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PREMISE: Legumes establish mutualistic interactions with pollinators and nitrogen (N)-fixing bacteria that are critical for plant reproduction and ecosystem functioning. However, we know little about how N-fixing bacteria and soil nutrient availability affect plant attractiveness to pollinators. METHODS: In a two-factorial greenhouse experiment to assess the impact of N-fixing bacteria and soil types on floral traits and attractiveness to pollinators in Chamaecrista latistipula (Fabaceae), plants were inoculated with N-fixing bacteria (NF+) or not (NF-) and grown in N-rich organic soil (+N organic soil) or N-poor sand soil (-N sand soil). We counted buds and flowers and measured plant size during the experiment. We also measured leaf, petal, and anther reflectance with a spectrophotometer and analyzed reflectance curves. Using the bee hexagon model, we estimated chromatic contrasts, a crucial visual cues for attracting bees that are nearby and more distant. RESULTS: NF+ plants in -N sand soil had a high floral display and color contrasts. On the other hand, NF- plants and/or plants in +N organic soil had severely reduced floral display and color contrasts, decreasing floral attractiveness to bee pollinators. CONCLUSIONS: Our findings indicate that the N-fixing bacteria positively impact pollination, particularly when nutrients are limited. This study provides insights into the dynamics of plant-pollinator interactions and underscores the significant influence of root symbionts on key floral traits within tropical ecosystems. These results contribute to understanding the mechanisms governing mutualisms and their consequences for plant fitness and ecological dynamics.

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Calliphoridae are widespread globally and can inhabit a variety of habitats. In this brief report, we assessed the appeal of Chrysomya rufifacies to resources that were previously inhabited by Lucilia sericata and L. cuprina, both common carrion colonizers. Two hundred adult male and female (1:1) C. rufifacies were released under controlled conditions into clear plastic cages (45 x 45 x 45 cm) with four types of substrates: beef-liver; liver with 100 third-instar larvae of L. cuprina; (III) liver containing 100 third-instar larvae of L. sericata; and liver containing 100 third-instar larvae of C. rufifacies. Each substrate was left in place for 24 hours at the end of a tube connected to the cage, where sticky traps were positioned to capture flies that might have been attracted to a specific substrate. The results indicate variations in the attraction of flies to different types of livers colonized by larvae of various species. It is suggested that flies may have specific preferences depending on the species of larvae present in the substrate. The liver without larvae was the preferred choice, while beef liver with C. rufifacies larvae was the least attractive. Results of statistical tests indicated that there is independence between attractiveness preference and the presence of C. rufifacies flies. Although there is a trend among certain levels of the variables in the correspondence analysis, these relationships are not statistically significant. However, they indicate specific patterns of association between different groups of flies and species of larvae. This study demonstrated that C. rufifacies does not show reduced attraction to any of the resources. A tetrahedron olfactometer device has been used for the first time in a behavioral study of C. rufifacies flies. This may enable future studies to enhance the understanding of fly behavior.

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The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera, Noctuidae), is a well-known agricultural pest in its native range, North and South America, and has become a major invasive pest around the globe in the past decade. In this review, we provide an overview to update what is known about S. frugiperda in its native geographic ranges. This is followed by discussion of studies from the invaded areas to gain insights into S. frugiperda's ecology, specifically its reproductive biology, host plant use, status of insecticide resistance alleles, and biocontrol methods in native and invasive regions. We show that reference to host strains is uninformative in the invasive populations because multidirectional introduction events likely underpinned its recent rapid spread. Given that recent genomic analyses show that FAW is much more diverse than was previously assumed, and natural selection forces likely differ geographically, region-specific approaches will be needed to control this global pest.

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Alphitobius diaperinus is one of the most significant pests in the poultry industry. Identifying the role of self-produced chemical signals can help control it. Here, we exposed adults to the olfactory signals of other adults of similar and different genders (either males or females) and sexual experiences (i.e., virgin and experienced) to assess their long-range attractiveness and, at short-range, their mating behavior responses (i.e., touching, mounting, and copulation). In olfactometric experiments, our results indicate that adults are attracted to the olfactory signals of other male adults, independently of gender, or sexual condition, indicating the presence of generalized long-range attractive signals, in contrast to female signals, can be both factor-dependent. However, in mating experiments, virgin males developed more robust mating responses (i.e., they mount and copulate longer with females) compared to sexually experienced males, even though they both have similar precopulatory behavioral responses (i.e., time of antennal and leg touching). These results address the importance of short-range chemical signals in eliciting copulation. Furthermore, when virgins of both genders were tested, their mating responses were significantly longer than any other pair combination, indicating that sexual experience also affects mating behavior. Chemical analyses of adult extracts showed that sexual experience, but not gender, is linked to differences in chemical profiles of adults, primarily involved in short-range signaling. These findings provide new insights into the attractiveness and mating responses of A. diaperinus and the role of sexual experience in shaping the behavior and chemical profile of insects that mate multiple times during their lifetime.

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Microplastics (MPs) have been reported in fish species from several freshwater environments. However, the mechanisms underlying MPs ingestion by fish are still unclear, although they are important to determine the pathway of MPs along freshwater environments food webs. Here, we investigates a fundamental question of why wild freshwater fish ingest plastic. To address this, we conducted a laboratory experiment to assess MP fragments intake according to color (red, green, yellow, white, black, and blue) by a small omnivorous fish species Psalidodon eigenmanniorum (Characidae). Results showed that yellow and blue were the most consumed fragments, whereas fish avoided white fragments. Although it is not yet clear how plastic coloration relates to the selectivity and feeding of freshwater fish, the visual skills at a species-specific level could plausibly explain why certain colors are attractive or deterrent to a particular fish species. This data set can be used as a screening tool that could help to understand the mechanisms underlying the patterns of plastic ingestion by fish, with special emphasis on the color of plastic particles. Future research on mechanisms MPs intake by fish, also providing a multi-species approach is highly recommended.

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Human head lice Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae) are ectoparasites that cause pediculosis, a global scale disease mainly found in school-age children. Previous works from our laboratory found nonanal, sulcatone, and geranylacetone as the main human scalp volatile components, and individually evaluated their attraction to head lice using an olfactometer. In this work, we compared how their blends at different concentrations attract head lice, and how their blended effect compares to the effect of isolated compounds. At the concentrations evaluated, individual components did not show attraction towards head lice, but a ternary mixture of them was attractive. Moreover, a solvent extract from the human head scalp was analyzed by GC-MS, finding that tetradecanoic acid, palmitic acid, oleic acid, palmitoleic acid, and squalene are the most abundant components. Attraction to these individual compounds at natural concentrations was tested by bioassays in a circular experimental arena. No attraction was observed when the components were tested individually, but when they were evaluated as a blend they attracted head lice. This work presents new information about how chemical signals are attractive at certain concentrations and proportions. This information could be used to better understand communication mechanisms in head lice and for the development of louse repellents.

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Computational simulation of colloidal systems make use of empirical interaction potentials that are founded in well-established theory. In this work, we have performed parallel tempering Monte Carlo (PTMC) simulations to calculate heat capacity and to assess structural transitions, which may occur in charged colloidal clusters whose effective interactions are described by a sum of pair potentials with attractive short-range and repulsive long-range components. Previous studies on these systems have shown that the global minimum structure varies from spherical-type shapes for small-size clusters to Bernal spiral and "beaded-necklace" shapes at intermediate and larger sizes, respectively. In order to study both structural transitions and dissociation, we have organized the structures appearing in the PTMC calculations by three sets according to their energy: (i) low-energy structures, including the global minimum; (ii) intermediate-energy "beaded-necklace" motifs; (iii) high-energy linear and branched structures that characterize the dissociative clusters. We observe that, depending on the cluster, either peaks or shoulders on the heat-capacity curve constitute thermodynamics signatures of dissociation and structural transitions. The dissociation occurs at T=0.20 for all studied clusters and it is characterized by the appearance of a significant number of linear structures, while the structural transitions corresponding to unrolling the Bernal spiral are quite dependent on the size of the colloidal system.

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In the study of the chemical communication of adults of the Melolonthidae family, bacteria have been observed in the epithelium of the genital chamber; possibly, bacteria are involved in the production of sex attractants in their hosts. Therefore, it is important to identify the volatile organic compounds from bacteria (VOCsB) released by these microorganisms and study the biological activity stimulated by VOBCs in adults of Melolonthidae. In this study, bacteria were isolated from the genital chamber of Cyclocephala lunulata and Cyclocephala barrerai, from which VOCsB were extracted using static headspace solid-phase microextraction (SHS-SPME) and dynamic headspace Super Q solid-phase extraction (DHS-SPE) and analyzed using gas chromatography-mass spectrometry. The effect of VOCsB on the hosts and conspecifics was evaluated utilizing an olfactometer and electroantennography (EAG). Two species of Enterobacteria were isolated from the genital chamber of each female species, and VOCsB derived from sulfur-containing compounds, alcohols, esters, and fatty acids were identified. An attraction response was observed in olfactometry studies, and antennal responses to VOCsB were confirmed in EAG bioassays. With these results, new perspectives on the relationship between these beetles and their bacteria emerge, in addition to establishing a basis for management programs in the future.

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The African parasitoids Cephalonomia stephanoderis Waterston (Bethylidae: Hymenoptera), Prorops nasuta Betrem (Bethylidae: Hymenoptera), and Phymastichus coffea LaSalle (Eulophidae: Hymenoptera) are biological control agents of the coffee berry borer (Coleoptera: Curculionidae). In this study, we investigated in laboratory the female behavioral responses of these parasitoids to 14 different wavelengths (340-670 nm) against a control (570 nm, yellow). When nonchooser females were included in the analysis, none parasitoids species showed a preference between 340, 350, 370, 460, 490, 520, 540, 590, 640, and 650 nm with respect to the control wavelength. In contrast, the three species of parasitoids were more attracted to wavelengths of 380, 400, and 420 nm than the control wavelength. Phymastichus coffea and P. nasuta were more attracted to the wavelength of 400 and 420 nm compared to C. stephanoderis. At 380 nm, P. coffea and C. stephanoderis wasps showed the higher responses in comparison to P. nasuta females. When nonchooser wasps were excluded from the analysis, we observed other differences among the parasitoid species. For instance, P. coffea were more attracted to 490-540 nm than to 570 nm, whereas the bethylids did not discriminate between 490-540 nm or 570 nm. Our results are discussed in relation to possible implications associated with the vision of these parasitoid species.

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Cancer is a genetic disease for which traditional treatments cause harmful side effects. After two decades of genomics technological breakthroughs, personalized medicine is being used to improve treatment outcomes and mitigate side effects. In mathematical modeling, it has been proposed that cancer matches an attractor in Waddington's epigenetic landscape. The use of Hopfield networks is an attractive modeling approach because it requires neither previous biological knowledge about protein-protein interactions nor kinetic parameters. In this report, Hopfield network modeling was used to analyze bulk RNA-Seq data of paired breast tumor and control samples from 70 patients. We characterized the control and tumor attractors with respect to their size and potential energy and correlated the Euclidean distances between the tumor samples and the control attractor with their corresponding clinical data. In addition, we developed a protocol that outlines the key genes involved in tumor state stability. We found that the tumor basin of attraction is larger than that of the control and that tumor samples are associated with a more substantial negative energy than control samples, which is in agreement with previous reports. Moreover, we found a negative correlation between the Euclidean distances from tumor samples to the control attractor and patient overall survival. The ascending order of each node's density in the weight matrix and the descending order of the number of patients that have the target active only in the tumor sample were the parameters that withdrew more tumor samples from the tumor basin of attraction with fewer gene inhibitions. The combinations of therapeutic targets were specific to each patient. We performed an initial validation through simulation of trastuzumab treatment effects in HER2+ breast cancer samples. For that, we built an energy landscape composed of single-cell and bulk RNA-Seq data from trastuzumab-treated and non-treated HER2+ samples. The trajectory from the non-treated bulk sample toward the treated bulk sample was inferred through the perturbation of differentially expressed genes between these samples. Among them, we characterized key genes involved in the trastuzumab response according to the literature.

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HYPOTHESIS: Colloids at fluid interfaces organize according to inter-particle interactions. The main contributions to an effective interaction potential are expected to be electrostatic dipole-dipole repulsion and capillary attraction due to fluid interface deformation. When these interactions are weak, a secondary minimum in the particle pair interaction potential is expected. EXPERIMENTS: Clean bare silica particles were deposited at an oil/water interface and their organization as well as dynamics were observed under a light microscope and analyzed in terms of radial distribution function and mean squared displacement. FINDINGS: Weak long-range competing interactions between colloids at an oil/water interface result in cluster formation. The clusters have a liquid-like structure and grow with increasing particle packing fraction. System 'ergodicity' suggests near-equilibrium assembly, which is confirmed by free particle dynamics outside the clusters. The interplay between dipole-dipole repulsion and capillary attraction responsible for the cluster formation is reflected in a secondary minimum of the effective interaction potential predicted theoretically but inaccessible experimentally from collective particle properties prior to this work.

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Diamides have been used worldwide to manage the diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), however some strains showed resistance to these molecules. Also, pheromone traps could be used to manage this pest, hence reducing the use of insecticides in the field. Resistant DBM strains may have biological disadvantages in comparison to susceptible strains in areas without sprays, including reduction in fitness or behavioral changes. Therefore, the aim of this study was to investigate whether DBM strains resistant to chlorantraniliprole showed adaptive costs that could alter male attraction to the sex pheromone, in comparison to susceptible strains in the laboratory and semi-field conditions. First, the LC1, LC10, LC25, and LC50 of DBM to chlorantraniliprole were established, which were 0.003, 0.005, 0.007, and 0.011 mg a.i. liter-1, and 5.88, 24.80, 57.22, and 144.87 mg a.i. liter-1 for the susceptible and resistant strains, respectively. Development and reproduction of DBM strains subjected to those concentrations were compared. Later, male response to the sex pheromone was investigated in a Y-tube in the laboratory and in a greenhouse to pheromone traps. Resistant DBM strain showed an adaptive cost in comparison to the susceptible strain that can result in a delay in population growth in the field when selection pressure is absent. Conversely, resistant males have no olfactory response alteration in comparison to susceptible males, consistently at 3 (P = 0.6848) and 7 days (P = 0.9140) after release, suggesting that pheromone traps continue to be a viable alternative to manage DBM in an IPM system.

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Dentre as modalidades de relacionamentos interpessoais, a amizade desponta como uma das mais significativas, considerando os valores e comportamentos associados ao que se espera em uma relação de amizade. O objetivo deste estudo foi identificar os elementos caracterizadores das representações sociais da amizade para universitários. Compôs a amostra 120 estudantes, de ambos os sexos, tendo sido utilizada uma entrevista semidiretiva para a coleta dos dados, complementada por questões de caracterização da amostra. As entrevistas foram organizadas em um corpus, submetido a uma Classificação Hierárquica Descendente, com auxílio do software IRaMuTeQ. Os resultados indicaram diferenças entre os sexos, sendo que o grupo feminino apresentou maior quantidade de elementos associados à amizade, enquanto a ênfase na amizade entre o sexo masculino se associa mais à confiança e companheirismo entre pares. Ressalta-se que ambos os sexos consideram a confiança e o companheirismo elementos igualmente importantes. Os dados permitem identificar padrões representacionais que influenciam nas expectativas e ações frente a comportamentos associados à amizade

Among the modalities of interpersonal relationships, friendship emerges as one of the most significant, considering the values and behaviors associated with what is expected in a relationship of friendship. The objective of this study was to identify the characterizing elements of the social representations of friendship for university students. The sample comprised 120 students, of both sexes, and a semidirectional interview was used to collect the data, complemented by questions of characterization of the sample. The interviews were organized in a corpus, submitted to a Hierarchical Descending Classification, with the aid of IRaMuTeQ software. The results indicated differences between the sexes, with the female group presenting a greater amount of elements associated with friendship, while the emphasis on friendship between males is associated more with confidence and companionship among peers. It is emphasized that both sexes consider trust and companionship equally important. The data allow us to identify representational patterns that influence expectations and actions in relation to behaviors associated with friendship

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O fenômeno das relações amorosas tem sido tema frequente nos discursos sociais, englobando valores, crenças e atitudes referentes às características associadas tanto ao parceiro ideal, quanto ao relacionamento amoroso ideal. Este estudo teve por objetivo identificar os elementos caracterizadores das representações sociais sobre relacionamentos amorosos, para universitários de ambos os sexos. Participaram 120 sujeitos, divididos igualmente por sexo, por meio de uma entrevista individual semi-estruturada, e analisadas com auxílio do software IRaMuTeQ. Verificou-se diferenças nos conteúdos representacionais entre homens e mulheres, em que o grupo feminino ancora seus valores em atribuições de natureza mais comportamentais do parceiro, como parceria, confiança, companheirismo e estabilidade, enquanto o grupo masculino ancora-se em atribuições mais objetivas, como atração física e sedução, por exemplos. Ressalta-se que ambos os sexos levantam os elementos amor, paixão e fidelidade. Os dados permitem comparar-se à estudos anteriores, verificando possíveis mudanças nos valores e crenças acerca de relacionamentos amorosos.

The phenomenon of love relationships has been a frequent theme in social discourses, encompassing values, beliefs and attitudes regarding the characteristics associated with both the ideal partner and the ideal love relationship. This all aimed to identify the characterizing elements of social representations about love relationships, for university students of both sexes. A total of 120 subjects, divided equally by sex, were interviewed using a semi-structured individual interview, and analyzed using IRaMuTeQ software. There were differences in the representational content between men and women, where the female group anchors their values in more behavioral attributions of the partner, such as partnership, confidence, companionship and stability, while the masculine group anchors itself in more objective attributions, as physical attraction and seduction, for example. It is emphasized that both sexes raise the elements love, passion and fidelity. The data allow comparison to previous studies, checking for possible changes in values and beliefs about love relationships.

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Color polymorphisms have been traditionally attributed to apostatic selection. The perception of color depends on the visual system of the observer. Theoretical models predict that differently perceived degrees of conspicuousness by two predator and prey species may cause the evolution of polymorphisms in the presence of anti-apostatic and apostatic selection. The spider Gasteracantha cancriformis (Araneidae) possesses several conspicuous color morphs. In orb-web spiders, the prey attraction hypothesis states that conspicuous colors are prey lures that increase spider foraging success via flower mimicry. Therefore, polymorphism could be maintained if each morph attracted a different prey species (multiple prey hypothesis) and each spider mimicked a different flower color (flower mimicry hypothesis). Conspicuous colors could be a warning signal to predators because of the spider's hard abdomen and spines. Multiple predators could perceive morphs differently and exert different degrees of selective pressures (multiple predator hypothesis). We explored these 3 hypotheses using reflectance data and color vision modeling to estimate the chromatic and achromatic contrast of G. cancriformis morphs as perceived by several potential prey and predator taxa. Our results revealed that individual taxa perceive the conspicuousness of morphs differently. Therefore, the multiple prey hypothesis and, in part, the multiple predator hypothesis may explain the evolution of color polymorphism in G. cancriformis, even in the presence of anti-apostatic selection. The flower mimicry hypothesis received support by color metrics, but not by color vision models. Other parameters not evaluated by color vision models could also affect the perception of morphs and influence morph survival and polymorphism stability.

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Ecological resilience refers to the ability of a system to retain its state when subject to state variables perturbations or parameter changes. While understanding and quantifying resilience is crucial to anticipate the possible regime shifts, characterizing the influence of the system parameters on resilience is the first step toward controlling the system to avoid undesirable critical transitions. In this paper, we apply tools of qualitative theory of differential equations to study the resilience of competing populations as modeled by the classical Lotka-Volterra system. Within the high interspecific competition regime, such model exhibits bistability, and the boundary between the basins of attraction corresponding to exclusive survival of each population is the stable manifold of a saddle point. Studying such manifold and its behavior in terms of the model parameters, we characterized the populations resilience: While increasing competitiveness leads to higher resilience, it is not always the case with respect to reproduction. Within a pioneering context where both populations initiate with few individuals, increasing reproduction of one population leads to an increase in its resilience; however, within an environment previously dominated by one population and then invaded by the other, an increase in the resilience of a population is obtained by decreasing its reproduction rate. Besides providing interesting insights for the dynamics of competing populations, this work brings near to each other the concepts of ecological resilience and the methods of differential equations and stimulates the development and application of new tools for ecological resilience.

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OBJECTIVE: To examine how sexual identity, romantic attraction, and sexual behavior co-relate for cisgender adolescents. STUDY DESIGN: The Teen Health and Technology survey was a cross-sectional, self-report online survey. More than 5000 youth between 13 and 18 years of age were randomly recruited through Harris Panel OnLine's panel as well as outreach by GLSEN to over-recruit lesbian, gay, bisexual, and other sexual minority youth. Data were collected between 2010 and 2011. Analyses were conducted in 2018 and restricted to cisgender youth. RESULTS: Overall, romantic attraction and sexual behavior most closely mapped each other. The greatest discordance was noted between sexual identity and romantic attraction. For example, 59% of girls and 16% of boys who identified with a nonheterosexual identity reported that at least 1 of their 2 most recent sexual partners was a different gender. Nine percent of heterosexually-identified girls and 3% of heterosexually-identified boys reported romantic attraction to the same sex, and 6% and 7% of heterosexually-identified girls and boys, respectively, reported that at least 1 of their 2 most recent sexual partners was the same gender. CONCLUSIONS: Treating romantic attraction, sexual identity, and sexual behavior as synonymous assumes a unidimensionality that is unsupported by the data. Pediatricians and others working with youth, including researchers, should be mindful not to assume identity on the basis of behavior. Researchers should be clear and purposeful about how they are operationalizing "sexual minority" and how it may affect the composition of their study population. Healthy sexuality and risk reduction programs need to acknowledge that adolescents with a particular sexual identity may have romantic attractions, and even sexual encounters, with people who fall outside of that identity.

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The objectives of the study are to understand how naïve beetles disperse after emerging as an adult in a homogeneous resource patch. We compared the movement of adult male and female Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) using a laboratory and a field-collected strain during the first 2 d after their emergence from the wheat kernel in which they developed. We first asked if naïve male and female beetles show any innate orientation pattern. Males showed an upward orientation bias during the first day, but not in the second, whereas females had a random pattern of orientation in both days of evaluation. No significant differences were observed between the two strains. Given that males release an aggregation pheromone, we next asked if the upward movement of males improved their ability to be found by a naïve female. The presence of a male, whether above or below a newly emerged female, changed the females' movement direction from random to bias towards the male. In contrast, free-walking males exhibited the same upward movement bias on the first day regardless of the position of the caged male. Only on the second day did male movement change to the opposite direction of the caged male. Here, we report differences between males and females' movement orientation strategies and their response to males producing aggregation pheromone within the grain mass. Our data may improve our understanding of pheromone attraction and help us to develop better monitoring and control tools.

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Abstract Ivermectin (IVM) is widely used for parasite control in livestock in the tropics. Residual IVM in feces conserves its insecticide activity for weeks and can harm dung beetle (DB) species. Attraction to the feces of IVM-treated cattle was tested using the DB species Onthophagus landolti (Harold) and Canthon indigaceus chevrolati (Harold) as models. Experiments were done under controlled laboratory conditions, semi-controlled field conditions and uncontrolled field conditions. Olfactometers were used in the controlled and semi-controlled trials. The control treatment was baited IVM-free feces, and the experimental treatments were the feces of cattle treated with 1 % IVM (subcutaneous administration; single, 0.2 mg/kg bw dosage) and collected at 5, 14, 21 and 28 days post-treatment. The uncontrolled field trial involved pitfall traps baited with IVM-free feces or feces from IVM-treated cattle collected five days post-treatment. Under controlled and semi-controlled conditions, the feces of IVM-treated cattle (at 5, 14, 21 or 28 days post-treatment) attracted more O. landolti and C. i. chevrolati individuals than IVM-free feces (P < 0.05). The same response occurred under uncontrolled conditions. This clear attraction for IVM-containing cattle feces by the studied DB species highlights that incorrect IVM use may pose a risk to DB communities in cattle production systems.(AU)

Resumen La ivermectina (IVM) es ampliamente utilizada para el control de parásitos en el ganado en los trópicos. La IVM residual en las heces conserva su actividad insecticida durante semanas y puede dañar diversas especies de escarabajos estercoleros. La atracción a las heces del ganado tratado con IVM se probó usando a las especies Onthophagus landolti (Harold) y Canthon indigaceus chevrolati (Harold) como modelos de estudio. Los experimentos se realizaron bajo condiciones de laboratorio controladas, condiciones de campo semicontroladas y condiciones de campo no controladas. Se utilizaron olfatómetros en los ensayos controlados y semicontrolados. El tratamiento de control consistió en heces exentas de IVM, y los tratamientos experimentales fueron heces de ganado tratado con IVM al 1 % (administración subcutánea, dosis única, 0.2 mg / kg pv) las cuales se recogieron a los 5, 14, 21 y 28 días después del tratamiento al ganado. El ensayo de campo no controlado incluyó trampas de caída libre o pitfall cebadas con heces libres de IVM y con heces de ganado tratado con IVM recogido cinco días después del tratamiento. En condiciones controladas y semicontroladas, las heces del ganado tratado con IVM (a los 5, 14, 21 y 28 días después del tratamiento) atrajeron más individuos O. landolti yC. i. chevrolati que las heces sin IVM (P < 0.05). La misma respuesta ocurrió bajo condiciones no controladas. Esta clara atracción a las heces de ganado que contienen IVM por las especies estudiadas pone de relieve que el uso incorrecto de IVM puede plantear un riesgo para las comunidades de escarabajos estercoleros en los sistemas de producción ganadera.(AU)

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Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography-mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.