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Euschistus heros (Fabricius) (Hemiptera: Pentatomidae) primarily attack the pods and seeds of soybean plants, causing severe economic losses in Neotropical Region, and chemical control is essential to avoid these losses. Thus, insecticides more effective against this pest and less toxic to Telenomus podisi Ashmead (Hymenoptera: Platygastridae) - the main biological control agent of E . heros - should be used. In this report, we studied the differential acute impacts of pesticides used in Brazilian soybean against E . heros and T . podisi and evaluated their sublethal effects on the parasitoid to identify effective pesticides towards the pest with less harmful effect to the natural enemy. The LC 50 of the insecticides to E . heros ranged from 1.20 to 533.74 ng a.i./cm 2 ; the order of toxicity was thiamethoxam + lambda-cyhalothrin > acetamiprid + fenpropathrin > zeta-cypermethrin > acephate > imidacloprid. All pesticides were classified as slightly to moderately toxic to T . podisi based on the risk quotient. The exposure of T . podisi females to imidacloprid and the insecticide pre-formulated mixtures reduced the emergence of the offspring parasitoids by up to 40% whereas zeta-cypermethrin and the insecticides pre-formulated mixtures reduced offspring survival. The preferred order of choice of insecticides for the management of E . heros according to agronomic, toxicological, and environmental feasibility was the following: thiamethoxam + lambda-cyhalothrin > zeta-cypermethrin > acetamiprid + fenpropathrin > acephate > imidacloprid. Our study provides important and pioneer information to select insecticides for effective control of E . heros with lower impacts on T . podisi .

Chrysoperla externa and Coleomegilla quadrifasciata are important biological control agents in peach orchards. However, orchard management with these predatory insects is viable only by using selective agrochemicals. The objective of this study is to evaluate the toxicity of nine agrochemicals used in peach orchards in larval and adult stages of the C. externa and C. quadrifasciata in laboratory conditions. The bioassays followed the methodologies proposed by the International Organization for Biological and Integrated Control (IOBC). Larvae and adults of C. externa and C. quadrifasciata were exposed to the dry residues of these products. Lethal and sublethal effects were evaluated in bioassays with the larval and adult stages of both predators. The agrochemicals were classified according to the IOBC guidelines. The insecticide chlorantraniliprole was harmless (class 1) to the larval stage of C. externa and C. quadrifasciata. Azadirachtin, copper 25% + calcium 10%, and deltamethrin were harmless to the adult stage of both insect species. The organophosphates fenitrothion and malathion were harmful (class 4) to both species in the larval and adult stages and should not be used in peach orchards. Therefore, this study demonstrates the importance of toxicity and the lethal and sublethal effects of these agrochemicals to better determine their compatibility with IPM in peach production.

The present study aimed to analyze the chemical composition of five species of the genus Piper ( P. aduncum L.; P. crassinervium Kunth.; P. malacophyllum Prels.; P. gaudichaudianum Kunth.; P. marginatum L.), and assess their toxicity to the adults of Drosophila suzukii (Diptera: Drosophilidae) and the pupal parasitoid Trichopria anastrephae Lima (Hymenoptera: Diapriidae). The major compounds were monoterpene hydrocarbons (5.3–60.9%); oxygenated monoterpenes (13.3%); sesquiterpenes hydrocarbons (8.3–45.3%), oxygenated sesquiterpenes (5.2–58.8%); and arylpropanoids (15.2–29.6%). In bioassays of ingestion and topical application, essential oils (EOs) from P. aduncum , P. gaudichaudianum , and P. marginatum killed approximately 100% of adults of D. suzukii , similarly to the insecticide based on spinetoram (75 mg L −1 ) (96.2% of mortality). Besides, the dry residues from P. aduncum , P. gaudichaudianum , and P. marginatum provided a repellent effect on oviposition (≅ 7 eggs/fruits) and negative effects on egg viability (≅ 2 larvae/fruits) of D. suzukii on artificial fruits. Based on the estimate of the lethal concentration required to kill 90% of exposed flies, EOs from P. aduncum , P. crassinervium , P. gaudichaudianum , P. malacophyllum , and P. marginatum provided low toxicity to the parasitoid T. anastrephae in a bioassay of ingestion and topical application (mortality < 20%), similarly to the water treatment (≅ 5% of mortality). EOs of Piper species tested in this work showed to be promising plant insecticides for the management of D. suzukii .

We evaluated the lethal and sublethal effects of azoxystrobin, cyhalofop-butyl, and thiamethoxam on Telenomus podisi after spraying rice plants in a greenhouse, as well as the degradation kinetics of these compounds over time. Pesticides were sprayed at 50 and 100% of the maximum field recommended concentration for the crop (MFRC). At 0, 5, 10, and 20 days after application of the treatments (DAAT), T. podisi was exposed to leaves containing dry pesticide residues. On these same dates, rice leaves from each treatment were collected for determination of pesticide residues by UHPLC–MS/MS. Based on the results for mortality, parasitism, emergence, and sex ratio of T. podisi , the effects were grouped using a reduction coefficient ( E x ) and classified according to the scale of the International Organization for Biological and Integrated Control (IOBC). The fungicide azoxystrobin (at 50 and 100% MFRC) was the only one classified as harmless (Class 1). The herbicide cyhalofop-butyl was classified as slightly harmful (Class 2) to T. podisi until 5 DAAT. The insecticide thiamethoxam (50 and 100% MFRC), up to 5 DAAT, was classified as harmful (Class 4) on T. podisi . Regarding residue, the initial concentrations (0 DAAT) of azoxystrobin, cyhalofop-butyl, and thiamethoxam at 100% MFRC in rice leaves were 102.14, 210.09, and 36.93 mg kg −1 , respectively. At 50% MFRC, initial waste was approximately half that extracted at 100% MFRC. The estimated half-lives (DT 50 ) were approximately 17, 4, and 5 days for azoxystrobin, cyhalofop-butyl, and thiamethoxam, respectively. Furthermore, we found a positive correlation between effects and residues.

This study evaluated the toxicity of the insecticide spinetoram at different doses [1.25, 1.87, 2.5, 3.75 and 5.0 g of active ingredient/100 L of water - (g of a.i./100 L)] on adults and larvae of C. capitata. Based on the LC50 and LC90 values, spinetoram showed high toxicity against C. capitata adults in the ingestion bioassay (LC50 = 1.95 and LC90 = 5.10 µg a.i./mL) and topical application (LC50 = 3.10 and LC90 = 8.10 µg a.i./mL), and was statistically superior to acetamiprid + etofenprox (ingestion: LC50 = 5.87 and LC90 = 12.04 µg a.i./mL; topical application: LC50 = 14.05 and LC90 = 21.06 µg a.i./mL). However, spinetoram was less toxic than Chlorpyrifos (ingestion: LC50 = 0.95 and LC90 = 3.06 µg a.i./mL; topical application: LC50 = 0.67 and LC90 = 2.45 µg a.i./mL). At a dose of 5.0 g of a.i./100 L, spinetoram was highly toxic against the 1st, 2nd, and 3rd larval instars in immersion bioassays (80% larval mortality). However, it was not effective against larvae inside the fruits when applied via direct spraying in the region opposite to the sites of oviposition by C. capitata. In contrast, spinetoram (5.0 g a.i./100 L) and chlorpyrifos reduced larval viability when applied directly to the oviposition region. In the field, after three applications at intervals of 14 days, spinetoram (5.0 g a.i./100 L) and chlorpyrifos (96 mL a.i./100 L) reduced damage in orange fruits by more than 95%. According to the results, the insecticide spinetoram can be an alternative to chlorpyrifos and acetamiprid + etofenprox for the control of C. capitata. RESUMO: Este estudo avaliou a toxicidade do inseticida espinetoram em diferentes doses [1,25, 1,87, 2,5, 3,75 e 5,0 g de princípio ativo/100 L de água - (g de i.a./100 L)] em adultos e larvas de C. capitata. Com base nos valores de CL50 e CL90, o espinetoram apresentou alta toxicidade contra adultos de C. capitata em bioensaio por ingestão (CL50 = 1,95 e CL90 = 5,10 µg i.a./mL) e após aplicação tópica (LC50 = 3,10 e CL90 = 8,10µg i.a./mL), sendo estatisticamente superior ao acetamiprido + etofenproxi (ingestão: CL50 = 5,87 e CL90=12,04 µg i.a./mL; aplicação tópica: CL50 = 14,05 e CL90 = 21,06 µg i.a./mL). Entretanto, foi menos tóxico que o Clorpirifós (ingestão: CL50 = 0,95 e CL90 = 3,06 µg i.a./mL; aplicação tópica: CL50 = 0,67 e CL90 = 2,45 µg i.a./mL). Na dose de 5,0 g de i.a./100 L, o espinetoram foi altamente tóxico contra larvas de 1º, 2º e 3º instares em bioensaios de imersão (80% de mortalidade larval). No entanto, não foi eficaz contra as larvas no interior dos frutos quando aplicado via pulverização direta na região oposta aos locais de oviposição de C. capitata. Por outro lado, quando aplicado diretamente na região de oviposição, o espinetoram (5,0 g i.a./100 L) e o clorpirifós reduziram a viabilidade larval. No campo, após três aplicações com intervalos de 14 dias, o espinetoram (5,0 g i.a./100 L) e o clorpirifós (96 mL i.a./100 L) reduziram os danos em frutos de laranja em mais de 95%. De acordo com os resultados, o inseticida espinetoram pode ser uma alternativa ao cloripirifós e acetamiprido + etofenproxi para o controle de C. capitata.

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.

This is the first study to assess the physicochemical and biological compatibility of herbicides used in corn crops with entomopathogenic fungi used in the management of Dalbulus maidis in Brazil. The biological index was employed to ascertain the in vitro compatibility of the herbicides with pure spores (not formulated) of tested fungal isolates (Esalq-1296 of Cordyceps javanica and IBCB66 and Simbi BB15 of Beauveria bassiana). The results indicated a significant interaction between herbicides and fungal isolates when colony diameter and colony-forming units (CFU) were considered. Furthermore, changes in physicochemical characteristics were observed in some mixtures of herbicides and mycoinsecticides tested. The number of CFU was significantly reduced as the exposure time increased in the mixtures containing all the herbicides tested. In general, the Esalq-1296 isolate of C. javanica, formulated in a suspension concentrate (Octane®), proved to be more sensitive to the herbicides studied. In vivo bioassays demonstrated that, despite the synergistic effect of the binary mixtures of herbicides and mycoinsecticides on D. maidis mortality, the presence of the herbicide in the mixtures prevented the extrusion of entomopathogens from cadavers; therefore, caution is recommended when combining mycoinsecticides and post-emergent herbicides in tank mixtures aiming to manage D. maidis.

In this study, was evaluated the action lethal and sublethal of three formulations of Annona species extracts (A. mucosa, A. muricata and A. sylvatica) on adults of Ceratitis capitata (Wiedemann, 1852) (Diptera: Tephritidae) and yours parasitoid Diachasmimorpha longicaudata (Ashmead, 1905) (Hymenoptera: Braconidae). In addition, the efficacy of the selected toxic bait formulations was evaluated by mixing them with different food attractants (Anamed™, 3% Biofruit and 7% sugarcane molasses). From the use of the discriminatory concentration (2000 mg L-1), only A. mucosa caused mortality of C. capitata of more than 85% in ingestion and topical application bioassays, equivalent a spinosyn-based insecticide (control positive). In toxic bait formulation with the tested food attractants, the extracts had a residual effect (mortality ≥80% C. capitata) up to 14 days after applying treatments (DAAT) in the absence of rain. Based on the LC90 (1984.20 mg L−1) values estimated from the concentration-response curves for C. capitata, A. mucosa caused less than 40% adult mortality of the parasitoid D. longicaudata in the ingestion bioassay. However, both treatments showed no sublethal effects (parasitism reduction) over time. In addition, in bioassays with and without choice, there was a significant reduction in the number of punctures and galls caused by females and larvae of C. capitata, respectively, in grape berries in the presence of dry residues of all evaluated treatments. The A. mucosa seed extract was considered the most promising product for use in C. capitata management programs, particularly in organic-based systems, due to its selectivity to D. longicaudata.

ABSTRACT Telenomus and Trichogramma species stand out as agents for the biological control in rice crops, and the main strategy for preserving them is the use of selective pesticides. This study aimed at evaluating the toxicity of pesticides used in irrigated rice crop on Telenomus podisi Ashmead (Hymenoptera: Platygastridae) and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Adults of these parasitoids were exposed to dry residues of pesticides, in a completely randomized experiment, with 25 treatments (24 pesticides + control) and four replications. The insecticides clorantraniliprole, flubendiamide and diflubenzuron and the biological insecticides based on Beauveria bassiana and Metarhizium anisopliae were harmless to T. podisi and T. pretiosum. The harmless herbicides were: 2.4-D amine, profoxydim, quinclorac, ethoxysulfuron and saflufenacil. The fungicide epoxiconazole + kresoxim-methyl was also harmless to these two biological control agents. Therefore, these pesticides are indicated for the integrated pest management, in flooded rice areas. RESUMO Espécies de Telenomus e Trichogramma destacam-se como agentes de controle biológico em áreas orizícolas, e a principal estratégia para sua preservação é a utilização de agrotóxicos seletivos. Objetivou-se avaliar a toxicidade de agrotóxicos utilizados em áreas de arroz irrigado sobre Telenomus podisi Ashmead (Hymenoptera: Platygastridae) e Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Adultos desses parasitoides foram expostos a resíduos secos de agrotóxicos, em experimento inteiramente casualizado, com 25 tratamentos (24 agrotóxicos + testemunha) e quatro repetições. Os inseticidas clorantraniliprole, flubendiamida e diflubenzurom e os inseticidas biológicos à base de Beauveria bassiana e Metarhizium anisopliae foram inócuos para T. podisi e T. pretiosum. Os herbicidas inócuos foram: 2,4-D amina, profoxidim, quincloraque, etoxissulfurom e saflufenacil. O fungicida epoxiconazol + cresoxim-metílico também foi inócuo para esses dois agentes de controle biológico. Portanto, esses agrotóxicos são indicados para o manejo integrado de pragas, em áreas de arroz irrigado.

The complex of phytophagous stink bugs is responsible for considerable reductions in the yield potential of soybean crops. Insecticides are usually used for the management of these pests; however, the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Scelionidae) has become a promising alternative due to its mass production and commercialization in Brazil. This study evaluated the efficacy of inoculative releases of T. podisi prior to the crop critical period of stink bug attack. The experiments were carried out in the field during the 2019/20 and 2020/21 crop years, using a drone for parasitoid releases. The combined analysis of both crop years showed the potential replacement of chemical control with biological control with T. podisi in the initial applications. This change did not significantly affect crop yield, thousand-seed weight (TSW), and seed physiological quality assessed in germination and tetrazolium tests. In addition, the treatment with the first application performed with the parasitoid release, followed by two applications of synthetic insecticides (applied fortnightly), showed no significant differences in the number of stink bugs captured in a vertical beating cloth when compared to the farmer’s pattern (three insecticide applications). Moreover, abundance of generalist predators was higher in the control (without application) and in the treatment constituted by two T. podisi releases. Thus, inoculative releases of T. podisi prior to the critical crop period constitute a promising management alternative for the stink bug complex in soybean crops, contributing to the stability and sustainability of the production system.