation (females: 25–50%; males: 29%), and shortening adult lifespan (females: 2.34–3.17 days; males: 3.95–5.08 days). This study assessed the safety of four commonly used acaricides for S. punctillum, revealing abamectin-induced impairments to key biological traits. Our findings offer critical insights for risk-aware acaricide selection and integrated spider mite management strategies in agroecosystems in northwest China. Full article

Phytophagous mites are herbivores that feed on various economically important plants, such as soybean [Glycine max (L.) Merril]. Thus, our objective is to evaluate the oxidative stress stage of soybean plants infested by Tetranychus ludeni Zacher. Leaflets from three trifoliate leaves were pooled to form composite samples for each exposure time and evaluated at the following evaluation times: 0 h, 20 min, 6 h, 12 h, 24 h, and 48 h. In the initial phase of infestation (20 min), an oxidative burst was observed, represented by prominent hydrogen peroxide accumulation rather than superoxide radicals. This oxidative burst occurred in parallel to a strong increase in the antioxidant activities of catalase, ascorbate peroxidase, and glutathione S-transferase, but not in that of superoxide dismutase. These changes likely reflected an enhanced activation of signaling pathways involved in the oxidative stress response. After this initial phase, from 20 min to 6 h, a prominent decrease occurred in catalase, ascorbate peroxidase, and glutathione S-transferases activities, despite the hydrogen peroxide levels remaining significantly elevated, along with a marked but transient increase in the reduced glutathione content and proline. Interestingly, superoxide dismutase activity increased significantly after 6 h in parallel to lipid peroxidation, whereas the content of hydrogen peroxide remained elevated until 12 h of infestation. By the final evaluation, after 48 h of infestation, some redox indicators remained altered in relation to control plants, but in a state of moderate redox stress. Thus, in an unprecedented way, our data suggest that T. ludeni infestation triggered a moderate oxidative stress response in soybean plants. These findings highlight that proper monitoring and management can reduce economic losses without resorting to aggressive chemical interventions. Full article

The highly variable ’leafscapes’ of plants across the world represent billions of square metres of mite habitat. The phytoseiid mites (Acari: Phytoseiidae), an extremely species-rich group of mostly generalist predators, are providers of ecosystem services for humanity worth many hundreds of millions of dollars annually by helping suppress phytophagous mites and insects in forests, agro-ecosystems, shade-houses and home gardens. In this study, the phytoseiid mite assemblages on the leaves of four species of common tree species, namely oak (Quercus cerris var. cerris), poplar (Populus deltoides, P. nigra) and walnut (Juglans regia), were compared. The three data sets used were generated in three independent seasonal studies in Samsun Province, Türkiye, between 2018 and 2022. In total, mite species in 18 families, including 15 families on walnut, were recorded. Nineteen phytoseiid species in 13 genera, Amblydromalus, Amblyseius, Euseius, Kampimodromus, Neoseiulella, Neoseiulus, Paraseiulus, Phytoseius, Transeius, Typhlodromina, Typhlodromips, Typhlodromus and Typhloseiulus, were collected. Only Eusieus amissibilis was collected from all three tree genera, whereas 14 species were collected from only one tree genus. Shannon diversity and Jaccard similarity indexes were calculated for mite families and phytoseiid genera and species. Potential reasons for the observed differences in the phytoseiid assemblages on the different host trees are explored in depth. In the ‘big picture’, global biodiversity, likely including many undescribed phytoseiid species, is threatened by widespread habitat degradation and destruction, especially in the tropics, and accelerating climate change, and rapidly stopping them is imperative. Full article

Phytoseius plumifer (Canestrini and Fanzago) and Euseius scutalis (Athias-Henriot) (Phytoseiidae) are generalist predatory mites important in controlling phytophagous mites on some agricultural crops. The biology of both species as potential biological control agents of the grape erineum mite, Colomerus vitis (Pagenstecher) (Eriophyidae) on grape leaf disks was studied in the laboratory at 33 ± 1 °C, 60%RH, 12:12 h L:D. The developmental time, survival, and reproductive parameters of P. plumifer and E. scutalis on C. vitis, date palm pollen as well as C. vitis plus date palm pollen were investigated. Both predators, P. plumifer and E. scutalis, thrived on the mixed diet of C. vitis and date palm pollen resulting in a shorter developmental time (6.16 and 6.69 days, respectively), higher oviposition rate (2.11 and 1.96 eggs/female/day, respectively), and higher intrinsic rate of increase (0.251 and 0.229 per female/day, respectively) than on any other diet. Date palm pollen was an adequate alternative food source for P. plumifer and E. scutalis. The results suggest that both predators have good potential to suppress C. vitis populations and that date palm pollen can support the population establishment of both predators in the absence or scarcity of the main prey in the environment. We discuss the relevance of our results for the biocontrol of C. vitis. Full article

Soybeans are a valuable crop in many countries of the world. To obtain stable yields, it is necessary to consider the activities of arthropods, both beneficial and destructive. The results of this study indicate high biodiversity. Most of the insects that feed on soy are polyphagous. In the years favorable for their development, omnivorous pests pose a serious threat to soybeans. The species composition of arthropods on soybeans of the Krasnodar and Stavropol territories of the Russian Federation during the years of the study was represented by 212 species (210 species of insects and 2 species of mites), including 101 species of phytophagous insects, which accounted for 48.5% of the total fauna and 109 species of entomophagous insects (51.7%). Most of the entomophages were parasitic Hymenoptera belonging to such families as Ichneumonidae, Braconidae, Aphidiidae, Eurytomidae, Ormyridae, Pteromalidae, Encyrtidae, Eupelmidae, Eulophidae, Elasmidae, Scelionidae, Platygastridae, and Chrysididae. The most numerous phytophagous insects damaging soybeans belonged to the Hemiptera order (34 out of 101 species of phytophages). The Lepidoptera order in the soybean agrocenosis was represented by 28 species (13.4% of the total fauna and 28.0% of the destructive fauna). Full article

Plants are directly exposed to several biotic factors. Among these, mite species belonging to the superfamilies Eriophyoidea and Tetranychoidea stand out due to their ability to injure or even transmit viruses to their host plants. In response to infestations by these organisms, reactive oxygen species (ROS), regulated by enzymatic and non-enzymatic antioxidants (homeostasis), can act as signaling molecules to induce defenses or even acclimatization in attacked plants. However, depending on the severity of the stress, there can be an imbalance between ROS and antioxidants that can result in oxidative stress, leading to membrane damage by lipid peroxidation, organelle inactivation, and even cell death. In this review, we outline for the first time the current state of understanding regarding the role of cellular processes in ROS metabolism, such as signaling, the potential damage induced by ROS, and the defense role of enzymatic antioxidant systems involved in the plant–mite relationship. Furthermore, we identify several gaps between redox metabolism and plant defense against phytophagous mites. Full article

Amblyseius swirskii are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. Tetranychus urticae is a global mite that is difficult to manage because of its high population growth rates, necessitating alternative management measures like biological control. Regarding the functional response, the effects of temperature and prey density are some of the essential behaviors of natural enemies. This study investigates the effect of varying temperatures and prey densities on A. swirskii, a biological control agent for T. urticae. The present results demonstrated the change in the functional response estimates when A. swirskii was reared at various temperatures and different prey densities. The results of the estimates regarding the searching efficiency (a′) showed the highest value (a′ = 0.919) at 26 °C and the lowest value (a′ = 0.751) at 14 °C. The handling time per prey item (T_h) for the predatory mites changed with the temperature and prey density, showing the shortest handling time at 26 °C (T_h = 0.005) and the highest value at 14 °C (T_h = 0.015). The functional response curves matched the type II functional response model, demonstrating the inverse dependence of temperatures and prey density with a positive quadratic coefficient. The predation curves for A. swirskii showed a significant difference between the mean numbers of T. urticae consumed at various prey densities and temperatures, illustrating a relationship between A. swirskii and T. urticae. Therefore, the results of this research may be utilized to forecast the behavior of A. swirskii and its usefulness in controlling T. urticae populations. Full article

Tetranychus urticae Koch, a phytophagous mite, is one of the most significant crop pests globally. The primary method employed for controlling T. urticae involves chemical means, utilizing synthesized products, posing the risk of developing resistance. The urgency for novel strategies integrated into pest management programs to combat this mite is becoming increasingly imperative. Botanical pesticides emerge as a promising tool to forestall arthropod resistance. Among these, extracts from Rutaceae plants, abundant in bioactive specialized metabolites, have demonstrated potential as insecticides and miticides. In this study, various concentrations of alkaloidal extracts sourced from the bark of Zanthoxylum schreberi J.F.Gmel. (Rutaceae) were evaluated against T. urticae adult females. Furthermore, the extract’s combination with three distinct commercial acaricides (i.e., chlorfenapyr, cyflumetofen, and abamectin) was also assessed for this mite. Chemical characterization of the extract via LC-MS allowed for the annotation of various compounds related to ten benzylisoquinoline-derived alkaloids. The extract, both alone and in combination with commercial insecticides, yielded varying responses, inducing over 40% mortality at 2% w/w, demonstrating a 90% repellency rate at the same concentration, and exerting a moderate impact on fecundity. These treatments extended beyond phenotypic responses, delving into the biochemical effects on treated T. urticae females through an exploration of the impact on four enzymes, i.e., acetylcholinesterase (AChE), glutathione S-transferase (GST), esterases (GE), and P450-like monooxygenases (PMO). Employing consensus docking studies and in vitro enzymatic evaluations, it was discovered that the Z. schreberi-derived extract and its constituents significantly affected two key enzymes, AChE and GST (IC₅₀ < 6 µM), which were associated with the phenotypic observations of T. urticae females. The evaluation of alkaloid-rich botanicals showcases promising potential as a relevant biotechnological strategy in addressing mite-related concerns, offering a pathway toward innovative and sustainable pest management solutions. Full article

Gall mites (Eriophyoidea) are cosmopolitan microscopic phytoparasites that often transmit viruses and induce gallogenesis. The tribe Calacarini is diagnosed by a set of plesiomorphic and homoplastic traits, including elimination of setae sc shared with other lineages of Eriophyoidea. We reviewed data on the generic diversity of calacarines, revised the concept of the type genus Calacarus Keifer 1940, and proposed three zones (MZ, SMZ, LZ) in the prodorsal shields of calacarines to simplify descriptions of their shield patterns. We describe three new calacarine species (Calacarus baviensisn. sp., C. burchelliaen. sp., and Viginticus searsiaen. sp.) from indigenous dicotyledonous trees from South Africa and Vietnam and report on new findings of Paracalacarus podocarpi Keifer in Brazil, Jiangsuacarus sp. in the USA, and Calacarus pusillus Pye in Latvia and Russia. The latter represents the new most northern locality of Calacarini. Reinvestigating the type species of Jaranasia Chandrapatya & Boczek 2000 revealed that absence of setae l’’ II is the only character separating it from Jiangsuacarus Xue 2009. We proposed two new combinations: Jiangsuacarus sesleriae (Skoracka 2004) n. comb. (transferred from Jaranasia) and Procalacarus mussaendae (Keifer 1977) n. comb. (transferred from Calacarus). Partial sequences of Cox1 and 28S genes were obtained for six calacarines, some of them originating from old ethanol material kept at room temperature. Molecular phylogenetics revealed a stable cluster of “true” calacarine sequences comprising Calacarus, Jaranasia, Latitudo, and Viginticus and a polyphyletic group of erroneous sequences assigned to Calacarini in GenBank. All investigated females of calacarines have a pair of genital tubules associated with the vestibulum and hypothesized to participate in fertilization. This finding may contribute to resolving the question on how the fusion of gametes happens in gall mites. Full article