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Understanding the mechanisms responsible for anxiety disorders is a major challenge. Avoidance behavior is an essential feature of anxiety disorders. The two-way avoidance test is a preclinical model with two distinct subpopulations-the good and poor performers-based on the number of avoidance responses presented during testing. It is believed that the habenula subnuclei could be important for the elaboration of avoidance response with a distinct pattern of activation and neuroinflammation. The present study aimed to shed light on the habenula subnuclei signature in avoidance behavior, evaluating the pattern of neuronal activation using FOS expression and astrocyte density using GFAP immunoreactivity, and comparing control, good and poor performers. Our results showed that good performers had a decrease in FOS immunoreactivity (IR) in the superior part of the medial division of habenula (MHbS) and an increase in the marginal part of the lateral subdivision of lateral habenula (LHbLMg). Poor performers showed an increase in FOS in the basal part of the lateral subdivision of lateral habenula (LHbLB). Considering the astroglial immunoreactivity, the poor performers showed an increase in GFAP-IR in the inferior portion of the medial complex (MHbl), while the good performers showed a decrease in the oval part of the lateral part of the lateral complex (LHbLO) in comparison with the other groups. Taken together, our data suggest that specific subdivisions of the MHb and LHb have different activation patterns and astroglial immunoreactivity in good and poor performers. This study could contribute to understanding the neurobiological mechanisms responsible for anxiety disorders.

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Predator diversity in a system can have different results on the biological control of pests. Positive results can arise if natural enemies have niche complementarity, whereas negative effects can occur when one enemy interferes with heterospecifics-e.g., via intraguild predation-resulting in weaker pest suppression. Nevertheless, a coexistence is possible if enemies use the resource differentially leading to resource partitioning, and/or if the intraguild prey has some competitive advantage over the intraguild predator-i.e., is better at exploiting the shared resource or exhibits avoidance behavior. In this study, we conducted a series of field-sampling and semifield experiments to elucidate the spatiotemporal association patterns of the coccinellids Eriopis connexa (Germar) and Cycloneda sanguinea L. (Coleoptera: Coccinellidae) and determine how the trophic interactions between them could affect the biological control of aphids. We found that both coccinellid species coexist in sweet-pepper crops over time, and this coexistence could be explained by a temporal niche complementarity. Despite cooccurring spatially, they were segregated at the leaf level, which segregation can be explained by an avoidance behavior to prevent negative trophic interactions, such as cannibalism and intraguild predation. Under semifield conditions, the possible negative trophic interactions did not affect the control of aphids when both species were present, but the density of C. sanguinea was reduced at the end of the experiment. These results suggest that biological control strategies that include both species would be positive for the control of aphids on the basis of these considerations.

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Isoxaflutole (IFT) é um herbicida utilizado para o controle em pré-emergência de uma ampla variedade de plantas daninhas de folha larga e gramíneas, especialmente quando há resistência a outros herbicidas, como glyphosate e atrazine. Apesar de seu potencial como herbicida ter sido identificado no início dos anos 90, IFT ainda é considerado um ingrediente ativo novo no Brasil e pouco se sabe sobre seus efeitos, principalmente acerca da ecotoxicidade dos produtos formulados para grupos da macro e mesofauna do solo. Este estudo teve como objetivo avaliar efeitos comportamentais, agudos e crônicos (fuga, letalidade e reprodução) do produto comercial Provence® 750 WG (750 g i.a. L-1 isoxaflutole) nos organismos de teste Eisenia andrei (minhoca) e Folsomia candida (colêmbolo) usando normas padronizadas ISO. Os resultados mostraram que as minhocas apresentam comportamento de fuga apenas em doses >300 vezes a dose de campo e redução na reprodução em doses >150 vezes a dose de campo. Para os colêmbolos não foi obtida resposta de fuga, letalidade ou reprodução nas doses avaliadas. A partir dos resultados de laboratório, presume-se que o produto comercial Provence® não apresenta toxicidade para minhocas e colêmbolos, mesmo em doses muito acima à dose de campo, garantindo a segurança das comunidades do solo.

Isoxaflutole (IFT) is a pre-emergence herbicide used to control of a wide range of broadleaf and grass weeds, especially those resistant to other herbicide classes, such as glyphosate and atrazine. Although its herbicidal potential was identified in the early 90s, IFT is still a new active ingredient in Brazil and little is known about its effects, mainly regarding to ecotoxicity of formulated products to soil macro and mesofauna groups. This study aimed to assess behavioral, acute, and chronical effects (avoidance, lethality, and reproduction) of the commercial product ProvenceTM 750 WG (750 g a.i. L-1 isoxaflutole) on the test organisms Eisenia andrei (earthworms) and Folsomia candida (collembolans) using standardized ISO guidelines. The results showed the avoidance of the earthworm species only at >300 times the predicted field doses, as well as a decrease in reproduction over >150 times the predicted field dose. Neither the avoidance, nor lethality or reproduction response were found for the collembolan species. The laboratory results showed that it is possible to assume that ProvenceTM is not toxic to earthworms and collembolans, even at the highest field dose applied, ensuring the safety of soil communities.

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Isoxaflutole (IFT) é um herbicida utilizado para o controle em pré-emergência de uma ampla variedade de plantas daninhas de folha larga e gramíneas, especialmente quando há resistência a outros herbicidas, como glyphosate e atrazine. Apesar de seu potencial como herbicida ter sido identificado no início dos anos 90, IFT ainda é considerado um ingrediente ativo novo no Brasil e pouco se sabe sobre seus efeitos, principalmente acerca da ecotoxicidade dos produtos formulados para grupos da macro e mesofauna do solo. Este estudo teve como objetivo avaliar efeitos comportamentais, agudos e crônicos (fuga, letalidade e reprodução) do produto comercial Provence® 750 WG (750 g i.a. L-1 isoxaflutole) nos organismos de teste Eisenia andrei (minhoca) e Folsomia candida (colêmbolo) usando normas padronizadas ISO. Os resultados mostraram que as minhocas apresentam comportamento de fuga apenas em doses >300 vezes a dose de campo e redução na reprodução em doses >150 vezes a dose de campo. Para os colêmbolos não foi obtida resposta de fuga, letalidade ou reprodução nas doses avaliadas. A partir dos resultados de laboratório, presume-se que o produto comercial Provence® não apresenta toxicidade para minhocas e colêmbolos, mesmo em doses muito acima à dose de campo, garantindo a segurança das comunidades do solo.(AU)

Isoxaflutole (IFT) is a pre-emergence herbicide used to control of a wide range of broadleaf and grass weeds, especially those resistant to other herbicide classes, such as glyphosate and atrazine. Although its herbicidal potential was identified in the early 90s, IFT is still a new active ingredient in Brazil and little is known about its effects, mainly regarding to ecotoxicity of formulated products to soil macro and mesofauna groups. This study aimed to assess behavioral, acute, and chronical effects (avoidance, lethality, and reproduction) of the commercial product ProvenceTM 750 WG (750 g a.i. L-1 isoxaflutole) on the test organisms Eisenia andrei (earthworms) and Folsomia candida (collembolans) using standardized ISO guidelines. The results showed the avoidance of the earthworm species only at >300 times the predicted field doses, as well as a decrease in reproduction over >150 times the predicted field dose. Neither the avoidance, nor lethality or reproduction response were found for the collembolan species. The laboratory results showed that it is possible to assume that ProvenceTM is not toxic to earthworms and collembolans, even at the highest field dose applied, ensuring the safety of soil communities.(AU)

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Animal-pollinated plants can be susceptible to changes in pollinator availability. Honeydew-producing treehoppers frequently occur on inflorescences, potentially enhancing ant-mediated negative effects on pollination services. However, the effect of ant-attended, honeydew-producing insects on plant reproduction remains uncertain. We recorded the abundance of treehoppers and ants on Byrsonima intermedia (Malpighiaceae), and monitored floral visitors in a Brazilian cerrado savanna. We manipulated the presence of ants and ant-treehopper associations on inflorescences to assess their effect on pollination and fruit formation. We used dried ants pinned to inflorescences to evaluate the effect of ant presence and ant identity on potential pollinators. Results show that the presence of treehoppers increases ant abundance on flowers and disrupts pollination by oil-collecting bees, decreasing the frequency and duration of floral visits and reducing fruit and seed set. Treehopper herbivory has no direct effect on fruit or seed production, which are independent of treehopper density. Pinned ants promote avoidance by floral visitors, reducing the number of visits. Ant identity mediates visitation decisions, with Ectatomma brunneum causing greater avoidance by floral visitors than Camponotus rufipes. Field videos show that pollinating bees are harassed by ants near flowers, prompting avoidance behavior by the bees. This is the first demonstration of indirect effects by honeydew-gathering ants, via disrupted pollination, on plant reproduction in tropical cerrado savanna. Our results highlight the importance of studying other interactions near flowers, in addition to just observing pollinators, for a proper understanding of plant reproduction.

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The objective of the present study was to determine whether blow flies (Diptera: Calliphoridae) are able to identify larvae of an intraguild predator species in the substrate and avoid laying eggs there. Blow flies oviposited in traps with different treatments: substrate only and substrate with larvae of Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), or Chrysomya putoria (Wiedemann, 1830). Ch. megacephala, Ch. putoria, and Lucilia eximia (Wiedemann, 1819) avoided laying eggs in the trap containing Ch. albiceps larvae. Cochliomyia macellaria (Fabricius, 1775) did not oviposit differently in each substrate but had overall low abundance. The prevalence of species on corpses may be influenced by the ability of the species to detect the presence of other species, mainly predators. In this sense, intraguild predation may result in misinterpretations of a crime scene and should be considered when assessing the minimum postmortem interval.

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The massive use of glyphosate (GLY) in several countries has increased the interest in investigating its potential adverse effects in non-target organisms. The aim of the present study was to assess the potential effects in survival and reproduction; avoidance behavior and oxidative stress under short-term (48 h) and subchronic exposures (28 days) to GLY in the earthworm Octolasion cyaneum. After 48 h no significant changes in the behavior was observed. In addition, a lower catalase activity at 498 µg GLY kg(-1) dry soil section relative to earthworms from the control section was obtained. After 28 days of exposure inhibition of glutathione S-transferase activity was observed at 535 µg GLY kg(-1) dry soil while no changes in the other endpoints were detected. These results indicate that environmentally relevant concentrations of GLY (up to 996 µg GLY kg(-1) dry soil) did not exert a toxic effect to O. cyaneum.

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