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Soybean production is usually performed on large scales, requiring simple but efficient pest management to be successful. Soybean fields are inhabited by several species of arthropods, demanding constant development of management practices to prevent pest outbreaks. More recently, stink bugs have become the most important pest group of soybeans in the Neotropics, responsible for up to 60% of the applied insecticides in Brazil. Natural enemies represent an important mortality factor that can keep the damage caused by stink bugs below the economic threshold levels without additional control actions. Thus, Conservation Biological Control (CBC) strategies can be adopted to preserve or even promote the increase in such natural enemies in the fields, or alternatively, massive releases of biocontrol agents in Augmentative Biological Control (ABC) programs could be adopted. Simple practices such as reducing insecticide use (with the adoption of economic thresholds), prioritizing harmless insecticides or biopesticides, and planting resistant soybean cultivars have been adopted in Brazil with positive results. The challenges to increasing the adoption of more complex stink bug management in commodity crops such as soybean may be overcome using the more recent economic incentives in the global agenda of decarbonized agriculture. The potential and challenges of conservation and augmentative biological control are further discussed in this review. [ABSTRACT FROM AUTHOR]

The parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) is often released to manage lepidopteran pests in cotton crops. However, growers rely on multiple insecticide applications to manage cotton pests. A harmonious integration of control tactics is required for proper pest management, and the use of selective insecticides (i.e., those promoting effective pest control while causing little impact on natural enemies) fits within this scope. This study aimed to assess the lethal, sublethal and transgenerational effects of insecticides from varying chemical groups on T. pretiosum. The insecticides were sprayed on parasitized host [Ephestia kuehniella (Zeller), Lepidoptera: Pyralidae] eggs with developing T. pretiosum stages (egg-larva, prepupa, and pupa), and biological traits were assessed following adult emergence. Overall, pupae were more susceptible to insecticides. We found thiodicarb and chlorfenapyr to reduce F0 adult emergence in rates comparable to the positive control (methomyl). Adult F0 deformation was the highest on flupyradifurone-treated organisms, and both the F0 parasitism rate and female survival were reduced by the insecticides (except for teflubenzuron). The sex ratio (proportion female) was affected by thiodicarb and flupyradifurone. Transgenerational effects occurred on adult emergence, which was reduced on the offspring (F1) of thiodicarb, chlorfenapyr, and flupyradifurone treated T. pretiosum. In addition, thiodicarb decreased the F1 sex ratio (≤ 0.33) compared to the other compounds (sex ratio ≥ 0.45). These results indicate that teflubenzuron is the safest insecticide; the other insecticides are non-selective to T. pretiosum. Field and semifield studies are required to confirm the harmfulness of chlorfenapyr, flupyradifurone and thiodicarb toward T. pretiosum. [ABSTRACT FROM AUTHOR]

The egg parasitoid Telenomus remus (Hymenoptera: Platygastridae) is one of the most important natural enemies of Spodoptera frugiperda (Lepidoptera: Noctuidae). The application of chemical insecticides is the main strategy to control this insect pest, although it can affect T. remus and harm integrated pest management (IPM) programmes. This study evaluated the acute lethal (mortality) and sublethal (parasitism and emergence rate, sex ratio, and longevity) effects caused by chlorfenapyr, spinosad, and thiamethoxam + lambda-cyhalothrin by tarsal contact on T. remus adults. The lethal concentration (LC50) of the insecticides showed that thiamethoxam + lambda-cyhalothrin had the highest lethal toxicity on T. remus adults. However, sublethal effects on the F0 generation showed that all insecticides (chlorfenapyr, spinosad, and thiamethoxam + lambda-cyhalothrin) were classified as innocuous, without significant differences in the parasitism rate, emergence rate, and sex ratio compared to the control. Nevertheless, the risk quotient (RQ, mg ai L−1) classified the insecticides thiamethoxam + lambda-cyhalothrin and chlorfenapyr as toxic to T. remus. In contrast, spinosad was classified as slightly to moderately toxic. Also, thiamethoxam + lambda-cyhalothrin, chlorfenapyr, and spinosad did not affect the biological development of T. remus. These results can be used as a basis for integrating chemical and biological control to manage S. frugiperda in an attempt to preserve natural enemies in the field. [ABSTRACT FROM AUTHOR]

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 . [ABSTRACT FROM AUTHOR]

Foliage- and ground-dwelling arthropods provide ecosystem services, including decomposition and biological control of agricultural pests. Despite this, there is little information on the ground-dwelling arthropod community associated with cotton crops and about their role under pest control practices. Identifying these communities and their preservation would assist smallholder cotton growers in considering an Integrated Pest Management (IPM) approach to pest control. In this context, the strategy of using selective- or broad-spectrum insecticides (both applied only once the pests reached an economic threshold) was assessed using field plots set up within non-Bt cotton structured refuge of a grower field measuring the response of both foliage- and ground-dwelling arthropods and yield. The abundance, species richness, dominance indices, and foliage-dwelling predators and pest species and ground-dwelling predators and decomposers were compared between untreated and insecticide treatments, as was the crop yield. In response to pest monitoring, insecticides were applied 5 and 3 times during the 2018 and 2020 growing seasons, respectively. In 2018 and 2020, 16 and 12 foliage-dwelling predator arthropods and 43 and 47 ground-dwelling predator and decomposer arthropods were collected, respectively. During the 2018 season, broad-spectrum insecticide applications reduced the abundance of foliage-dwelling predators, but had no significant impact on the ground-dwelling community. Principal response curves (PRC) indicated a negative impact of broad-spectrum insecticides only on the foliage-dwelling community, particularly among the Formicidae and Araneae species. Insecticide applications in the 2020 season were only required at the end of the crop season and did not significantly influence the foliage- or ground-dwelling communities. The selective insecticide regime yielded as well as the broad-spectrum insecticide regimes higher yielded than untreated plots. These results demonstrated to the small landholders engaging conservation biological control for the first time, the advantages of an IPM approach to pest management. [Display omitted] • Cotton growers in the Brazilian semiarid operate a distinctive farming system. • The cotton yield is limited by rain, lack of adapted technologies, and pest damage. • Insecticides applied only when pest densities reached the economic threshold reduced the impact on beneficial arthropods. • Selective insecticides preserved foliage and ground dwelling arthropods and yield. • The data encourage growers be receptive to a more comprehensive IPM approach in the region. [ABSTRACT FROM AUTHOR]

The use of botanical insecticides could be an alternative efficient pest management in Cucurbitaceae against melonwormDiaphania hyalinataand less harmful to its predator. Few studies jointly assess the efficiency of botanical insecticides, their effects on pest, and their effect on the natural enemy and target crop. Here we examine (1) their impact against the melonwormD. hyalinata, a key pest of Cucurbitaceae, (2) their toxicity to the predatory antParatrechinasp., and (3) their phytotoxicity to pumpkin plants. The botanical insecticides citronella oil and eucalyptus oil were highly toxic toD. hyalinataand they exhibited to be less harmful for the predatory antParatrechinasp. Andiroba oil, eucalyptus oil, garlic extract, and citronella oil caused feeding inhibition of theD. hyalinatalarvae. Eucalyptus oil, andiroba oil, garlic extract, and rotenone inhibited the oviposition ofD. hyalinata. None of the insecticides was phytotoxic to pumpkin plants. Eucalyptus oil and citronella oil have induced high mortality and altered the behavior of target pests. In addition, they were selective for the predatorParatrechinasp. and not exhibited phytotoxicity on pumpkin plants. Eucalyptus oil and citronella oil seem the most promising compounds for incorporation into melonworm management programs, because they induced high mortality and altered the behavior of target pests and were selective for the predatorParatrechinasp. [ABSTRACT FROM PUBLISHER]

Abstract: The parasitic wasp Trichogramma nubilale (Hymenoptera: Trichogrammatidae) is one of the most suitable parasitoids for controlling Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae). Although extensive toxicological tests have been carried out to elucidate the toxicities of insecticides to trichogrammatids, the acute toxicity risks of commonly used insecticides to T. nubilale are not well known. Among the 7 classes of tested chemicals, organophosphates and carbamates had the highest intrinsic toxicity to the parasitoid with LC50 values ranging from 0.081 (0.062–0.12) to 2.10 (1.23–3.47) and from 0.12 (0.11–0.14) to 0.95 (0.87–1.05) mg a.i. per liter, respectively. The phenylpyrazoles (with the exception of butene-fipronil), avermectins, neonicotinoids and pyrethroids induced intermediate toxicity responses with LC50 values ranging from 0.29 to 4.67, 2.36 to 11.27, 1.86 to 311.9, and 10.98–150.3 mg a.i. per liter, respectively. In contrast, insect growth regulators (IGRs) exhibited the least toxicity to the parasitoid with LC50 values ranging from 3452 (3114–3877) to 10,168 (8848–12,027) mg a.i. per liter. A risk quotient analysis indicated that neonicotinoids, avermectins, pyrethroids, IGRs and phenylpyrazoles (with the exception of butene-fipronil) were safe, but organophosphates and carbamates were slightly to moderately toxic or highly toxic to T. nubilale. This study provided informative data for implementing both biological and chemical control strategies in integrated pest management (IPM) of corn lepidopterans. [Copyright &y& Elsevier]

The cytochrome P450 family (P450s) of arthropods includes diverse enzymes involved in endogenous essential physiological functions and in the oxidative metabolism of xenobiotics, insecticides and plant allelochemicals. P450s can also establish insecticide selectivity in bees and pollinators. Several arthropod P450s, distributed in different phylogenetic groups, have been associated with xenobiotic metabolism, and some of them have been functionally characterized, using different in vitro and in vivo systems. The purpose of this review is to summarize scientific publications on arthropod P450s from major insect and mite agricultural pests, pollinators and Papilio sp , which have been functionally characterized and shown to metabolize xenobiotics and/or their role (direct or indirect) in pesticide toxicity or resistance has been functionally validated. The phylogenetic relationships among these P450s, the functional systems employed for their characterization and their xenobiotic catalytic properties are presented, in a systematic approach, including critical aspects and limitations. The potential of the primary P450-based metabolic pathway of target and non-target organisms for the development of highly selective insecticides and resistance-breaking formulations may help to improve the efficiency and sustainability of pest control. [Display omitted] • Pest and pollinator P450s functionally associated with detoxification are reviewed. • P450s associated with xenobiotic detoxification belong to clan 3, but no particular clade. • The systems used for P450 functional validation are critically summarised and presented. • The substrate specificities of different arthropod P450s are summarised. • P450-based metabolic pathway provides potential for safe and selective insecticides. [ABSTRACT FROM AUTHOR]