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The common bed bug, Cimex lectularius L., is a difficult urban pest to control. A simulated field study was conducted to compare the efficacy of steam application and an insecticide mixture spray (0.05% acetamiprid and 0.06% bifenthrin mixture) against C. lectularius. Three types of furniture (desk chair, upholstered armchair, and wooden table) were treated in the laboratory. The efficacy of the treatments was evaluated by visual inspection and placement of interceptor traps under the legs of the furniture. One hundred mixed stages of an insecticide-resistant population of C. lectularius were released onto each furniture item. After a 10-day acclimation period, each furniture item received steam treatment, insecticide spray, or no treatment. The second application of treatment was conducted 14 d later. Bed bug counts from interceptors and visual inspections were recorded at 13 d and 28 d after the initial treatment. At 28 d, the mean (± SE) live bed bug count in the steam, spray, and control group was 1 ± 0, 2 ± 1, and 83 ± 10, respectively. Both treatment methods were highly effective in controlling bed bugs on furniture. The mean bed bug count from interceptors in the steam, spray, and control groups were 0.3 ± 0.2, 11 ± 7, and 47 ± 9, respectively. There was no significant difference in the efficacy between steam and spray treatments based on either visual inspection or bed bug counts from interceptors. However, based on interceptor counts, the steam treatment caused faster bed bug population reduction than insecticide sprays., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Models validation in QSAR, pharmacophore, docking and others can ensure the accuracy and reliability of future predictions in design and selection of molecules with biological activity. In this study, pyriproxyfen was used as a pivot/template to search the database of the Maybridge Database for potential inhibitors of the enzymes acetylcholinesterase and juvenile hormone as well. The initial virtual screening based on the 3D shape resulted in 2000 molecules with Tanimoto index ranging from 0.58 to 0.88. A new reclassification was performed on the overlapping of positive and negative charges, which resulted in 100 molecules with Tanimoto's electrostatic score ranging from 0.627 to 0.87. Using parameters related to absorption, distribution, metabolism and excretion and the pivot molecule, the molecules selected in the previous stage were evaluated regarding these criteria, and 21 were then selected. The pharmacokinetic and toxicological properties were considered and for 12 molecules, the DEREK software not fired any alert of toxicity, which were thus considered satisfactory for prediction of biological activity using the Web server PASS. In the molecular docking with insect acetylcholinesterase, the Maybridge3_002654 molecule had binding affinity of -11.1 kcal/mol, whereas in human acetylcholinesterase, the Maybridge4_001571molecule show in silico affinity of -10.2 kcal/mol, and in the juvenile hormone, the molecule MCULE-8839595892 show in silico affinity value of -11.6 kcal/mol. Subsequent long-trajectory molecular dynamics studies indicated considerable stability of the novel molecules compared to the controls.AbbreviationsQSARquantitative structure-activity relationshipsPASSprediction of activity spectra for substancesCommunicated by Ramaswamy H. Sarma.

Copidosoma truncatellum (Hymenoptera: Encyrtidae) is an important parasitoid wasp of the soybean looper, Chrysodeixis includens, but its effectiveness can be severely curtailed by the application of certain insecticides. Therefore, to identify insecticides that are potentially compatible with C. truncatellum, the lethal and behavioral effects of nine chemicals used to control the soybean looper were evaluated for their toxicity to the wasp. Chlorantraniliprole, chlorfenapyr, flubendiamide, and indoxacarb were the least toxic insecticides to the parasitoid, resulting in mortalities of less than 25%. In contrast, cartap, deltamethrin, and methomyl caused 100% mortality, and acephate and spinosad caused 76% and 78% mortality, respectively. At least one of the detoxifying enzymes (monooxygenase, glutathione S-transferase, and/or esterases) may be involved in the mechanisms underlying the selectivity of chlorantraniliprole, chlorfenapyr, flubendiamide, and indoxacarb for the parasitoid based on the results for the insecticide plus synergist treatment. Changes in the behavioral patterns (walking time and resting time) of the parasitoid were found with exposure to acephate, flubendiamide, indoxacarb and methomyl, but behavioral avoidance was not observed. Our results indicate that the insecticides chlorantraniliprole and chlorfenapyr are the most suitable for inclusion in integrated pest management strategies for the control of C. includens., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

There is increasing demand for new products for vegetable pest management. Thus, the aim of this study was to assess the toxicity of pyrethroids with acid moiety modifications to measure the insecticidal activity of these compounds on the lepidopteran vegetable pests Diaphania hyalinata (L.) (Lepidoptera: Pyralidae) and Asciamonuste (Latreille) (Lepidoptera: Pieridae) and evaluate their selectivity for the predatory ant Solenopsis saevissima (F. Smith) (Hymenoptera: Formicidae) and pollinator Tetragonisca angustula (Latreille) (Hymenoptera: Apidae: Meliponinae). Racemic mixtures of five new pyrethroids (30 µg molecule mg -1 insect body weight) resulted in high (100%) and rapid (stable LD 50 after 12 h) mortality in D. hyalinata and A. monuste. In A. monuste, the trans-pyrethroid [12] isomer showed similar toxicity to permethrin. For D. hyalinata, the trans-pyrethroid [9] isomer and cis-pyrethroid [10] isomer were as toxic as permethrin. Due to their low selectivity, these new pyrethroids should be applied on the basis of ecological selectivity principles to minimize impacts on nontarget organisms S. saevissima and T. angustula.

Background: The effectiveness of a biological control agent depends on how well it can control pests and how compatible it is with pesticides. Therefore, we reported the multigenerational effect of a commonly used insecticide, imidacloprid, on the functional response of a widely acclaimed egg parasitoid, Trichogramma chilonis Ishii, to different densities of the host Corcyra cephalonica Stainton eggs. The study investigated the outcomes of the median lethal concentration (LC 50 ) and sublethal concentrations (LC 5 , LC 30 ), along with control treatments for five continuous generations (F 1 to F 5 )., Results: The results showed that the F 5 generation of LC 30 , both of the F 1 and F 5 generations of LC 50 , and the control all had a Type II functional response. A Type I functional response was exhibited for the F 1 generation of LC 30 and both generations of LC 5 . The attack rate on host eggs treated with LC 5 and LC 30 did not change (decrease) with the shift in the type of functional response as compared to the control. A significant increase in the searching efficiency (a) was observed in the later generation (F 5 ) under the exposure of LC 5 and LC 30 imidacloprid concentrations. A lower handling time (T h ) in both generations of the LC 5 followed by LC 30 treated individuals was observed when compared with the control and LC 50 treatments. The per capita parasitization efficiency (1/T h ) and the rate of parasitization per handling time (a/T h ) were also considerably higher in both the generations of LC 5 and LC 30 than in the control and LC 50 , thereby implying positive effects of imidacloprid on the parasitization potential of T. chilonis., Conclusion: Altogether, these multigenerational outcomes on the functional response of T. chilonis could be leveraged to control the intractable lepidopteran pests under the mild exposure of imidacloprid in integrated pest management (IPM) programs as well as in the mass rearing of the parasitoid, T. chilonis. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Endophytic fungi are microorganisms capable of colonizing the interior of plant tissues without causing damage to them. The study of the secondary metabolites produced by their vast biodiversity fungal is relevant for the discovery of new products for biotechnological and agrochemical applications. In addition, extract of the endophytic fungus Aspergillus sp., isolated from the almonds of Bertholletia excelsa Humn & Bonlp collected in the Brazilian Amazon, oviposition deterrent, and larvicidal activity of against Aedes aegypti. In the oviposition deterrence test was observed that females able to lay eggs preferred the control oviposition sites (46.6%). Furthermore, the extract showed larvicidal activity with LC50 26.86 µg/mL at 24 h and 18.75 µg/mL at 48 h. Molecular docking studies showed the compound Aspergillol B a potent larvicide by to inhibit the acetylcholinesterase enzyme (- 7.74 kcal/mol). These results indicate that compounds from secondary metabolites of Aspergillus sp., isolated from almonds of B. excelsa, are useful biological potential against vectors A. aegypti., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Stingless bees have been recognized as essential plant pollinators and producers of various natural products in neotropical areas. Research into the potential risks of pesticides they may be exposed to in agricultural fields, however, remains meagre. Especially the toxicity of pesticide mixtures likely to occur under real-world conditions and that are likely to exert synergetic effects has been poorly studied. The aim of the present study was therefore to evaluate the single and mixture acute contact and oral toxicity of commercial products containing the insecticide abamectin and the fungicide difenoconazole in laboratory bioassays with the Brazilian native stingless bee Melipona scutellaris. In addition, a comparison of the insecticide sensitivity of stingless bees relative to the honeybee Apis mellifera was made based on previously published toxicity data. Except for oral exposure to abamectin, M. scutellaris appeared to be more sensitive that A. mellifera in the single compound toxicity tests. A difenoconazole concentration at the NOEC (no observed effect concentration) level indicated a synergetic toxic interaction with abamectin. A sensitivity comparison based on published toxicity data for A. mellifera and stingless bees indicated several insecticidal modes of action having a high relative sensitivity to stingless bees that need especial consideration in future studies. The research findings highlight the need for testing native bee species and environmentally relevant pesticide mixtures in risk assessments to avoid underestimation of potential risks to bee populations and the subsequent loss of pollination ecosystem services., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This work aimed to evaluate the residual action of five insecticides on larvae and adults of the predators Chrysoperla externa (Hagen) and Eriopis connexa (Germar). The insecticides gamma-cyhalothrin, imidacloprid+beta-cyfluthrin, methomyl, thiamethoxam, and thiamethoxam+lambda-cyhalothrin were sprayed in pod bean plants until the point of runoff. Weekly, at 3, 10, 17, 24, and 31 days, first instar larvae and adults of both predators were exposed to leaves containing dry residues of the insecticides. Based on the mortality observed throughout the bioassays, the insecticides were classified according to the scale of the residual effects proposed by the International Organization for Biological and Integrated Control (IOBC). Except for thiamethoxam+lambda-cyhalothrin, which was moderately persistent (class 3) to larvae of C. externa and E. connexa, all other tested insecticides were persistent (class 4) to larvae of both species. Gamma-cyhalothrin, imidacloprid + beta-cyfluthrin, and methomyl were persistent (class 4) to C. externa adults, while thiamethoxam was moderately persistent (class 3) and thiamethoxam + lambda-cyhalothrin was slightly persistent (class 2) to the adult stage. As for E. connexa adults, imidacloprid + beta-cyfluthrin and methomyl were persistent (class 4) and gamma-cyhalothrin, thiamethoxam, and thiamethoxam + lambda-cyhalothrin were moderately persistent (class 3). Thus, due to extended residual effect, these insecticides must be avoided when larvae and adults of both predators are active in the crop.

The use of insecticides on a large scale and applied at the wrong time can increase the cost of potato production. Good agricultural pest management practices can reduce the number of insecticide applications and promote the sustainability of potato production in modern agriculture. Thus, the objective was to compare the costs and revenues of a pest management system that uses monitoring (IPM-integrated pest management) with a conventional system (calendar-based insecticide application) in the potato crop. Two experiments were carried out: experiment 1, carried out in the summer with the cultivars Ágata, Atlantic, and FLs 2027, 1867, 2215, and 2221, and experiment 2, carried out in autumn with the cultivar Ágata. The densities of sucking insects, defoliators, and natural enemies were evaluated and compared. In both experiments, treatments were based on pest monitoring (insecticide applications when reaching economic thresholds [ETs]) and a conventional system (calendar-based insecticide application). In experiment 2, a control group was also carried out without the use of insecticides. In experiment 1, with the use of pest monitoring, the number of sprays was reduced by 66.67%, pest control costs were decreased by 60.86%, and there was an increase of 8.97% in net income from potato production. Whilst in experiment 2, the number of sprays was reduced by 71.42%, pest control costs were decreased by 51.38%, and an increase of 12.75% in net revenue from potato production was observed. Thus, it is concluded that the application of insecticides when the pest population reaches the economic threshold (ET) reduces insecticide applications and costs and increases net income in the potato crop. [ABSTRACT FROM AUTHOR]

Bees can be contaminated with pesticides in agricultural areas during foraging; however, effects of pesticides on stingless bee species are not well studies. Thus, this research evaluated the toxic effects of the insecticide chlorpyrifos, acaricide cyflumetofen and the fungicide difenoconazole for Tetragonisca angustula exposed in different means of exposure to pesticides under laboratory conditions. For this, pesticides were applied to bees through three modes of exposure: ingestion, treated surface and topical application based on the doses recommended by the manufacturers (chlorpyrifos—100 mL / 100 L of water; cyflumetofen—40 mL / 100 L of water; difenoconazole—20 mL / 100 L of water). After exposure, bees were evaluated within one to 96 h for survival and effects on behavior. In bees exposed to contaminated food up to 96 h of product exposure, survival was 0%, 96% and 76% respectively for chlorpyrifos, cyflumetofen and difenoconazole. In the treatment of contact with treated surfaces, bee survival was 0%, 100%, and 42%, whereas for topical application, survival rates were 0%, 88%, and 100% for the same pesticides. Regardless of the lethal effects of cyflumetofen and difenoconazole, the bees that survived showed significant behavioral changes, such as agitation, constant flapping and self-cleaning. Chlorpyrifos was extremely toxic to T. angustula in the three exposure means evaluated, whereas, bees exposed to difenoconazole were less tolerant when applied via ingestion and on treated surface. Cyflumetofen had a low effect on bee survival, however, all pesticides caused changes in the behavior of bees. [ABSTRACT FROM AUTHOR]

The use of medicinal plants is an ancient practice used by man to treat various ailments and is expanding throughout the world. The so-called neglected diseases, such as dengue, yellow fever, Zika, and chikungunya transmitted by the A. aegypti mosquito, have affected and killed thousands of people. In this sense, the inclusion of herbal medicines in the public health system would help improve the quality of primary care provided for the population and serve as an alternative for vector control. In this context, as an alternative for chemical control of natural origin, herbal medicines that have insecticidal, larvicidal, and repellent action appear. Therefore, the present work aims to carry out a survey of some recent works related to the Lamiaceae family with potential for the development of herbal medicines for the control of diseases transmitted by Aedes aegypti, with an emphasis on promising technological innovations with a repellent, insecticide and larvicide action mechanism. The article was developed through surveys of scientific and ethnobotanical information, using information from works published in Portuguese, English, and Spanish. The results proved the potential for the development of herbal medicines with a larvicidal, insecticidal, and repellent action mechanism for species belonging to the Lamiaceae family, presenting significant toxicity against insects, but negligible toxicity for animals, being easy to obtain, manipulate and apply, also presenting economic viability and non-cumulative effect on man and animals. The researches listed contribute to the feasibility of new biological tests that help in determining the most appropriate concentrations of phytoconstituents from extracts or essential oils that may be suitable for the formulation of repellents and other products for vector control. [ABSTRACT FROM AUTHOR]

The extensive use of insecticides can cause adverse side effects on pollinators, which negatively impact crop productivity. The pollination carried out by the honeybee Apis mellifera L. (Hymenoptera: Apidae) is crucial in increasing the productivity of the melon (Cucumis melo L.). The main objective of this study was to assess if insecticides applied in the cultivation of cantaloupe melon exhibit significant levels of toxicity toward A. mellifera. We tested the toxicity of azadirachtin, pyriproxyfen, chlorantraniliprole, and imidacloprid, which are commonly sprayed to manage melon pests such as the whitefly Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae), the pickleworm Diaphania nitidalis (Stoll) and the melonworm Diaphania hyalinata (L.) (Lepidoptera: Pyralidae). Three treatments were carried out, 0.0×, 0.1x and 1.0x the concentration recommended by the manufacturer for the control of those pests. Repellency tests, analysis of mortality through contact and ingestion, and flight tests were performed. The insecticide imidacloprid caused mortality rates above 90% in all tested exposure pathways, displaying high residue persistence on plants. Although not causing significant mortality in the ingestion test, pyriproxyfen caused significant mortality after exposure through contact, and change in flight ability. Azadirachtin caused mortality in the ingestion test and impaired the flight ability of bees, while chlorantraniliprole only impaired the flight ability. Moreover, bees were not repelled by these insecticides, suggesting that they may collect contaminated food in the field while foraging. Altogether, ecofriendly, alternative pest control options should be developed, as well as the adoption of more selective insecticides, in order to reduce the non-target effects on honeybees and guarantee their pollination services. [ABSTRACT FROM AUTHOR]

BACKGROUND Investigating the impact of pesticides on non-target organisms is essential for sustainable integrated pest management programs. We therefore assessed the toxicity of ten insecticides to the brassica caterpillar Ascia monuste and its ant predator Solenopsis saevissima and examined the effect that the insecticide synergists had on toxicity to the predator. We also assessed the residual period of control and impact of the insecticides during the brassica growing cycle. RESULTS All insecticides except flubendiamide exhibited mortality above the threshold required by Brazilian legislation (80%). Chlorantraniliprole, cyantraniliprole, indoxacarb and spinosad exhibited lower toxicity to the ant predator than they did to the brassica caterpillar. The results obtained for synergized insecticides suggest that selectivity to the predator was due the involvement of cytochrome P450-dependent monooxygenases. Chlorfenapyr and cyantraniliprole exhibited the highest residual periods of control to the brassica caterpillar, whereas malathion had the greatest impact on the predator. CONCLUSION Most of the insecticides efficiently controlled the brassica caterpillar, but not all exhibited selectivity to the predator. Therefore, due to the distinctive responses of organisms with respect to residual periods of control and the impact of the insecticides, spraying frequency must be strongly considered in integrated pest management programs. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]