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Coffee (Coffea arabica L.) is one of the main commodities produced in Brazil. Insecticides like the (systemic) neonicotinoid thiamethoxam are widely used to suppress pest populations during coffee production, in particular the Neotropical leaf miner (Leucoptera coffeella Guérin-MènevillePerrottet, 1842) (Lepidoptera: Lyonetiidae). In addition to its efficacy against this pest species, thiamethoxam is also thought to be a bioactivator of plant metabolism, but has not yet been tested for such activity. Thus, the objectives of the present study were (1) to assess the concentration-response effects of thiamethoxam on the vegetative vigor of coffee seedlings (C. arabica 'Catuaí 144' cultivar) at different concentrations [2, 20, 40, 80 and 200 mg active ingredient (a.i.) kgThe results indicated that thiamethoxam has a deleterious effect on the morphophysiological traits of the plants compromising their development with increase in concentrations. However, leaf area exhibited a different pattern with a peak at 50 mg a.i. kgThiamethoxan exhibited bioactivation effect on leaf at low concentration, but without compromising efficacy against leaf miner populations. Therefore, its proposed metabolism-boosting properties may encourage the unnecessary use of this insecticide, potentially leading to higher selection for insecticide resistance and an eventual decline in its effectiveness against the Neotropical leaf miner. © 2022 Society of Chemical Industry.

Quantitative risk influencing factors (RIFs) are proposed, using the Conjugate Bayesian update approach to analyze 945 collision accidents and incidents cases from the Jiangsu Segment of the Yangtze River over five years from 2012 to 2016. The accident probability is compared under a pairwise comparison mode in order to reflect the relative risk between accidental situations. The Bayesian update mode is constructed to quantitatively evaluate the relative importance of different RIFs. The riskiest segment of Jiangsu Waterways as well the main causations of collisions are identified based on the distributions of collision risk in the six segments of the waterways. The results can support managers to develop the most effective policies to mitigate the collision risk.

Studying the intimate association of arthropods with their physical substrate is both important and challenging. It is important because substrate is a key determinant for organism fitness; challenging because the intricacies of this association are dynamic, and difficult to record and resolve. The advent of electropenetrography (EPG) and subsequent developments allowed researchers to overcome this challenge. Nonetheless, EPG research has been historically restricted to piercing-sucking hemipteran plant pests. Recently, its potential use has been greatly broadened for additional pests with instrument advances. Thus, blood-feeding arthropods and chewing feeders, as well as non-feeding behaviors like oviposition by both pests and parasitoids, are novel new targets for EPG research, with critical consequences for integrated pest management. EPG can explain mechanisms of crop damage, plant or animal pathogen transmission, and the effects of insecticides, antifeedants, repellents, or transgenic plants and animals, on specific behaviors of damage or transmission. This review broadly covers the principles and development of EPG technology, emphasizing controversies and challenges remaining with suggested research to overcome them. In addition, it summarizes 60+ years of basic and applied EPG research, and previews future directions for pest management. The goal is to stimulate new applications for this unique enabling technology. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.

BACKGROUND Animal personality refers to behavioral consistency and propensity. In social insects, little is known about the interplay between colony personality and colony foraging. This study aimed to assess personality traits among colonies of the leaf-cutting ants Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus molestans and examine their behavioral consistency when provided with a toxic substrate, nasturtium leaves [Tropaeolum majus L. (Tropaeolaceae)], with potential as a management tool against these pest species. The association between colony behavioral traits and fungus garden growth was also examined, and thus the efficacy of the colony suppression. RESULTS Behavioral variation was higher between colonies than between subspecies. Behavioral traits were correlated before and after exposure to resource-mediated stress in both subspecies, indicating the existence of behavioral syndrome. The dimensions that contributed most to colony personality (activity, aggressiveness, and boldness) are directly related to colony resource searching and foraging. However, these dimensions diverged in their contribution before and after exposure to nasturtium. Colony activity was the major determinant of fungus garden growth, which is probably a consequence of its relationship with foraging behaviors and maintenance of the fungus garden. CONCLUSION As the personality of a colony is unequally defined by its constituent castes, the relationship and network of interactions are determinants of foraging behaviors with relevant consequences for colony suppression using toxic foraging substrates that impair these relationships and interactions, as nasturtium leaves do. Therefore, it is plausible to say that resource-mediated stress affects colonies personality exhibiting control potential against these species.

BACKGROUND The use of insecticidal solutions containing sodium chloride (NaCl) has been proposed as a more environmentally friendly alternative to managing stink bug infestations of Neotropical soybean fields. The potential sublethal and undesirable effects of this practice have, however, been overlooked, especially with novel insecticides. Here, we have evaluated experimentally whether the addition of NaCl (0.5% w/v) to imidacloprid-containing solutions could alter insecticide toxicity and modify the reproductive responses of the Neotropical brown stink bug Euschistus heros. RESULTS Adding NaCl to imidacloprid solutions significantly increased imidacloprid toxicity against E. heros. The exposure to E. heros to sublethal concentrations of imidacloprid affected the insect's mating abilities in a concentration-dependent manner. The addition of NaCl to solutions containing imidacloprid at concentrations as low as 0.126 μg a.i. cm-2 (i.e. the equivalent to 3% of field rate recommendation) also impacted the sexual behavior of E. heros, reducing mating duration. NaCl-exposed stink bugs, however, exhibited higher fecundity and fertility rates than those insects that were unexposed to NaCl or those that were exposed to sublethal levels of imidacloprid only. CONCLUSIONS The addition of low amounts of NaCl resulted in a higher toxicity of imidacloprid. This practice, however, can also lead to undesirable effects as increasing reproductive output of E. heros that can potentially compromise the management of these insect pests.

Biorational insecticides are composed of natural products, including animals, plants, microbes, and minerals, or are their derivates. The use of biorational products for the management of insect pests has grown intensively in recent years, which has increased their popularity and share on the insecticide global market. Much of these recent increases in the use of biorational insecticides has been derived from the generalized perception that conventional insecticides have undesirable ecological and human health impacts. However, the idea of simply replacing synthetic compounds with biorational insecticides without considering their potential unintended effects can mislead their use and reduce the market life of such pest management tools. A systematic literature survey encompassing over 15 000 scientific manuscripts published between 1945 and 2019 reinforces the bias of focusing on studying the targeted effects while overlooking the potential detrimental effects of biorational products on human health and the environment (e.g. death and negative sublethal effects on pollinators and beneficial arthropods such as parasitoids and predators). Thus, the risks associated with biorational compounds (e.g. control failures, the evolution of resistance, shift in dominance, and outbreaks of secondary or primary pests) need to be revisited and the outcomes of such inquiry could be decisive for their future use in pest management programs. The shortcomings of regulatory processes, knowledge gaps, and the outlook for the use of the biorational products in pest management are discussed. © 2020 Society of Chemical Industry.

RATIONALE Fucus vesiculosus has been described with potential to develop functional foods containing bioactive compounds against various diseases. However, more studies are needed to better understand its functioning and its previously reported bioactivities, mainly at the molecular level. METHODS An untargeted metabolomic study was performed to analyse HepG2 cells exposed to F. vesiculosus aqueous extract, rich in phlorotannins and peptides, during 24 h. This study was carried out using liquid chromatography combined with high-resolution tandem mass spectrometry. RESULTS This metabolomic study showed significant changes in HepG2 metabolites in the presence of the extract, standing out being the increased intensity of various fatty acid amides (oleamide, (Z)-eicos-11-enamide, linoleamide, palmitamide, dodecanamide and stearamide). This group of metabolites is reported in the literature with anticancer and hypocholesterolemic activity, bioactivities also described for F. vesiculosus. The extract induced, likewise, the expression of glutathione indicating its antioxidant effect. CONCLUSIONS This study demonstrated the potential of the compounds present in the F. vesiculosus aqueous extract for the development of natural drugs, nutraceuticals or dietary supplements, justified at the molecular level by changes in cell metabolites related to anticancer and hypocholesterolemic activity. The results here described, using an untargeted metabolomic approach, may contribute to a better understanding of algal behaviour, when used as food, in health-promoting effects.

BACKGROUND The importance and impact of invasive species are usually considered based on their economic implications, particularly the direct damage that they cause. The West Indian drywood termite Cryptotermes brevis (Walker) is an example and is a concern in structural lumber, furniture, and other wood products. Despite its importance, its tropical wood preferences and the wood physical characteristics contributing to resistance have not been investigated to date. Here, we developed wood testing units to allow the X-ray recording of termite colonization and then subsequently tested tropical wood resistance to the termite through free-choice and no-choice bioassays using these wood testing units. The relevance of wood density and hardness as determinants of such resistance was also tested, as was termite mandible wear. RESULTS The wood testing units used allowed the assessment of the termite infestation and wood area loss, enabling subsequent choice bioassays to be performed. While pine (Pinus sp.), jequitiba (Cariniana sp.) and angelim (Hymenolobium petraenum) exhibited the heaviest losses and highest infestations; cumaru (Dipteryx odorata), guariuba (Clarisia racemosa), and purpleheart (Peltogyne sp.) showed the lowest losses and infestations; courbaril (Hymenaea courbaril), eucalyptus (Eucalyptus sp.), and tatajuba (Bagassa guianensis) exhibited intermediary results. CONCLUSION Wood hardness and in particular wood density were key determinants of wood resistance to the termites, which exhibited lower infestations associated with greater mandible wear when infesting harder high-density wood. © 2017 Society of Chemical Industry.

Insecticide resistance is a standing concern for arthropod pest species, which may result in insecticide control failure. Nonetheless, while insecticide resistance has remained a focus of attention for decades, the incurring risk of insecticide control failure has been neglected. The recognition of both problems is paramount for arthropod pest management and particularly so when invasive species notoriously difficult to control and exhibiting frequent cases of insecticide resistance are considered. Such is the case of the putative whitefly species Middle East-Asia Minor I (MEAM1) (Bemisia tabaci b-biotype), for which little information is available in the Neotropics.

Acoustic communication is taxonomically widespread in bark beetles and is proposed to play an important role in a variety of social and defensive behavioural contexts. Yet our understanding of how signals vary between contexts is currently limited. The present study tests the hypothesis that acoustic signals vary between behavioural contexts in the female pine engraver beetle Ips pini (Say) (Coleoptera: Curculionidae: Scolytinae). Female Ips pini produce acoustic chirps using a vertex-pronotal stridulatory organ. Randomly sampled chirps generated under three contexts (i.e. distress, predation and premating) are compared for their duration, number of pulses, interpulse intervals, pulse rate and amplitude envelope shapes. The results obtained show that, during premating events, chirps are significantly longer in duration and tend to have a higher proportion of descending amplitude envelopes than chirps occurring during distress and predation events. Chirps produced during distress and predation conditions are indistinguishable from one another. By contrast to the results from previous bark beetle studies, no support is found for categorizing chirps as ‘interrupted’ or ‘uninterrupted’ types based on temporal patterns. The functional significance of context-dependent variation in chirp characteristics is discussed. Previous studies on acoustic communication in bark beetles are limited as a result of a general lack of objective sampling and measurement criteria for characterizing signals. Recommendations are outlined for future studies on the functions and evolution of acoustic communication in bark beetles.

BACKGROUND The spatial distribution of insects is due to the interaction between individuals and the environment. Knowledge about the within-field pattern of spatial distribution of a pest is critical to planning control tactics, developing efficient sampling plans, and predicting the pests’ damages. The leaf miner Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the main pest in tomato crops in several regions of the world. Despite the importance of this pest, the pattern of spatial distribution of T. absoluta on open-field tomato cultivation remains unknown. Therefore, this study aimed to characterize the spatial distribution of T. absoluta in 22 commercial open-field tomato cultivations with plants at the three phenological development stages by using geostatistical analysis. RESULTS Geostatistical analysis revealed that there was strong evidence for spatially dependent (aggregated) T. absoluta eggs in 19 of the 22 sample tomato cultivations. The maps that were obtained demonstrated the aggregated structure of egg densities at the edges of the crops. Further, T. absoluta was found to accomplish egg dispersal along the rows more frequently than it does between rows. CONCLUSION Our results indicate that the greatest egg densities of T. absoluta occur at the edges of tomato crops. These results are discussed in relation to the behavior of T. absoluta distribution within fields and in terms of their implications for improved sampling guidelines and precision targeting control methods that are essential for effective pest monitoring and management.

A ship that is not under control (NUC) is a typical incident that poses serious problems when in confined waters close to shore. The emergency response to NUC ships is to select the best risk control options, which is a challenge in restricted conditions (e.g., time limitation, resource constraint, and information asymmetry), particularly in inland waterway transportation. To enable a quick and effective response, this article develops a three-stage decision-making framework for NUC ship handling. The core of this method is (1) to propose feasible options for each involved entity (e.g., maritime safety administration, NUC ship, and ships passing by) under resource constraint in the first stage, (2) to select the most feasible options by comparing the similarity of the new case and existing cases in the second stage, and (3) to make decisions considering the cooperation between the involved organizations by using a developed Bayesian network in the third stage. Consequently, this work provides a useful tool to achieve well-organized management of NUC ships.

BACKGROUND The subsequent deposition of an egg clutch by a female parasitoid into a host already parasitised either by itself or a conspecific (i.e. superparasitism) is a counterintuitive adaptive strategy, particularly considering the female parasitoid's ability to recognise the parasitised hosts. Such a scenario suggests that the adaptive value of superparasitism depends on the number of clutches laid in the same host, with consequences for parasitoid progeny yield. Here, we tested whether such is the case for the gregarious parasitoid Palmistichus elaeisis and explored its underlying basis. RESULTS Allowing female parasitoids to lay multiple egg clutches in a single melonworm host pupa, parasitoid progeny and fitness exhibited a peak or optimum at three egg clutches laid per host pupa. In addition, haemocyte count, encapsulation and melanisation decreased with the number of egg clutches laid per host pupa. DISCUSSION An optimum number of three clutches laid per host pupa was detected for P. elaeisis. As immune response via haemocyte production, encapsulation and melanisation decreased with the number of clutches laid per host, the higher parasitoid yield and fitness observed is the likely consequence of a compromised immune response coupled with an accommodative (i.e. scramble) larval competitive strategy allowing enough resources for optimum balance of parasitoid number and quality produced. © 2017 Society of Chemical Industry.

This article proposes a modified cognitive reliability and error analysis method (CREAM) for estimating the human error probability in the maritime accident process on the basis of an evidential reasoning approach. This modified CREAM is developed to precisely quantify the linguistic variables of the common performance conditions and to overcome the problem of ignoring the uncertainty caused by incomplete information in the existing CREAM models. Moreover, this article views maritime accident development from the sequential perspective, where a scenario- and barrier-based framework is proposed to describe the maritime accident process. This evidential reasoning-based CREAM approach together with the proposed accident development framework are applied to human reliability analysis of a ship capsizing accident. It will facilitate subjective human reliability analysis in different engineering systems where uncertainty exists in practice.© 2017 Society for Risk Analysis. Language: en

Background Hypothenemus hampei Ferrari (Coleoptera: Curculionidae) is the main pest of coffee due to the damage caused to coffee berries. Effective management methods and prevention of insecticide resistance are urgently needed against this insect. Bioassays were conducted to assess the effects of the diamide insecticide cyantraniliprole on H. hampei. Cyantraniliprole is the most recent compound registered against this species after the phasing out of endosulfan, the main insecticide historically used against the coffee borer for the past 30 years. Toxicity, survival, progeny production, respiration rate, and behavioral responses to cyantraniliprole were evaluated. Results Cyantraniliprole was toxic to adult H. hampei (LC50 = 0.67 mg mL-1 and LC90 = 1.71 mg mL-1 ). Adult survival was 95% without exposure to cyantraniliprole, decreasing to 52% in insects exposed to LC50 cyantraniliprole and 27% in insects treated with LC90 cyantraniliprole. Furthermore, H. hampei showed reduced mobility on insecticide-treated surfaces. The insecticide also led to a decrease in the respiration rate of H. hampei for up to 3 h after exposure, altering behavioral responses and locomotor activity. Conclusion Cyantraniliprole exhibits lethal and sublethal effects on H. hampei and can be used in rotation in integrated pest management programs for control of this species in coffee cultivation systems. © 2019 Society of Chemical Industry.

Insecticide resistance is a broadly recognized ecological backlash resulting from insecticide use and is widely reported among arthropod pest species with well-recognized underlying mechanisms and consequences. Nonetheless, insecticide resistance is the subject of evolving conceptual views that introduces a different concept useful if recognized in its own right - the risk or likelihood of control failure. Here we suggest an experimental approach to assess the likelihood of control failure of an insecticide allowing for consistent decision-making regarding management of insecticide resistance. We also challenge the current emphasis on limited spatial sampling of arthropod populations for resistance diagnosis in favor of comprehensive spatial sampling. This necessarily requires larger population sampling - aiming to use spatial analysis in area-wide surveys - to recognize focal points of insecticide resistance and/or control failure that will better direct management efforts. The continuous geographical scale of such surveys will depend on the arthropod pest species, the pattern of insecticide use and many other potential factors. Regardless, distance dependence among sampling sites should still hold, following the maxim that the closer two things are, the more they resemble each other, which is the basis of Tobler's First Law of Geography. © 2016 Society of Chemical Industry.

Solvothermal reaction of zinc(II) and copper(II) salts with 3,3′′-dipropoxy-[1,1′:4′,1′′-terphenyl]-4,4′′-dicarboxylic acid (H2L) gave rise to the 1D and 2D metal–organic frameworks (MOFs) [Zn(L)(dmf)2]n (1), [Zn2(L)(NO3)2(4,4′-bipyridine)2]n·n(DMF) (2), [Cu(L)(H2O)2]n·2n(H2O) (3), and [Cu3(OH)2(L)2]n·n(H2O) (4), which were characterized by elemental analysis, FTIR spectroscopy, and X-ray single-crystal diffraction. MOFs 1 and 3 have zigzag- and linear-type 1D structures, respectively, whereas 2 and 4 possess rectangular grid- and layer-type 2D structures. In 2 and in 4, a dinuclear ZnII cluster (C2O4Zn2) and a trinuclear µ3-hydroxo-bridged CuII cluster [Cu3(OH)2]n, respectively, act as building block units. These frameworks act as heterogeneous catalysts (the Zn-MOFs are more active than Cu-MOFs, and 1 is the most efficient) for the cyanosilylation of aldehydes with trimethylsilyl cyanide at room temperature. These MOF-based heterogeneous catalysts can be easily recovered and reused, at least over a few consecutive cycles, without losing activity.

BACKGROUND Random mating is a common assumption in studies of insecticide resistance evolution, but seldom tested despite its potential consequences. Therefore, the existing evidence of female choice and insecticide resistance in populations of the maize weevil (Sitophilus zeamais), a key pest of stored cereals, led to the assessment of mating preferences and their association with insecticide resistance in this species. RESULTS Mixed lines of a maize weevil colony were established from field-collected populations, which after 5 months of natural breeding were selected for deltamethrin resistance for five generations, reaching over 100-fold resistance. Mating preference was significantly based on the partner size, measured as body mass (χ2 = 5.83, df = 1, P = 0.016). Susceptible females preferred heavier males for mating (χ2 = 5.83, df = 1, P = 0.015), a trait that was more frequently associated with deltamethrin resistance (χ2 = 7.38, df = 1, P = 0.007). Deltamethrin resistance compromised daily fertility, although the reduced offspring production observed in matings between susceptible females and resistant males was negligible. CONCLUSION Susceptible female weevils prefer larger (and heavier) males to mate, a trait associated with deltamethrin resistance, favouring the maintenance and spread of the resistant phenotype in the population. © 2016 Society of Chemical Industry

Backswimmers (Hemiptera: Heteroptera: Notonectidae) are insect predators in a wide variety of freshwater habitats. These insects are well known due to their role as mosquito biocontrol agents, their capability of preying on immature fishes and frogs, and because they are often the first to colonize aquatic habitats. As a consequence, these predators may face intended or unintended insecticide (e.g., insecticides) exposures that may lead to death or to impairment of essential behaviors (e.g., swimming and position in the water column). Here, we evaluated the toxicity of deltamethrin (a type II pyrethroid insecticide stressor) and the swimming activity of the backswimmers Buenoa tarsalis and Martarega bentoi. Concentration-mortality and survival bioassays were conducted with the insecticide, which were compared with controls without deltamethrin. Deltamethrin was 26-fold more toxic to B. tarsalis (LC50 = 4.0 ng a.i/L) than to M. bentoi (LC50 = 102.5 ng a.i/L). The pattern of occupation of B. tarsalis, but not of M. bentoi, in the water column was also disrupted, and B. tarsalis was forced to stay near the water surface longer with exposure to deltamethrin. Thus, based on our findings, B. tarsalis was less resilient to deltamethrin exposure compared with M. bentoi, and the efficacy of swimming-dependent processes might be negatively affected (e.g., prey catching, partner encounter, and anti-predator behaviors) for B. tarsalis under deltamethrin exposure. This article is protected by copyright. All rights reserved

Leafminer flies are phytophagous and cosmopolitan pests. Leafminer fly outbreaks and damage to cultivated plants have steadily increased in several regions in the world. In the present study, we report host range, geographical distribution, Wolbachia infection and mitochondrial strains of leafminer fly species from eastern Brazil. Four leaf miner fly species were identified using cytochrome c oxidase subunit I DNA barcoding. Liriomyza sativae is the main pest as a result of its high polyphagy and wide distribution. Liriomyza brassicae, Liriomyza huidobrensis and Calycomyza malvae are important in Brassicaceae, Curcubitaceae and Malvaceae crops, respectively. There is no relationship among host range, geographical distribution and mitochondrial strains of leafminer fly species. We did not find Wolbachia infection in any of the specimens collected. Phylogeographical analyses suggests that there are four strains of L. sativae in the world, one of which is endemic from Brazil. The lack of shared haplotypes between Brazilian specimens and those from other world regions indicates the absence of recent gene flow of leafminer flies from Brazil with specimens from Americas and Old world. The exception is L. brassicae, which exhibits one haplotype shared among Brazil, Philippines and Sri Lanka. The host range identification and geographical isolation of leafminer fly species from Brazil comprise useful information for quarantine and pest management purposes.

BACKGROUND The Guatemalan potato tuber moth, Tecia solanivora, has been the most important pest species in Hispanico-American potato fields since its first record on potatoes in 1956 in Guatemala. This insect pest has been spreading to other parts of the world, including the Canary Islands in Europe. The tuber moth control relies heavily on the use of insecticides, including pyrethroids. Here, we assessed the likelihood of control failures and performed concentration-response bioassays in five Colombian strains of T. solanivora to evaluate their susceptibilities to the pyrethroid permethrin. RESULTS Evidence of control failures was observed in four strains tested, which exhibited moderate resistance levels (i.e., ranging from 5.4- to 24.4-fold). However, no spatial dependence was observed between the permethrin LC50 values and the geographic distances among the tuber moth strains. In order to evaluate whether permethrin resistance was mediated by potential mutations in the para-type sodium channels of T. solanivora, the IIS4–IIS6 region of the para gene was PCR-amplified and sequenced from the five strains tested. As demonstrated across a range of different arthropod species that exhibited knockdown resistance (kdr), we observed a single point substitution (L1014F) at high frequencies in the para gene of all four resistant strains. CONCLUSIONS This is the first identification of a target-site alteration based resistance in the Guatemalan potato tuber moth T. solanivora, which is widespread and exhibits high frequencies among geographically distant strains indicating that pyrethroids are probably becoming ineffective for the control of this pest species.

BACKGROUND The presence of fitness costs of resistance to Bacillus thuringiensis (Bt) insecticidal proteins in insect populations may delay or even reverse the local selection of insect resistance to Bt transgenic crops, and deserves rigorous investigation. Here we assessed the fitness costs associated with Cry1Fa resistance in two strains of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), derived from field collections in different Brazilian regions and further selected in the laboratory for high levels of resistance to Cry1Fa using leaves of TC1507 corn. RESULTS Fitness components were compared using paired resistant and susceptible strains with similar genetic backgrounds and F1 generations from reciprocal crosses, all of them reared on non-transgenic corn leaves. No apparent life history costs in the larval stage were observed in the Bt-resistant strains. Moreover, the resistance remained stable for seven generations in the absence of selection, with no decrease in the proportion of resistant individuals. Larval respiration rates were also similar between resistant and susceptible homozygotes, and heterozygotes displayed respiration rates and demographic performance equal or superior to those of susceptible homozygotes. CONCLUSION In combination, these results indicate the lack of strong fitness costs associated with resistance to Cry1Fa in the fall armyworm strains studied. These findings suggest that Cry1Fa resistance in S. frugiperda populations is unlikely to be counterselected in Cry1Fa-free environments. © 2016 Society of Chemical Industry

BACKGROUND The abundance and contribution of the neotropical brown stink bug, Euschistus heros (F.), and the redbanded stink bug, Piezodorus guildinii (West.), to the composition of insect pests of soybean, Glycine max (L.), fields have changed both spatially and temporally in neotropical soybean production areas. Therefore, we assessed the competitiveness of each species in direct competition experiments following an additive series. We performed mixed (adult) insect infestations in soybean plants and evaluated the fitness of each species and the soybean yield. RESULTS While the competitive ability of E. heros was significantly compromised by increments in conspecifics and heterospecifics (i.e. P. guildinii), the competitive ability of P. guildinii was compromised by the presence of heterospecifics (i.e. E. heros). The reproductive output of P. guildinii remained unaffected by increments in E. heros or of P. guildinii. Intriguingly, despite the fact that P. guildinii apparently lost the competition with E. heros, almost no pod production was observed in any plant colonised by the former. CONCLUSIONS The higher abundance of E. heros in neotropical soybean fields seems to result from higher competitive ability than its heterospecific competitor P. guildinii, which may prevent the higher losses caused by P. guildinii. © 2016 Society of Chemical Industry

The use of predatory mites as the sole management tactic in biological control programmes frequently does not fully and reliably prevents damage of phytophagous mites on plants. Therefore, as an alternative, the integration of predatory mites with acaricides can provide more effective control of phytophagous mites than that of the predators only. However, for such integration, acaricides minimal negative impacts on predatory mites are required. In this study, we evaluated the sublethal effects of three acaricides on the foraging behaviour of Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae) in a coconut production system. The acaricides were assessed for interference with the location of prey habitat using a Y-tube olfactometer and for interference with the location of the prey colony within the habitat using a video-tracking system. In addition to the choice of odour source, the time required and the distance walked to make the choice were assessed. The acaricides tested were abamectin, azadirachtin and fenpyroximate. The predatory mite preferred coconuts infested with the coconut mite Aceria guerreronis Keifer (Acari: Eriophyidae) over uninfested coconuts when not exposed to acaricides. However, when exposed to acaricides, the predator did not distinguish between infested and uninfested fruits. When exposed to abamectin, N. baraki spent more time resting and walked greater distances before making the choice of an odour source. Thus, the acaricides impair the ability of the predatory mite N. baraki to locate a prey habitat and to locate a prey within that habitat. The acaricides differentially affected prey foraging by interfering with odour perception.

This article develops a Bayesian belief network model for the prediction of accident consequences in the Tianjin port. The study starts with a statistical analysis of historical accident data of six years from 2008 to 2013. Then a Bayesian belief network is constructed to express the dependencies between the indicator variables and accident consequences. The statistics and expert knowledge are synthesized in the Bayesian belief network model to obtain the probability distribution of the consequences. By a sensitivity analysis, several indicator variables that have influence on the consequences are identified, including navigational area, ship type and time of the day. The results indicate that the consequences are most sensitive to the position where the accidents occurred, followed by time of day and ship length. The results also reflect that the navigational risk of the Tianjin port is at the acceptable level, despite that there is more room of improvement. These results can be used by the Maritime Safety Administration to take effective measures to enhance maritime safety in the Tianjin port.

Transgenic maize (Zea mays L., Poaceae) event TC1507, producing the Cry1F protein of Bacillus thuringiensis Berliner, has been used for management of the fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), in Brazil since 2009. A strain of S. frugiperda, obtained from field collections of larvae in TC1507 maize in Minas Gerais state in 2010, was selected in the laboratory for resistance to Cry1F using leaves of TC1507 maize in two selection regimes. Continuous exposure of larvae to Cry1F was more effective than exposure for 6, 8, and 10 days in the selection of resistant S. frugiperda individuals. With only four generations of laboratory selection, a strain with high levels of resistance to Cry1F was obtained, as indicated by the survival of insects reared on leaves of TC1507 maize plants and by the more than 300-fold resistance level measured in bioassays with the purified Cry1F protein. Importantly, reciprocal crosses between control and the Cry1F-selected strains revealed that the resistance is autosomal and incompletely recessive, and the response obtained in the backcross of the F1 generation with the resistant strain was consistent with simple monogenic inheritance. Additionally, there were no apparent fitness costs associated with resistance either for survival or larval growth on non-Bt maize leaves. Our findings provide experimental evidence for rapid evolution of Cry1F resistance in S. frugiperda in the laboratory and further reinforce the potential of this species to evolve field resistance to the TC1507 maize as previously reported. The resistant strain isolated in this study provides an opportunity to estimate the resistance allele frequency in the field and to determine the biochemical and molecular basis of the resistance, which should provide further information to assist in the resistance management of S. frugiperda on transgenic maize producing B. thuringiensis proteins.

The preference–performance hypothesis predicts that moth behaviour links plant variations with caterpillar attack and distribution, and the plant-age hypothesis states that specialist herbivores are more successful in exploring younger plant tissue. We integrated these predictions to investigate underlying mechanisms by which moths and caterpillars of Plutella xylostella L. (Lepidoptera: Plutellidae) track and exploit within-plant variability of leaf age and stratification. We measured leaf proteins, glucosinolates and fibre, as well as larval choice, developmental performance, and moth oviposition preference with regard to leaf age classes (young, mature and senescent) of three varieties (collard, cauliflower and cabbage) of the main host plant Brassica oleracea L. Larvae consistently fit the prediction that specialist herbivores prefer and perform better on young, upper leaves that have the highest protein level, despite the highest content of defence compounds. Conversely, moths laid more eggs on fibrous and less nutritious leaves from the lower and senescent stratum. We argue that the leaf stratification of host plants imposes conflicting selective pressures concerning offspring feeding and protection on adult females. If egg mortality is catastrophic on the upper nutritious leaves in a particular microclimatic context (e.g. sun, heat, winds, drought or rain-washing), then oviposition preference will remain for the suboptimal lower and senescent leaves. The ability of larvae to spread upwards over the plant to access the more nutritious leaf stratum is critical when eggs are preferentially laid on the protective low-quality leaves.

Because of their natural origin, biopesticides are assumed to be less harmful to beneficial insects, including bees, and therefore their use has been widely encouraged for crop protection. There is little evidence, however, to support this ingrained notion of biopesticide safety to pollinators. Because larval exposure is still largely unexplored in ecotoxicology and risk assessment on bees, an investigation was performed on the lethal and sublethal effects of a diet treated with 2 bioinsecticides, azadirachtin and spinosad, on the stingless bee, Melipona quadrifasciata, which is one of the most important pollinators in the Neotropics. Survival of stingless bee larvae was significantly compromised at doses above 210 ng a.i./bee for azadirachtin and 114 ng a.i./bee for spinosad. No sublethal effect was observed on larvae developmental time, but doses of both compounds negatively affected pupal body mass. Azadirachtin produced deformed pupae and adults as a result of its insect growth regulator properties, but spinosad was more harmful and produced greater numbers of deformed individuals. Only spinosad compromised walking activity of the adult workers at doses as low as 2.29 ng a.i./bee, which is 1/5000 of the maximum field recommended rate. In conclusion, the results demonstrated that bioinsecticides can pose significant risks to native pollinators with lethal and sublethal effects; future investigations are needed on the likelihood of such effects under field conditions. Environ Toxicol Chem 2015;34:2149–2158. © 2015 SETAC