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BACKGROUND: Aedes aegypti is the primary mosquito vector for several arboviruses, such as dengue, chikungunya and Zika viruses, which cause frequent outbreaks of human disease in tropical and subtropical regions. Control of these outbreaks relies on vector control, commonly in the form of insecticide sprays that target adult female mosquitoes. However, the spatial coverage and frequency of sprays needed to optimize effectiveness are unclear. In this study, we characterize the effect of ultra-low-volume (ULV) indoor spraying of pyrethroid insecticides on Ae. aegypti abundance within households. We also evaluate the effects of spray events during recent time periods or in neighboring households. Improved understanding of the duration and distance of the impact of a spray intervention on Ae. aegypti populations can inform vector control interventions, in addition to modeling efforts that contrast vector control strategies. METHODS: This project analyzes data from two large-scale experiments that involved six cycles of indoor pyrethroid spray applications in 2 years in the Amazonian city of Iquitos, Peru. We developed spatial multi-level models to disentangle the reduction in Ae. aegypti abundance that resulted from (i) recent ULV treatment within households and (ii) ULV treatment of adjacent or nearby households. We compared fits of models across a range of candidate weighting schemes for the spray effect, based on different temporal and spatial decay functions to understand lagged ULV effects. RESULTS: Our results suggested that the reduction of Ae. aegypti in a household was mainly due to spray events occurring within the same household, with no additional effect of sprays that occurred in neighboring households. Effectiveness of a spray intervention should be measured based on time since the most recent spray event, as we found no cumulative effect of sequential sprays. Based on our model, we estimated the spray effect is reduced by 50% approximately 28 days after the spray event. CONCLUSIONS: The reduction of Ae. aegypti in a household was mainly determined by the number of days since the last spray intervention in that same household, highlighting the importance of spray coverage in high-risk areas with a spray frequency determined by local viral transmission dynamics.

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Insects are under constant selective pressure, which has resulted in adaptations to novel niches such as crops. This is the case of the pest Melanaphis sacchari, the sugarcane aphid, native to Africa and currently spreading worldwide. The aphid undergoes successful parthenogenesis, causing important damage to a variety of crops and leading to important economic losses for farmers. A natural M. sacchari population grown in sorghum was studied to identify its microbiome through the sequencing of its 16S rDNA metagenome. A high proportion of Proteobacteria, followed by Firmicutes, Bacteroidetes, and Actinobacteria, was observed. We also detected Wolbachia, which correlates with the asexual reproduction of its host. M. sacchari was challenged in a bioassay with the antibiotics oxytetracycline and streptomycin, resulting in a dose-dependent decay of its survival rate. The possibility of controlling this pest by altering its microbiota is proposed.

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BACKGROUND: The application of allyl isothiocyanate (AITC) has been proposed as an alternative to control stored-grain insects. However, AITC is a compound with a low diffusion coefficient, making its distribution throughout the grain mass difficult. Therefore, the objective of the present study was to evaluate the effectiveness of AITC applied in systems with or without recirculation for controlling Sitophilus zeamais (Mots. 1855) (Coleoptera: Curculionidae), Rhyzopertha dominica (Fabr.) (Coleoptera: Bostrichidae), and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) infesting a corn grain mass. The assays used a polyvinyl chloride (PVC) prototype, dimensioned 1.60 m in length, 0.30 m in diameter, and a static capacity of 60 kg of grains. AITC toxicity to insects was evaluated at the base, 0.5 m from the base, and top of the grain column (1.0 m). Different concentrations of AITC were tested for an exposure period of 48 h. RESULTS: In the system without AITC recirculation, insect mortality was verified only at the base of the grain column. However, insect mortality was considered uniform at the different positions of the column when the AITC recirculation system was adopted. In this system, there was also a marked reduction in the instantaneous population growth rate of S. zeamais, T. castaneum, and R. dominica, and a decrease in the dry matter loss of the grains, when the AITC concentrations were increased. CONCLUSION: AITC recirculation proved to be a viable strategy for protecting grains against the species S. zeamais, R. dominica, and T. castaneum. AITC fumigation ultimately did not cause changes in grain quality. © 2023 Society of Chemical Industry.

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Schinus terebinthifolius, Raddi, has been extensively studied due to its anti-inflammatory and antibiotic properties. S. terebinthifolius was also toxic to some insects, however little has been explored about the nature of its insecticide compounds or the toxicity of this plant to insect species. In this work, we investigate the toxicity of S. terebinthifolius seed flour against the insect C. maculatus. S. terebinthifolius seed flour interfered with the post hatch development of the C. maculatus larvae, decreasing larval survival, mass and length. Using DEAE-cellulose chromatography, five protein fractions were isolated, a non-retained fraction (NRF) and four retained fractions, eluted with 0.25, 0.5, 0.7 and 1.0 M NaCl. Proteins with varying molecular masses were observed in all fractions. The majority protein bands were identified by mass spectrometry analysis and among the main identified proteins are 11S globulins (such glycinin), lipoxygenase, chitinases, 7S globulins (vicilins, canavalin and ß conglycinin), annexin, catalase and sucrose binding protein. All DEAE-protein fractions were toxic to the insect, interfering with the post hatch larval development and survival. Decreases greater than 90% were observed in the larval mass and length at 20 days after oviposition (DAO) for larvae raised on diet containing 0.5% of some fractions. Alterations in the level of proteins, glucose and in the activity of the enzymes lipases and cysteine proteases were also detected in these larvae. Our results show that seeds of S. terebinthifolius have an arsenal of toxic proteins with potential for the control of the insect C. maculatus.

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The study aimed to develop a multiplex qPCR to detect Leishmania infantum load in different sandfly sample settings using Leishmania kDNA and sandfly vacuolar ATPase (VATP) subunit C as internal control gene. The amplification of Lutzomyia longipalpis VATP gene was evaluated together with Leishmania infantum kDNA in a multiplex reaction. The concentration of VATP gene oligonucleotides was adjusted until no statistically significant difference was observed between all multiplex standard curves and singleplex curves, that is, only kDNA amplification. Limit of detection (LoD) was measured using a probit model and a cut-off defined by receiver operating characteristic analysis. Limit of quantification (LoQ) was assessed by a linear model using the coefficient of variation threshold of 25%. After assuring VATP gene amplification, its primer-probe concentrations were best at 100 nM/10 nM, respectively. The cut-off Cq value for L. infantum kDNA was defined as 35.46 with 100% of sensitivity and specificity. A total of 95% LoD was determined to be of 0.162 parasites while LoQ was 5.858. Our VATP/kDNA multiplex qPCR assay shows that it can be used to evaluate both DNA integrity and determine L. infantum load in L. longipalpis even for low yielded samples, that is, individual midguts.

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The harmful effects caused by the use of toxic substances in agriculture have led to the development of alternative solutions, and researchers have focused on understanding the effectiveness and potential of plant extracts in agriculture. The aim of this systematic review was to understand the situation of research and scientific dissemination, as well as how current science has approached the use of plant extracts in agriculture, especially in seed applications. There is potential on the use of plant extracts in agriculture, demonstrated by a high number of publications over the last ten years, especially in the years 2018, 2019 and 2020, and Brazil stands out as the main country on this research area. Control of phytopathogenic microorganisms, insect control, biostimulant effect, resistance induction and herbicide effect have been the main themes explored for use in agriculture. The direct application of plant extracts is centered on plants and seeds, being this latter mainly focused on the control of phytopathogenic organisms and biostimulating effect.

Em resposta aos efeitos nocivos da utilização de substâncias toxicas na agricultura, a ciência tem avançado no desenvolvimento de soluções alternativas, visando compreender a eficácia e o potencial de extratos vegetais na agricultura. Objetivou-se com esta revisão sistematizada compreender a situação da pesquisa e divulgação científica, bem como a maneira que a ciência atual tem abordado o uso de extratos vegetais na agricultura, especialmente na aplicação em sementes. O uso de extratos vegetais na agricultura tem potencial demonstrado pelo elevado número de publicações nos últimos dez anos, com destaque para os anos de 2018, 2019 e 2020, sendo o Brasil o país de maior produção de trabalhos voltados à essa área de estudo. Os temas controle de microrganismos fitopatogênicos, controle de insetos, efeito bioestimulante, indução de resistência e efeito herbicida tem sido os principais temas explorados para uso na agricultura. A aplicação de extratos vegetais é centrada principalmente em organismos fitopatogênicos associados a plantas e sementes, sendo que, para a aplicação em sementes, o foco está no controle de organismos fitopatogênicos e efeito de promoção de crescimento.

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Silver nanoparticles are widely used in the biomedical and agri-food fields due to their versatility. The use of biological methods for the synthesis of silver nanoparticles has increased considerably due to their feasibility and high biocompatibility. In general, microorganisms have been widely explored for the production of silver nanoparticles for several applications. The objective of this work was to evaluate the use of entomopathogenic fungi for the biological synthesis of silver nanoparticles, in comparison to the use of other filamentous fungi, and the possibility of using these nanoparticles as antimicrobial agents and for the control of insect pests. In addition, the in vitro methods commonly used to assess the toxicity of these materials are discussed. Several species of filamentous fungi are known to have the ability to form silver nanoparticles, but few studies have been conducted on the potential of entomopathogenic fungi to produce these materials. The investigation of the toxicity of silver nanoparticles is usually carried out in vitro through cytotoxicity/genotoxicity analyses, using well-established methodologies, such as MTT and comet assays, respectively. The use of silver nanoparticles obtained through entomopathogenic fungi against insects is mainly focused on mosquitoes that transmit diseases to humans, with satisfactory results regarding mortality estimates. Entomopathogenic fungi can be employed in the synthesis of silver nanoparticles for potential use in insect control, but there is a need to expand studies on toxicity so to enable their use also in insect control in agriculture.

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Vigna unguiculata is an important source of proteins and energy for humans and animals. However, postharvest losses caused by Callosobruchus maculatus can reach from 20 to 100% of stored seeds. In this study, the insecticide potential of compounds extracted from Himatanthus drasticus latex was assessed. The latex was extracted with ethanol (70%) and then partitioned through sequential use of hexane and chloroform. These fractions were investigated by chromatography to determine their chemical composition. Plumieride, identified in a hydroalcoholic subfraction, was tested for insecticidal activity against C. maculatus. The ethanolic fraction (LC50 = 0.109; LC90 = 0.106%) and the plumieride (LC50 = 0.166; LC90 = 0.167%) were lethal to larvae. Plumieride (0.25%) delayed larval development, and mortality reached 100%. Its inhibitory action on intestinal α-amylase from larvae was higher (89.12%) than that of acarbose (63.82%). Plumieride (0.1%) inhibited the enzyme α-amylase in vivo in the larval intestine. This result was confirmed by a zymogram test performed by SDS-PAGE when the enzyme electrophoresed on gel copolymerized with starch. When spread on seeds, the hydroalcoholic fraction (1.0%) reduced infestation. The loss of seed mass was 5.26% compared to the control (44.97%). The results confirm the effect of latex compounds in protecting stored seeds against weevil infestation.

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The lesser grain borer, Rhyzopertha dominica, is a coleopteran pest of stored grains and is mainly controlled by phosphine fumigation, but the increase in phosphine-resistant populations threatens efficacy. Some phosphine-resistant insects have reduced respiration, and thus studying the mitochondrial genome may provide additional information regarding resistance. Genomic DNA from an inbred laboratory strain of R. dominica was extracted and sequenced with both short (Illumina) and long (Pacific Biosciences) read technologies for whole genome sequence assembly and annotation. Short read sequences were assembled and annotated by open software to identify mitochondrial sequences, and the assembled sequence was manually annotated and verified by long read sequences. The mitochondrial genome sequence for R. dominica had a total length of 15,724 bp and encoded 22 trna genes, 2 rRNA genes, 13 protein coding genes (7 nad subunits, 3 cox, 2 atp, and 1 cytB), flanked by a long control region. We compared our predicted mitochondrial genome to that of another from a R. dominica strain from Jingziguan (China). While there was mostly agreement between the two assemblies, key differences will be further examined to determine if mutations in populations are related to insecticide control pressure, mainly that of phosphine. Differences in sequence data, assembly, and annotation also may result in different genome interpretations.

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Las mariposas (lepidópteros) pueden ocasionar molestias en algunas ocasiones, Hylesia metabuses una mariposa de hábitos nocturnos, caracterizada por presentar pelos que se desprenden durante el vuelo causando dermatitis y diversas reacciones alérgicas (lepidopterismo) en la población. En Venezuela,las invasiones cíclicas de H. metabus en nororiente del país ocasionan un problema de salud pública, requiriendo mantener la vigilancia para orientar labores de control. En este trabajo se realizó una descripción de las actividades para la vigilancia epidemiológica de H. metabus y del lepidopterismo en el estado Sucre. A través de revisión documental, se estudiaron 154 documentos referentes a la vigilancia de H. metabus y del lepidopterismo, emitidos por el Ministerio del Poder Popular para la Salud. Se evidenció una definición clara y precisa de evento, las acciones para el monitoreo de las fases evolutivas de H. metabus se encuentran bien delimitadas; sin embargo, las actividades para el monitoreo de los casos de lepidopterismo no están claramente establecidas. Se observó una adecuada recolección y flujo de información referente alas fases evolutivas de la mariposa, pero poca recolección de datos referentes a los casos de lepidopterismo. El mecanismo del flujo de información estuvo basado en comunicaciones e informes técnicos eventuales y solamente en el nivel estadal de salud se realizó actividades de consolidación y análisis de datos. En conclusión, se encuentran claramente definidas las actividades para el monitoreo de las fases evolutivas de la mariposa, pero deficiencia en la vigilancia del lepidopterismo. Se observan debilidades para la vigilancia epidemiológica de H. metabus(AU)

Butterflies (Lepidoptera) can sometimes cause discomfort, Hylesia metabus is a nocturnal butterfly, characterized by hair shedding during flight causing dermatitis and various allergic reactions (Lepidopterism) in the population. In Venezuela, cyclical invasions of H. metabus in the northeast of the country cause a public health problem, requiring vigilance to guide control efforts. In this work, a description of the activities for the epidemiological surveillance of H. metabus and lepidopterism in Sucre state was made. Through a documentary review, 154 documents referring to the surveillance of H. metabus and lepidopterism, issued by the Ministry of Popular Power for Health, were studied. A clear and precise definition of the event was evidenced, the actions for monitoring the evolutionary phases of H. metabus are well defined; however, activities for the monitoring of lepidopterism cases are not clearly established. There was an adequate collection and flow of information regarding the evolutionary phases of the butterfly, but little data collection regarding the cases of lepidopterism. The information flow mechanism was based on communications and eventual technical reports and only at the state health level were data consolidation and analysis activities carried out. In conclusion, the activities for monitoring the evolutionary phases of the butterfly are clearly defined, but there is a deficiency in the surveillance of lepidopterism. Weaknesses are observed for the epidemiological surveillance of H. metabus(AU)

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The lesser mealworm control is mostly made by insecticides, as the association of chlorpyrifos, cypermethrin and citronellal. The traditional insecticide application method (TRADM) depends on many liters of water and, with the objective of reducing water consumption, the aim was to compare TRADM with atomizer-equipment method (ATOMM). Four and three houses from farm A and B were used, respectively. Houses 1, 3 and 7 were treated with TRADM (1 liter of insecticide diluted in 500 liters of water) and houses 2, 4, 5 and 6 with ATOMM (1 liter of insecticide diluted in 9 liters of water). Twenty-four hours before and 30 (for farm A) and 45 days (for farm B) after the insecticide application, the number of insects was counted in each house (using 18 mapped traps/house). Farms were not considered different (p>0.05) and comparison was made between the houses. Houses were different (p<0.001) in the pre-treatment count, but they were equal in the second count (p=0.97). The insecticide application increased the number of traps without any insect (p<0.0001). In conclusion, the application method of chlorpyrifos, cypermethrin, and citronellal insecticide using atomizer equipment presented similar results than using the traditional application method. Both methods were effective in reducing the infestation of all houses, not making any difference if the dilution of the product was in 500 liters or in 9 liters of water; thus, it is possible to spend less water to run this management.

O controle do cascudinho é realizado principalmente por inseticidas, como a associação entre clorpirifos, cipermetrina e citronelal. O método tradicional de aplicação do inseticida (TRADM) depende de grande volume de água para a diluição e, visando à redução do uso de água, o estudo objetivou comparar TRADM com o método utilizando atomizador (ATOMM). Quatro galpões da propriedade A e três da B foram utilizados. Os galpões 1, 3 e 7 foram tratados com TRADM (1 litro inseticida:500 litros de água) e os galpões 2, 4, 5 e 6 tratados utilizando ATOMM (1 litro de inseticida:9 litros de água). Vinte e quatro horas antes e 30 (para A) e 45 dias (para B) após a aplicação foi realizada a contagem de cascudinhos em cada galpão (18 iscas mapeadas/galpão). Não houve diferença (p>0,05) entre as propriedades e os galpões foram considerados nas comparações. Estes diferiram quanto à contagem pré-tratamento (p<0,001), mas não diferiram na contagem pós-tratamento (p=0,97). A aplicação do inseticida aumentou o número de iscas sem insetos (p<0,0001). Concluindo, a aplicação do inseticida a base de clorpirifos, cipermetrina e citronelal usando atomizador apresentou resultado semelhante ao do método tradicional. Ambos os métodos são efetivos para reduzir a infestação de todos os galpões, não fazendo diferença se a diluição do produto foi realizada em 500 ou 9 litros de água; dessa forma, é possível gastar menor quantidade de água para realizar esse manejo.

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The lesser mealworm control is mostly made by insecticides, as the association of chlorpyrifos, cypermethrin and citronellal. The traditional insecticide application method (TRADM) depends on many liters of water and, with the objective of reducing water consumption, the aim was to compare TRADM with atomizer-equipment method (ATOMM). Four and three houses from farm A and B were used, respectively. Houses 1, 3 and 7 were treated with TRADM (1 liter of insecticide diluted in 500 liters of water) and houses 2, 4, 5 and 6 with ATOMM (1 liter of insecticide diluted in 9 liters of water). Twenty-four hours before and 30 (for farm A) and 45 days (for farm B) after the insecticide application, the number of insects was counted in each house (using 18 mapped traps/house). Farms were not considered different (p>0.05) and comparison was made between the houses. Houses were different (p<0.001) in the pre-treatment count, but they were equal in the second count (p=0.97). The insecticide application increased the number of traps without any insect (p<0.0001). In conclusion, the application method of chlorpyrifos, cypermethrin, and citronellal insecticide using atomizer equipment presented similar results than using the traditional application method. Both methods were effective in reducing the infestation of all houses, not making any difference if the dilution of the product was in 500 liters or in 9 liters of water; thus, it is possible to spend less water to run this management.(AU)

O controle do cascudinho é realizado principalmente por inseticidas, como a associação entre clorpirifos, cipermetrina e citronelal. O método tradicional de aplicação do inseticida (TRADM) depende de grande volume de água para a diluição e, visando à redução do uso de água, o estudo objetivou comparar TRADM com o método utilizando atomizador (ATOMM). Quatro galpões da propriedade A e três da B foram utilizados. Os galpões 1, 3 e 7 foram tratados com TRADM (1 litro inseticida:500 litros de água) e os galpões 2, 4, 5 e 6 tratados utilizando ATOMM (1 litro de inseticida:9 litros de água). Vinte e quatro horas antes e 30 (para A) e 45 dias (para B) após a aplicação foi realizada a contagem de cascudinhos em cada galpão (18 iscas mapeadas/galpão). Não houve diferença (p>0,05) entre as propriedades e os galpões foram considerados nas comparações. Estes diferiram quanto à contagem pré-tratamento (p<0,001), mas não diferiram na contagem pós-tratamento (p=0,97). A aplicação do inseticida aumentou o número de iscas sem insetos (p<0,0001). Concluindo, a aplicação do inseticida a base de clorpirifos, cipermetrina e citronelal usando atomizador apresentou resultado semelhante ao do método tradicional. Ambos os métodos são efetivos para reduzir a infestação de todos os galpões, não fazendo diferença se a diluição do produto foi realizada em 500 ou 9 litros de água; dessa forma, é possível gastar menor quantidade de água para realizar esse manejo.(AU)

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Objetivo: Foi realizado estudo transversal com objetivo de descrever as práticas de uso de inseticidas utilizados no controle dos vetores no ambiente doméstico. Material e Métodos: Foram aplicados questionários em 122 residências no município de Niterói, na Região Oceânica em 2010. Destes, 61 foram realizados em condomínio de classe média alta e 61 em Comunidade de baixa renda. Resultados: Os resultados demonstraram que 92% do grupo Condomínio e 77,7% do grupo Colônia de Pescadores usam inseticidas. Em relação aos cuidados com manuseio de inseticidas, 62,2% dos entrevistados do Grupo Condomínio e 35,6% dos entrevistados do Grupo Colônia de Pescadores, disseram que não tomavam nenhum cuidado ao usar estes produtos. Os dados sugerem que pessoas com menor escolaridade têm mais chances de não usar adequadamente os inseticidas que são produtos potencialmente tóxicos. Conclusão: Conclui-se que aspectos relacionados ao nível educacional e local de moradia estão relacionados ao uso mais adequado de inseticidas domésticos. (AU)

Objetive: Cross-sectional study was performed in order to describe practices with insecticides used in the control of insect vectors in the household. Methods: Questionnaires were applied in 154 households in Niterói City, in the Oceanic Region of Rio de Janeiro ́s State, in 2010. Of these, 77 were performed in upper middle class Apartament Complexes and 61 in the low-income community both in the Oceanic Region of Niterói. Results:The results showed that 92% of Apartment Complexes and 77.7% of Fishermen Colony use insecticides. Regarding care handling insecticides, 62.2% of the respondents of the Apartment Complex Group and 35.6% of the respondents from the Fishermen Colony Group said they were not taking any care when using these products. Data suggests that people with low education are more likely to not properly use potentially toxic pesticides. Conclusion: We conclude that aspects related to educational level and residential location are associated to more appropriate use of household insecticides. (AU)

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BACKGROUND: The Spodoptera cosmioides (Walker, 1858) population has increased in Bacillus thuringiensis Berliner (Bt) soybean crops in Argentina. As there are no registered products for its control, the recommended insecticides for S. frugiperda are used. The aim of this study was therefore to determine the lethal concentration (LC) of chlorantraniliprole and its sublethal effects on the biological and reproductive functions of S. cosmioides, an emerging soybean pest in Argentina. RESULTS: An ingestion toxicity bioassay showed that chlorantraniliprole was active against larvae of the second instar, and after 48 h of exposure LC50 was 0.054 µg mL-1 H2 O. In the study of sublethal effect, chlorantraniliprole induced changes in the life cycle of exposed S. cosmioides, which required more time to complete all stages of development (larval, pupal and adult stages). Pupal weight was also higher in larvae exposed to sublethal concentrations of chlorantraniliprole. Adult fecundity was decreased: the number of eggs laid by each adult female moth, as compared with control females, was two (LC15 ) and eight (LC30 ) times lower. CONCLUSION: These results indicate that chlorantraniliprole has toxicity against S. cosmioides larvae. Sublethal effects on the biological and reproductive performance of this species can help optimize integrated pest management programs. © 2018 Society of Chemical Industry.

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Botanical repellents represent one of the main ways of reducing the use of synthetic pesticides and the contamination of soil and hydric resources. However, the poor stability and rapid degradation of these compounds in the environment hinder their effective application in the field. Zein nanoparticles can be used as eco-friendly carrier systems to protect these substances against premature degradation, provide desirable release characteristics, and reduce toxicity in the environment and to humans. In this study, we describe the preparation and characterization of zein nanoparticles loaded with the main constituents of the essential oil of citronella (geraniol and R-citronellal). The phytotoxicity, cytotoxicity, and insect activity of the nanoparticles toward target and nontarget organisms were also evaluated. The botanical formulations showed high encapsulation efficiency (>90%) in the nanoparticles, good physicochemical stability, and effective protection of the repellents against UV degradation. Cytotoxicity and phytotoxicity assays showed that encapsulation of the botanical repellents decreased their toxicity. Repellent activity tests showed that nanoparticles containing the botanical repellents were highly repellent against the Tetranychus urticae Koch mite. This nanotechnological formulation offers a new option for the effective use of botanical repellents in agriculture, reducing toxicity, protecting against premature degradation, and providing effective pest control.

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Crop protection is the basis of plant production and food security. Additionally, there are many efforts focused on increasing defensive mechanisms in order to avoid the damaging effects of insects, which still represent significant losses worldwide. Plants have naturally evolved different mechanisms to discourage herbivory, including chemical barriers such as the induction of defensive proteins and secondary metabolites, some of which have a historical link with bio-farming practices and others that are yet to be used. In the context of global concern regarding health and environmental impacts, which has been translated into political action and restrictions on the use of synthetic pesticides, this review deals with a description of some historical commercial phytochemicals and promising proteinaceous compounds that plants may modulate to defeat insect attacks. We present a broader outlook on molecular structure and mechanisms of action while we discuss possible tools to achieve effective methods for the biological control of pests, either by the formulation of products or by the development of new plant varieties with enhanced chemical defenses.

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Jaburetox is a recombinant peptide derived from a Canavalia ensiformis urease that presents toxic effects upon several species of insects, phytopathogenic fungi and yeasts of medical importance. So far, no toxicity of Jaburetox to mammals has been shown. Previous reports have identified biochemical targets of this toxic peptide in insect models, although its mechanism of action is not completely understood. In this work, we aimed to characterize the effects of Jaburetox in hemolymphatic insect cells. For this purpose, the model insect and Chagas' disease vector Rhodnius prolixus was used. In vivo and in vitro experiments indicated that Jaburetox interacts with a subset of hemocytes and it can be found in various subcellular compartments. In insects injected with Jaburetox there was an increase in the gene expression of the enzymes UDP-N-acetylglucosamine pyrophosphorylase (UAP), chitin synthase and nitric oxide synthase (NOS). Nevertheless, the expression of NOS protein, the enzyme activities of UAP and acid phosphatase (a possible link between UAP and NOS) as well as the phosphorylation state of proteins remained unchanged upon the in vivo Jaburetox treatment. Nitric oxide (NO) imaging using fluorescent probes showed that Jaburetox augmented NO production in the hemocyte aggregates when compared to controls. Even though Jaburetox activated the hemocytes, as demonstrated by wheat germ agglutinin binding assays, the peptide did not lead to an increase of their phagocytic behavior. Taken together, these findings contribute to our understanding of toxic effects of Jaburetox, a peptide with biotechnological applications and a prospective tool for rational insect control.

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Abstract INTRODUCTION: This study analyzed blackfly awareness and perceptions of health education practices for blackfly control among vulnerable populations in Brazil. METHODS: An exploratory descriptive quantitative research analysis was performed to investigate and analyze the awareness of and potential participation in blackfly control measures by vulnerable populations. RESULTS: Countryside resident participants (n = 24/38; 63.2% of the total sample) reported that blackflies were an obstacle to the performance of their work activities. CONCLUSIONS: Blackflies are a public health problem, and actions for blackfly control have been carried out without social participation or educational health practices that involve proper community knowledge.

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Major emergency efforts are being mounted for each vector-borne disease epidemiological crisis anew, while knowledge about the biology of arthropods vectors is dwindling slowly but continuously, as is the number of field entomologists. The discrepancy between the rates of production of knowledge and its use and need for solving crises is widening, in particular due to the highly differing time spans of the two concurrent processes. A worldwide web based search using multiple key words and search engines of onsite and online courses in English, Spanish, Portuguese, French, Italian and German concerned with the biology of vectors identified over 140 courses. They are geographically and thematically scattered, the vast majority of them are on-site, with very few courses using the latest massive open online course (MOOC) powerfulness. Over two third of them is given in English and Western Africa is particularity poorly represented. The taxonomic groups covered are highly unbalanced towards mosquitoes. A worldwide unique portal to guide students of all grades and levels of expertise, in particular those in remote locations, is badly needed. This is the objective a new activity supported by the Special Programme for Research and Training in Tropical Diseases (TDR).

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Spodoptera frugiperda (SMITH, 1797) (Lepidoptera: Noctuidae) affects diverse crops of great economic interest, for instance, it can cause severe yield losses in maize, rice and sorghum. In this study, a selection and characterization of Bacillus thuringiensis (BERLINER, 1911) isolates with a high insecticidal activity against S. frugiperda was performed. Fifty-two crystal-forming B. thuringiensis isolates that were identified from 3384 Bacillus-like colonies were examined and screened by PCR for the presence cry genes (cry1, cry1Aa, cry1Ab, cry1Ac, cry1D, cry2 and cry2Ab). Four isolates that showed high toxicity towards S. frugiperda were shown to harbor cry2 genes. The crystals were analyzed by electron microscopy and showed bipyramidal and cuboidal shapes. Furthermore, these four isolates had lethal concentration (LC50) values of 44.5 ng/cm2 (SUFT01), 74.0 ng/cm2 (SUFT02), 89.0 ng/cm2 (SUFT03) and 108 ng/cm2 (SUFT 04) to neonate S. frugiperda larvae. An ultrastructural analysis of midgut cells from S. frugiperda incubated with the SUFT01 spore-crystal complex showed disruptions in cellular integrity and in the microvilli of the midgut columnar cells. The isolates characterized in this work are good candidates for the control of S. frugiperda, and could be used for the formulation of new bioinsecticides.

Spodoptera frugiperda (SMITH, 1797) (Lepidoptera: Noctuidae) afeta diversas culturas de grande interesse econômico, por exemplo, pode causar severas perdas em milho, arroz e sorgo. Neste estudo, foi realizada uma seleção e caracterização de isolados de Bacillus thuringiensis (BERLINER, 1911) com elevada atividade inseticida contra S. frugiperda. Cinquenta e dois isolados formadores de cristal B. thuringiensis que foram identificados a partir de 3384 colônias foram examinados e testados por PCR para a presença dos genes cry (cry1, cry1Aa, cry1Ab, cry1Ac, cry1D, cry2 e cry2Ab). Quatro isolados que apresentaram alta toxicidade contra S. frugiperda foram mostrados para abrigar os genes cry2. Os cristais foram analisados por microscopia eletrônica e mostraram formas bipiramidais e cúbicas. Os valores da concentração letal (CL50) destes quatro isolados foram de 44,5 ng / cm2 (SUFT01), 74,0 ng / cm2 (SUFT02), 89,0 ng / cm2 (SUFT03) e 108 ng / cm2 (suft 04) para larvas recém-eclodidas de S. frugiperda. Uma análise ultra-estrutural das células do intestino médio de S. frugiperda incubadas com complexo esporo-cristal do isolado SUFT01 mostrou rupturas na integridade celular e microvilosidades das células cilíndricas do intestino médio. Neste estudo, o alto nível de atividade inseticida de isolados os torna excelentes candidatos para o controlo de S. frugiperda, e pode proporcionar alternativas no controle destas populações de pragas, bem como a formação de novos bioinsecticidas.

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