Tetranychus Urticae Research Articles

Contrasting plant transcriptome responses between a pierce-sucking and a chewing herbivore go beyond the infestation site

BackgroundPlants have acquired a repertoire of mechanisms to combat biotic stressors, which may vary depending on the feeding strategies of herbivores and the plant species. Hormonal regulation crucially modulates this malleable defense response. Jasmonic acid (JA) and salicylic acid (SA) stand out as pivotal regulators of defense, while other hormones like abscisic acid (ABA), ethylene (ET), gibberellic acid (GA) or auxin also play a role in modulating plant-pest interactions. The plant defense response has been described to elicit effects in distal tissues, whereby aboveground herbivory can influence belowground response, and vice versa. This impact on distal tissues may be contingent upon the feeding guild, even affecting both the recovery of infested tissues and those that have not suffered active infestation.ResultsTo study how phytophagous with distinct feeding strategies may differently trigger the plant defense response during and after infestation in both infested and distal tissues, Arabidopsis thaliana L. rosettes were infested separately with the chewing herbivore Pieris brassicae L. and the piercing-sucker Tetranychus urticae Koch. Moderate infestation conditions were selected for both pests, though no quantitative control of damage levels was carried out. Feeding mode did distinctly influence the transcriptomic response of the plant under these conditions. Though overall affected processes were similar under either infestation, their magnitude differed significantly. Plants infested with P. brassicae exhibited a short-term response, involving stress-related genes, JA and ABA regulation and suppressing growth-related genes. In contrast, T. urticae elicited a longer transcriptomic response in plants, albeit with a lower degree of differential expression, in particular influencing SA regulation. These distinct defense responses transcended beyond infestation and through the roots, where hormonal response, flavonoid regulation or cell wall reorganization were differentially affected.ConclusionThese outcomes confirm that the existent divergent transcriptomic responses elicited by herbivores employing distinct feeding strategies possess the capacity to extend beyond infestation and even affect tissues that have not been directly infested. This remarks the importance of considering the entire plant’s response to localized biotic stresses.

Arthropods and ultraviolet radiation: Survival, growth and development

Abstract Ultraviolet radiation (UVR) has positive and negative impacts on organisms and affects entire ecosystems. It is currently receiving attention because of the interactions of UVR with changes in climate that are likely to affect agriculture and food security. A review is provided on the effects of different types of UVR on the survival, development and reproduction of insects, collembolans and mites. The foci are on how UVR is used in pest control and how it affects arthropod coloration and distribution. Direct exposure to UV‐A, UV‐B and UV‐C delays development and reduces survival and host‐seeking ability of arthropods; immature stages are more sensitive than the adults. Increased exposure of crops to UVR has indirect effects on herbivory, and regions with high UVR levels may permit crop production in the absence of certain pest insect species. The Bunsen‐Roscoe law of reciprocity was upheld for Diaphorina citri and Tetranychus urticae under the range of irradiances and durations of exposure used in two studies, which showed that, for a constant dose, the effects of low irradiances of long durations were equivalent to those of higher irradiances of shorter durations. DNA damage caused by UV‐C and UV‐B can be repaired by photoreactivation; both white light and UV‐A are effective.

The RIN4-like/NOI proteins NOI10 and NOI11 modulate the response to biotic stresses mediated by RIN4 in Arabidopsis

Key messageNOI10 and NOI11 are two RIN4-like/NOI proteins that participate in the immune response of the Arabidopsis plant and affect the RIN4-regulated mechanisms involving the R-proteins RPM1 and RPS2.The immune response in plants depends on the regulation of signaling pathways triggered by pathogens and herbivores. RIN4, a protein of the RIN4-like/NOI family, is considered to be a central immune signal in the interactions of plants and pathogens. In Arabidopsis thaliana, four of the 15 members of the RIN4-like/NOI family (NOI3, NOI5, NOI10, and NOI11) were induced in response to the plant herbivore Tetranychus urticae. While overexpressing NOI10 and NOI11 plants did not affect mite performance, opposite callose accumulation patterns were observed when compared to RIN4 overexpressing plants. In vitro and in vivo analyses demonstrated the interaction of NOI10 and NOI11 with the RIN4 interactors RPM1, RPS2, and RIPK, suggesting a role in the context of the RIN4-regulated immune response. Transient expression experiments in Nicotiana benthamiana evidenced that NOI10 and NOI11 differed from RIN4 in their functionality. Furthermore, overexpressing NOI10 and NOI11 plants had significant differences in susceptibility with WT and overexpressing RIN4 plants when challenged with Pseudomonas syringae bacteria expressing the AvrRpt2 or the AvrRpm1 effectors. These results demonstrate the participation of NOI10 and NOI11 in the RIN4-mediated pathway. Whereas RIN4 is considered a guardee protein, NOI10 and NOI11 could act as decoys to modulate the concerted activity of effectors and R-proteins.

Development and reproduction of four predatory mites (Parasitiformes: Phytoseiidae) feeding on the spider mites Tetranychus evansi and T. urticae (Trombidiformes: Tetranychidae) and the dried fruit mite Carpoglyphus lactis (Sarcoptiformes: Carpoglyphidae)

The tomato red spider mite, Tetranychus evansi, a notorious crop pest, invaded New Zealand in 2020. In an effort to identify potential biological control agents for this species, we investigated the capabilities of four phytoseiid predators found in New Zealand—Amblyseius herbicolus, Amblyseius lentiginosus, Amblydromalus limonicus, and Neoseiulus californicus. For comparison, we also used the two-spotted spider mite, T. urticae, and the dried fruit mite, Carpoglyphus lactis, as prey for these predators. In our first experiment we monitored immature development and oviposition rate (over the first 5 days) of the phytoseiid predators when presented with the three prey species. While all four species of predators could develop and reproduce on the factitious (alternative and easily available) prey species C. lactis, they had limited success when feeding on T. evansi and T. urticae. Amblyseius herbicolus, A. lentiginosus, and Amblyd. limonicus were unable to reach adulthood when feeding on T. evansi and T. urticae in the presence of the protective webbing spun by the mites. While N. californicus matured when exposed to T. evansi reared on black nightshade leaves, it did not lay eggs—indicating potential limitations in prey suitability. In our second experiment, gravid females of all four predators failed to maintain their reproduction when provided with T. evansi in the presence of webbing. Neoseiulus californicus exhibited phenotypic plasticity in its developmental time, body size, and oviposition rate when feeding on the three prey species. This suggests that N. californicus has the flexibility to switch diets to survive during food scarcity, especially when their primary prey, T. urticae, is limited. This study is also the first to offer life history information about A. lentiginosus. Our findings underscore the difficulties of controlling T. evansi using phytoseiid predators and highlight the need for diversified pest management strategies, including the use of alternative insect predators or entomopathogenic fungi.

Integrating museum collections and molecules reveals genus-level synonymy and new species in red devil spiders (Araneae, Dysderidae) from the Middle East and Central Asia

This paper reviews little-known species of the dysderid spider genera Dysdera Latreille, 1804, and Dysderella Dunin, 1992 based on specimens collected in the Caucasus, Middle East, and Central Asia. After combining molecular phylogeny of five mitochondrial and three nuclear genes with morphological evidence, Dysderella is proposed as a junior synonym of Dysdera. In addition, three species are described as new to science: D. jaegeri Bellvert & Dimitrov sp. nov., D. naouelae Bellvert & Dimitrov sp. nov., and D. kourosh Bellvert, Zamani & Dimitrov sp. nov. Four combinations are proposed: Dysdera caspica Dunin, 1990 comb. rev., Dysdera transcaspica Dunin & Fet, 1985 comb. rev., Dysdera elburzica (Zamani, Marusik & Szűts, 2023) comb. nov. and Dysdera sancticedri (Brignoli, 1978) comb. nov. (ex. Dasumia Thorell, 1875). Furthermore, we report a first record of D. festai Caporiacco, 1929 in Turkey and its male cheliceral polymorphism. Our results illustrate the deficiencies that undermine the current taxonomy of this genus. For example, many species are described based on only one or few specimens or limited locality data. The advancements in DNA sequencing technologies applied to museum specimens reduce the need for fieldwork collection and export of fresh specimens. This highlights the significance of museum collections for improving research in this field.

Emerging Insect Pests of Vegetable Crops under Changing Climate Scenario

Crop losses in vegetables vary greatly depending on plant variety, cropping season, geographical location, and pest damage potential. Vegetable crops are heavily impacted by insect pests and diseases due to their softness, fragility and short duration in comparison to other crops. An emerging insect pest is one that has been observed in a specific crop-infested area and has progressively increased in population over time. Emerging insect pests have the potential to cause economic harm. In other words, an emerging insect pest is a pest insect whose position has shifted from minor to major or secondary to primary pest. The number of existing minor pests is increasing, as is the arrival of new ones, such as mealybugs, fruit flies, stem borers, diamondback moths among phytophagous insects and red spider mites among acarine. Recent infestations, such as South American tomato pinworm and chili black flower thrips, have caused serious damage to tomato and chili harvests. This review envisages on the variables that contribute to the establishment of new invasive pests, the persistence of main pests, general pest management practices, and integrated pest management to achieve sustainable vegetable production.

Comparative Bio-efficacy of Different Acaricides on the Population of Two-spotted Spider Mites in Apple Trees

Comparative Bio-efficacy of Different Acaricides on the Population of Two-spotted Spider Mites in Apple Trees

Measurement of Fitness and Predatory Ability of Four Predatory Mite Species in Tibetan Plateau under Laboratory Conditions.

Predatory mites are biological control agents used in many countries against various vegetable pests, particularly spider mites. Despite the significant presence of predatory mites in the Tibetan plateau, there is limited research on their potential against spider mites in the area. This study investigated the fitness parameters and performance against TSSM of four predatory, including Amblyseius swirskii (Athias-Henriot) and three species from the genus Neoseiulus (Neoseiulus californicus (McGregor), Neoseiulus barkeri (Hughes), and Neoseiulus cucumeris (Oudemans)), originally collected from fields in the Tibetan Plateau. Compared to the other three predatory species, A. swirskii exhibited the highest fecundity (11.60 ± 0.34) and the highest pre-adult survival rate (83.33 ± 3.33%). Since their juvenile survival rate (SR) was extremely low (13.33% ± 5.77%), most N. barkeri nymphs died before emergence. Compared to the other three predatory mites, A. swirskii showed the highest predation capacity against adult TSSMs at 15 d post-release (14.28 ± 2.24). Based on the results, A. swirskii was the most effective, and N. barkeri was the least effective in controlling two-spotted mites in the Tibetan Plateau among the four species tested in this study. Collectively, these findings imply notable advantages in employing A. swirskii for controlling two-spotted mites in the Tibetan Plateau. This study informs the development of a feasible biological control method based on suitable predatory mite species to manage TSSMs in the Tibetan Plateau.

Design, synthesis, and pesticidal activities of novel pyrimidin‐4‐amine derivatives containing trifluoroethyl sulfide moiety

AbstractIn order to overcome the problem of pesticide resistance, it is necessary to discover novel pesticides with new mechanisms of action. Herein, a series of novel pyrimidin‐4‐amine derivatives containing trifluoroethyl sulfide moiety were designed and synthesized. Bioassays indicated that the title compounds synthesized possessed excellent acaricidal activity against Tetranychus urticae and fungicidal activity against Erysiphe graminis and Puccinia sorghi. Especially, the acaricidal activity of 5‐chloro‐6‐(difluoromethyl)‐N‐(2‐(2‐fluoro‐4‐methyl‐5‐((2,2,2‐trifluoroethyl)thio)phenoxy)ethyl)pyrimidin‐4‐amine (compound T4, LC50 = 0.19 mg/L) against T. urticae was close to commercial acaricide cyenopyrafen, and the fungicidal activity of 5‐chloro‐6‐(difluoromethyl)‐2‐methyl‐N‐(2‐(3‐((2,2,2‐trifluoroethyl)thio)phenoxy)ethyl)pyrimidin‐4‐amine (compound T15, EC50 = 1.32 mg/L) against P. sorghi. was superior to commercial fungicide tebuconazole. The synthesis and characterization of these compounds were given and the structure–activity relationships were discussed.

Tomato pest recognition using convolutional neural network in Bangladesh

The tomato is one of the most popular and well-liked veggies among Asians. It is interesting to note that in Bangladesh, it is the second most significant vegetable consumed. Moreover, tomato is served not only as a vegetable, but it is also served as sauce, jam, etc., and used in making different types of cuisines. But the fact is due to the pests, thousands of tons of tomatoes are harmed every year in Bangladesh. The production of tomatoes in Bangladesh is harmed by a number of dangerous pests. We develop a solution to recognize pests at an early stage. Five different pest types, including aphids, red spider mites, whiteflies, looper caterpillars, and thrips, have been studied in this research. To identify tomato pests, we curated image datasets from online and offline repositories and processed them using a convolutional neural network (CNN) model. We used features from CNN layers for three machine learning algorithms: Random Forest (RF), support vector machine (SVM), and K-Nearest Neighbors (K-NN). This comprehensive approach allowed a thorough comparison of these algorithms in tomato pest recognition. For recognizing tomato pests, our methods generate excellent results. The accuracy of our experiment is 95.49% which indicates the successful completion of the experiment.

Resistance of oil palm seedlings against red spider mite attack through boron fertilizer application

Resistance of oil palm seedlings against red spider mite attack through boron fertilizer application

Rearing Neoseiulus cucumeris and Amblyseius swirskii (Mesostigmata: Phytoseiidae) on non-target species reduces their predation efficacy on target species

Abstract In Florida, strawberries are prone to infestation by Tetranychus urticae Koch (twospotted spider mite; Trombidiformes: Tetranychidae) and Scirtothrips dorsalis Hood (chilli thrips; Thysanoptera: Thripidae). Management of these pests using conventional insecticides is becoming difficult, thereby forcing many growers to adopt the use of commercially available biological control agents including Neoseiulus cucumeris Oudemans and Amblyseius swirskii Athias-Henriot (both Mesostigmata: Phytoseiidae). These predators are mass reared on prey different from T. urticae, and their prey switching capacity is unknown. Therefore, the objective of this study was to compare the predation capacity of A. swirskii and N. cucumeris feeding on familiar and unfamiliar prey. Thus, using T. urticae as a non-familiar prey model organism, a no choice test was conducted where A. swirskii and N. cucumeris were each provided with Acarus spp. (commonly used as prey for commercial rearing of predatory mites) as familiar prey and eggs, deutonymphs, and adult females of T. urticae as unfamiliar prey. Prey consumption was recorded at 12, 24, 36 and 48 h. Our results show that both A. swirskii and N. cucumeris exhibited higher prey consumption when prey was familiar (Acarus spp.) compared to unfamiliar prey. Additionally, both predators showed higher consumption of eggs compared to T. urticae nymphs and adults. In 12 h, both predators had consumed 50 % of eggs, however, 36–48 h were required for 50 % of the T. urticae adults and nymphs to be consumed. Therefore, strawberry growers utilizing these predatory mites ought to refrain from the use of insecticides known to be detrimental to predatory mites for a period of at least 48 h to allow the predators to adjust to the new prey and environment.

Toxic, Repellent, and Oviposition-Inhibiting Effects of Almina Diatomaceous Earth on Tetranychus urticae Koch, 1836 (Acari: Tetranychidae)

Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is one of the most important pests of agricultural fields worldwide. This study was carried out using the leaf disc method to determine whether local diatomaceous earth (Almina) has a toxic, repellent, and oviposition-inhibiting effect on T. urticae. Adult females of T. urticae were placed on leaf discs immersed in 10%, 5%, 2.5%, and 1.25% concentrations (w/v) of diatomaceous earth. Considering the mortality rates after 24, 48, 72, and 96 hours, respectively, the highest mortality rate was determined as 33.56% at 10% concentration. At the same concentrations, the highest repellent effects were found to be 64.54%, 42.10%, 20.35%, and 19.46% after 1 hour, respectively. Although the number of eggs laid by females increased over time at all concentrations, it was statistically less than the control at 10% and 5% concentrations. In light of the data obtained from this study, further studies are planned to increase the effectiveness of Almina diatomaceous earth by mixing it with botanical extracts or entomopathogens in the control of T. urticae.

Microbial biorationals as an effective alternative to pesticides for control of two spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) on parthenocarpic cucumber grown under protected conditions

Microbial biorationals as an effective alternative to pesticides for control of two spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) on parthenocarpic cucumber grown under protected conditions

First record of the tomato red spider mite, Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae) in Mexico, from cultivated and wild solanaceous plants

The tomato red spider mite Tetranychus evansi Baker and Pritchard is a pest of primary importance on cultivated Solanaceae in some countries. Based on morphological characters and sequencing of a fragment of the cytochrome oxidase subunit I (COI) of mitochondrial DNA (mtDNA), the presence of T. evansi is reported for the first time in Mexico, from four municipalities (counties) in three states: Baja California, Nuevo León and Tamaulipas, on solanaceous plants, both cultivated (tomato, Solanum lycopersicum L., and potato Solanum tuberosum L.) and wild (nigthshades, Solanum cf. americanum Mill. and Solanum nigrescens Mart. and Gal.). The molecular study confirms for the first time the presence of haplotype 4 (belonging to clade I) of T. evansi in North America (Nuevo Leon state). This clade includes most invasive T. evansi populations worldwide. Although no studies have been carried out on the economic impact of T. evansi in Mexico, it is of utmost importance to recognize the presence of this species to establish sound management strategies.

Demography and Population Projection of Tetranychus urticae (Tetranychidae) on Phaseolus vulgaris (Fabaceae) Colonized by Entomopathogenic Fungal Endophytes.

Tetranychus urticae is a highly polyphagous and global pest. Spider mites primarily feed on the underside of leaves, resulting in decreased photosynthesis, nutritional loss, and the development of chlorotic patches. We investigated the life tables of the two-spotted spider mite T. urticae on fungal endophyte Beauveria bassiana colonized and untreated plants of the common Phaseolus vulgaris L., a bean plant. Based on the age-stage, two-sex life table theory, data were evaluated. The mites raised on untreated plants had protonymphs, deutonymphs, and total pre-adult stage durations that were considerably shorter (1.76, 2.14, and 9.77 d, respectively) than the mites raised on plants that had been colonized (2.02, 2.45, and 10.49 d, respectively). The fecundity (F) varied from 28.01 eggs per female of colonized plants to 57.67 eggs per female of endophyte-untreated plants. The net reproductive rate (R0) in the plants with and without endophytes was 19.26 and 42.53 brood, respectively. The untreated plants had an intrinsic rate of increase (rm) of 0.245 days as opposed to the colonized plants, which had an r of 0.196 days and a finite rate of increase (λ) (1.27 and 1.21, respectively). Population forecasts based on a two-sex, age-stage life table demonstrated the dynamism and variability of the stage structure. Furthermore, the colonization of B. bassiana had a negative impact on the growth and development of T. urticae. It lowered the adult mite life span, female fecundity, net reproduction rate, and intrinsic growth rate. We propose that future research should better use entomopathogenic fungal endophytes to understand host plant resistance strategies in integrated pest management.

Integration of the Generalist Predator Nabis americoferus (Hemiptera: Nabidae) in a Greenhouse Strawberry Biocontrol Program with Phytoseiid Predatory Mites and the Entomopathogenic Fungus Beauveria bassiana.

In strawberry production, western flower thrips (WFT) and two-spotted spider mites (TSSM) inflict feeding damage and reduce the yield. Biological control for these pests often includes phytoseiid predatory mites and entomopathogenic fungi. The hemipteran family Nabidae have been reported as prominent predators in open-field strawberry. Nabis americoferus Carayon is a new biocontrol agent developed in Canada. This study examined if this species was a good candidate for integration with biological control for greenhouse strawberry production. The laboratory trials showed that Phytoseiulus persimilis Athias-Henriot and Amblyseius swirskii Athias-Henriot were compatible with N. americoferus, especially when alternative food was available. In contrast, the nabid was not compatible with the Beauveria bassiana (Balsamo) GHA strain. A greenhouse cage study was conducted to determine if it was beneficial to add N. americoferus to the phytoseiid-mites-based biological control program for WFT and TSSM in greenhouse strawberry. The release of N. americoferus on a banker plant together with the placement of sachets of Neoseiulus cucumeris (Oudemans) and Neoseiulus californicus (McGregor) was beneficial, not only potentially reducing the number of sachet applications, but also providing better pest control than phytoseiid mites alone. Neither the phytoseiids nor the N. americoferus numbers were significantly affected by the presence of each other.

New infestation records of two-spotted spider mites on potato tubers under storage conditions and response of genotypes at Kulumsa, Ethiopia

The study sought to ascertain spider mite prevalence, infestation, and identification and to assess the response of potato genotypes. In 2022, this pest was only observed on some genotypes in December. In late January, an infestation, incidence, and severity increased from 10 to 13 genotypes on potato tuber stocks stored for irrigation experiments. Those genotypes were planted in irrigated fields, and the sprouted tuber losses ranged from 12.5% to 100% and up to 15.38% in the 2022 and 2023 records, respectively. Following this, spider mites, often known as two-spotted spider mites (TSSM) or Tetranychus urticae, were identified. This is the first time a potato sprout infestation has been recorded in Ethiopia. The two-spotted spider mites damaged the tubers quantitatively by sucking the moisture of sprouts up to the 5th grade, with 97 and >75% infestation levels, incidence, and severity, respectively. The pest grows very rapidly and hastens the drying of sprouted tuber leaves. Some genotypes were resistant to TSSM and recovered after the sprouts were infected and dried, which were treated with pesticides in 2023. The typical agricultural insecticides were ineffective in controlling the pest in the first year, and a Profenofos was applied in the second year. Thus, seed tubers are the main production limit unless appropriate research efforts are undertaken and management techniques are created. Int. J. Agril. Res. Innov. Tech. 13(2): 55-63, Dec 2023

Production of biopesticide from Melia azedarach Linn extract obtained by supercritical fluid extraction for the control of Tetranychus urticae

Compounds derived from plant extracts, such as those from the fruits and leaves of Melia azedarach Linn (chinaberry tree), which contain azadirachtin, have been utilized for crop pest control. However, these natural compounds are susceptible to degradation during extraction and in field conditions. To address this, extraction processes involving supercritical fluid and microencapsulation via spray drying may be employed to obtain and preserve biopesticidal molecules. This study focuses on producing a biopesticide from M. azedarach L. fruit extract using supercritical CO2, and microencapsulation via spray drying with a blend of cheese whey and gum Arabic. The extract was obtained from chinaberry fruits rich in azadirachtin (736.92 μg/L) using supercritical CO2 at 250 bar and 50 °C for 120 min, with a yield of 3.44%. The extract was then encapsulated using cheese whey and gum Arabic (70:30) as encapsulating agents at extract:encapsulating agents ratios of 1:10 and 1:15. Mortality rates of Tetranychus urticae Koch adult females and their eggs, in contact and residual assays with both non-encapsulated and encapsulated extract, did not significantly differ (p > 0.05) from the commercial acaricide abamectin. This study introduces a potential new biopesticide that utilizes chinaberry extract obtained through supercritical CO2 extraction and encapsulation for industrial scale-up studies, and this approach holds promise for the production of an effective biopesticide for crops affected by two-spotted spider mites.

Developmental biology and impact on yield loss by two-spotted spider mite, (Tetranychus urticae) in brinjal crop

Developmental biology and impact on yield loss by two-spotted spider mite, (Tetranychus urticae) in brinjal crop