ABSTRACT
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)
Subject(s)
Animals , Information Systems , Lepidoptera/parasitology , VenezuelaABSTRACT
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 Ìs 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)
Subject(s)
Humans , Male , Female , Pest Control , Poisons , Environmental HealthABSTRACT
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.
Subject(s)
Humans , Animals , Male , Female , Adult , Young Adult , Simuliidae , Health Knowledge, Attitudes, Practice , Mosquito Control , Health Education , Brazil , Surveys and Questionnaires , Middle AgedABSTRACT
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).
Subject(s)
Humans , Animals , Disease Vectors , Entomology/education , Insect Control , Insect Vectors , Teaching/statistics & numerical data , Africa , Asia , Cattle , Central America , Disease Transmission, Infectious , Education, Distance/statistics & numerical data , Entomology/statistics & numerical data , Jupiter , Language , North America , South AmericaABSTRACT
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.
Subject(s)
Bacillus thuringiensis , Spodoptera , Insecticides , LepidopteraABSTRACT
Introduction: Understanding Aedes (Stegomyia) aegypti (L) behavior will provide insight into the design of entomological surveillance devices. Objective: Design and build a trap for surveillance Aedes aegypti. Methodology: We examined egg-laying preference and the ability to capture adult Ae. aegypti using containers that differed in shape, color and internal retention systems. The characteristics most effective in capturing adult mosquitoes were used to develop a prototype efficient in trapping mosquitoes. The shape of the prototype was determined by examining oviposition preference of containers having circular, square and triangular bases. Color discrimination was assessed by covering the bodies of the containers in green (523 nm), red (621 nm), white and gray (the chromatic scale from black to white). The propensity of Ae. aegypti to enter the containers was assessed by incorporating an entrance to the container in the shape of an inverted truncated oblique pyramid with base, middle and apex dimensions of 6.5-4 cm, 5-2.5 cm and 4.5-1.5 cm, respectively. All variables as the number of egg and adults captured in treatments were subjected to variance analysis; only data with P < 0.05 were considered significant. Results: Our results indicate that neither shape nor entrance dimension attract ovipositing Ae. aegypti females [K-W: H (3, N = 64) = 0.3222769 p = 0.9558 and K-W: H (3, N= 16) = 4.284865 p = 0.2323, respectively]. However, we found that the color red had a high positive response [K-W: H (4, N = 80) = 20.81260 p = 0.0003]. Conclusions: The final design of the trap resembled a truncated pyramid with a red square base, a black oblique entrance of 5 x 2.5 cm and an internal retention system. The final prototype had a capture rate of 90.5 ± 5% under laboratory conditions.
Introducción: Aspectos etológicos de Aedes (Stegomyia) aegypti (L) proporcionan el conocimiento para diseñar dispositivos para la vigilancia entomológica. Objetivo: Diseñar y construir una trampa para el monitoreo de Aedes aegypti. Metodología: Experimentos de ovipostura y captura de alados de Ae. aegypti fueron realizados con contenedores diseñados de acuerdo a forma, color y sistemas internos de retención. Las contenedores con mayor eficiencia de ovipostura y captura de adultos fueron usados para diseñar el prototipo de la trampa. La forma del dispositivo se determinó por medio de la preferencia de ovoposición con prototipos de base circular, cuadrada y triangular. La discriminación por el color, se evaluó cubriendo los contenedores de color verde (523 nm), rojo (621 nm), blanco y gris (que pertenecen a la escala cromática que va del negro al blanco), todos con una abertura de entrada de color negro. La capacidad de ingreso de Ae. aegypti a los contenedores fue evaluada incorporando una entrada al contenedor en forma de pirámide oblicua truncada invertida con dimensiones en la base, área media y ápice de 6,5-4 cm, 5-2,5 cm y 4,5-1,5 cm respectivamente. Todos los experimentos fueron sometidos a análisis de variancia con el programa "Statistica v11", únicamente datos con p < 0.05 se consideraron significativos. Resultados: Los resultados indicaron que la forma no influencia la atracción de ovoposición de las hembras de Ae. aegypti [K-W: H (3, N = 64) = 0.3222769 p = 0.9558] y el color rojo presenta alta selección (K-W: H (4, N = 80) = 20.81260 p = 0.0003). Las dimensiones de la entrada no tienen significancia en la captura de los mosquitos[K-W: H (3, N= 16) = 4.284865 p = 0.2323]. Conclusión: El diseño final de la trampa tuvo forma de pirámide truncada de base cuadrada de color rojo, con entrada oblicua negra de dimensiones de entrada 5 x 2,5 cm más un sistema interno de retención. El prototipo final presentó 90.5 ± 5 % de captura en los experimentos de laboratorio.
Subject(s)
Animals , Oviposition , Insect Control , Aedes , Behavior , Disease VectorsABSTRACT
OBJECTIVE@#To evaluate toxic activities of essential oils obtained from Rosmarinus officinalis and Lavandula stoechas against the fourth larval instars of Orgyia trigotephras.@*METHODS@#A total of 1 200 larvae were divided into three groups I II III. Group I was to investigate the effect of extracted essential oils from these aromatic plants as gastric disturbance. Bacillus thuringiensis and ethanol were used as control group. Group II was used as contact action and Group III was used as fumigant action. Decis and ethanol were used as control group. During the three experiments, the effect of essential oils on larvae was assessed.@*RESULTS@#The chemical composition of essential oils from two medicinal plants was determined and, their insecticidal effects on the fourth larval state of Orgyia trigotephras were assessed. The two simples presented an insecticidal activity, nevertheless Rosmarinus officinalis essential oil was less efficient compared to Lavandula stoechas one are discussed.@*CONCLUSIONS@#The relationship between the chemical composition and the biological activities is confirmed by the present findings. Therefore the potential uses of these essential oils as bioinsecticides can be considered as an alternative to the use of synthetic products.
ABSTRACT
Objective:To evaluate toxic activities of essential oils obtained fromRosmarinus officinalis andLavandula stoechas against the fourth larval instars of Orgyia trigotephras.Methods:A total of1200 larvae were divided into three groups 栺,栻,栿.Group 栺 was to investigate the effect of extracted essential oils from these aromatic plants as gastric disturbance.Bacillus thuringiensis and ethanol were used as control group.Group 栻 was used as contact action and Group 栿 was used as fumigant action.Decis and ethanol were used as control group.During the three experiments, the effect of essential oils on larvae was assessed.Results:The chemical composition of essential oils from two medicinal plants was determined and, their insecticidal effects on the fourth larval state ofOrgyia trigotephras were assessed.The two simples presented an insecticidal activity, neverthelessRosmarinus officinalis essential oil was less efficient compared toLavandula stoechasone are discussed.Conclusions:The relationship between the chemical composition and the biological activities is confirmed by the present findings.Therefore the potential uses of these essential oils as bioinsecticides can be considered as an alternative to the use of synthetic products.
ABSTRACT
Objective: To evaluate toxic activities of essential oils obtained from Rosmarinus officinalis and Lavandula stoechas against the fourth larval instars of Orgyia trigotephras. Methods: A total of 1 200 larvae were divided into three groups I II III. Group I was to investigate the effect of extracted essential oils from these aromatic plants as gastric disturbance. Bacillus thuringiensis and ethanol were used as control group. Group II was used as contact action and Group III was used as fumigant action. Decis and ethanol were used as control group. During the three experiments, the effect of essential oils on larvae was assessed. Results: The chemical composition of essential oils from two medicinal plants was determined and, their insecticidal effects on the fourth larval state of Orgyia trigotephras were assessed. The two simples presented an insecticidal activity, nevertheless Rosmarinus officinalis essential oil was less efficient compared to Lavandula stoechas one are discussed. Conclusions: The relationship between the chemical composition and the biological activities is confirmed by the present findings. Therefore the potential uses of these essential oils as bioinsecticides can be considered as an alternative to the use of synthetic products.
ABSTRACT
Introducción. En Colombia, las poblaciones periurbanas de Lutzomyia longipalpis,vector del agente causal de la leishmaniasis visceral en el valle alto y medio del río Magdalena, pueden estar expuestas a aplicaciones de insecticidas con diferentes propósitos, por lo que es importante iniciar una vigilancia de la sensibilidad de esta especie a los insecticidas. Objetivo. Determinar en una cepa experimental de L. longipalpis los indicadores de sensibilidad (concentraciones y tiempos diagnósticos) para tres insecticidas de uso común en salud pública: el malatión, la deltametrina y la lambdacialotrina. Materiales y métodos. Se utilizó el método propuesto por los Centers for Disease Control and Prevention. Grupos de 10 a 15 hembras se expusieron a diferentes concentraciones de los insecticidas, utilizando botellas de vidrio de 250 ml como cámaras de prueba. La mortalidad se registró cada cinco minutos durante una hora. Se calcularon las concentraciones y los tiempos diagnósticos para cada insecticida. Resultados. En la cepa evaluada de L. longipalpis, las concentraciones y los tiempos diagnósticos fueron de 75 µg/ml y 25 minutos para el malatión, de 10 µg/ml y 35 minutos para la deltametrina y de 15 µg/ml y 30 minutos para la lambdacialotrina. Conclusión. Se estableció la línea base de la mortalidad frente a tres insecticidas en una cepa sensible del vector L. longipalpis. Estos indicadores permitirán establecer comparaciones con poblaciones del vector expuestas regular o esporádicamente a medidas de control químico y detectar, así, cambios en la sensibilidad de esta especie a los insecticidas.
Introduction: In Colombia, periurban populations of Lutzomyia longipalpis, vector of the causative agent of visceral leishmaniasis in the upper and middle valley of the Magdalena River, may be exposed to insecticide applications with different purposes. Thus, it is important to begin a susceptibility surveillance of this species to insecticides. Objective: To determine indicators of susceptibility to three insecticides habitually used in public health, such as malathion, deltamethrin and lambda-cyhalothrin in an experimental strain of L. longipalpis. Materials and methods: We used the method proposed by the Centers for Disease Control and Prevention. Groups of 10 to 15 unfed females were exposed to different concentrations of the insecticides using 250 ml glass bottles as test chambers. Mortality was registered every five minutes for an hour. Diagnostic concentrations and lethal times for each insecticide were calculated. Results: In the evaluated L. longipalpis strain, the diagnostic concentrations and times were 75 µg/ml and 25 minutes for malathion, 10 µg/ml and 35 minutes for deltamethrin, and 15 µg/ml during 30 minutes for lambda-cyhalothrin. Conclusions: Baseline data over mortality response to three insecticides were established in a susceptibility strain of L. longipalpis vector. These indicators will allow establishing comparisons with populations of L. longipalpis exposed regularly or sporadically to chemical control measures to detect changes in their resistance to these insecticides.
Subject(s)
Insecticide Resistance , Leishmaniasis , Psychodidae , Insect ControlABSTRACT
OBJECTIVE To evaluate the resistance of Aedes aegypti to temephos Fersol 1G (temephos 1% w/w) associated with the adaptive disadvantage of insect populations in the absence of selection pressure. METHODS A diagnostic dose of 0.28 mg a.i./L and doses between 0.28 mg a.i./L and 1.40 mg a.i./L were used. Vector populations collected between 2007 and 2008 in the city of Campina Grande, state of Paraíba, were evaluated. To evaluate competition in the absence of selection pressure, insect populations with initial frequencies of 20.0%, 40.0%, 60.0%, and 80.0% resistant individuals were produced and subjected to the diagnostic dose for two months. Evaluation of the development of aquatic and adult stages allowed comparison of the life cycles in susceptible and resistant populations and construction of fertility life tables. RESULTS No mortality was observed in Ae. aegypti populations subjected to the diagnostic dose of 0.28 mg a.i./L. The decreased mortality observed in populations containing 20.0%, 40.0%, 60.0%, and 80.0% resistant insects indicates that temephos resistance is unstable in the absence of selection pressure. A comparison of the life cycles indicated differences in the duration and viability of the larval phase, but no differences were observed in embryo development, sex ratio, adult longevity, and number of eggs per female. CONCLUSIONS The fertility life table results indicated that some populations had reproductive disadvantages compared with the susceptible population in the absence of selection pressure, indicating the presence of a fitness cost in populations resistant to temephos. .
OBJETIVO Avaliar a resistência de Aedes aegypti ao temefós Fersol 1G (temefós 1% p/p) quanto à desvantagem adaptativa ao inseto, na ausência de pressão de seleção. MÉTODOS Foi aplicada a dose diagnóstica de 0,28 mg i.a/L e concentrações entre 0,28 mg i.a/L e 1,4 mg i.a/L. Foram avaliadas amostras do vetor coletadas no município de Campina Grande entre 2007 e 2008, no estado da Paraíba. Para avaliar a competição na ausência de pressão de seleção, foram constituídos grupos de insetos com frequências iniciais de 20,0%, 40,0%, 60,0% e 80,0% de insetos resistentes, submetendo-os a dose diagnóstica por dois meses. Os ciclos de vida das populações suscetível e resistentes foram comparados avaliando-se as fases de desenvolvimento aquática e adulta, construindo-se tabelas de vida de fertilidade. RESULTADOS Não foram verificadas mortalidades nas populações de Ae. aegypti quando submetidas à dose diagnóstica de 0,28 mg i.a./L. A diminuição da mortalidade nas populações com 20,0%, 40,0%, 60,0% e 80,0% de indivíduos resistentes indica que a resistência ao temefós é instável na ausência de pressão de seleção. A comparação do ciclo de vida mostrou diferenças na duração da fase e viabilidade larval, mas não quanto ao desenvolvimento embrionário, razão sexual, longevidade dos adultos e número de ovos/fêmea. CONCLUSÕES Pelos parâmetros da tabela de vida de fertilidade constatou-se que algumas populações apresentaram desvantagens reprodutivas em relação à população suscetível na ausência de pressão de seleção, havendo custo adaptativo resultante da resistência ao temefós. .
Subject(s)
Animals , Female , Male , Aedes , Insecticide Resistance , Temefos , Aedes/growth & development , Brazil , Dengue/prevention & control , Insect Vectors/growth & development , Mosquito Control/methodsABSTRACT
OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs. .
OBJETIVO Avaliar a eficácia de composto de óleos essenciais de Azadirachta indica, Melaleuca alternifolia, Carapa guianensis e extrato fermentado de Carica papaya sobre larvas de Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). MÉTODOS O ensaio larvicida foi realizado em triplicata com 300 larvas para cada grupo experimental utilizando larvas de terceiro estádio, as quais foram expostas por 24h, em 2013. Os grupos foram: controles positivos com larvicida industrial (BTI) nas concentrações de 0,37 ppm (CP1) e 0,06 ppm (CP2); tratado com composto de óleos essenciais e extrato fermentado na concentração de 50,0% (G1); tratado composto e óleos essenciais e extrato fermentado na concentração de 25,0% (G2); tratado com composto de óleos essenciais e um extrato fermentado na concentração de 12,5% (G3); controle negativo com água (CN1) e controle dimetil sulfóxido (CN2). As larvas foram monitoradas a cada 60 min através de visualização direta. RESULTADOS Larvas dos grupos CN1 e CN2 não tiveram mortalidade durante o período de 24h de exposição, mas os grupos CP1 e CP2 apresentaram taxa de mortalidade de 100% em relação a CN1 e CN2. Os tratamentos G1, G2 e G3 exerceram atividade larvicida de 65,0%, 50,0% e 78,0%, respectivamente, quando comparados a CN1 e CN2. CONCLUSÕES A associação entre os três óleos essenciais de Azadirachta indica, Melaleuca alternifolia, Carapa guianensis e extrato fermentado de Carica papaya foi eficiente em todas as concentrações testadas, podendo ser utilizado no controle de larvas de terceiro estádio de A. aegypti linhagem Liverpool. .
Subject(s)
Animals , Aedes/drug effects , Plant Oils/pharmacology , Azadirachta/chemistry , Carica/chemistry , Larva/drug effects , Melaleuca/chemistry , Meliaceae/chemistry , Plant Oils/isolation & purification , Time FactorsABSTRACT
BACKGROUND: Essential oils extracted from aromatic and medicinal plants have many biological properties and are therefore an alternative to the use of synthetic products. The chemical composition of essential oils from two medicinal plants (Eucalyptus globulus and E. lehmannii) was determined and, their insecticidal effects on the third and fourth larval stages of Orgyia trigotephras were assessed. RESULTS: Larvae were collected from Jebel Abderrahmane (North-East of Tunisia), conserved in groups of 50/box (21 × 10 × 10 cm) at a temperature of 25°C. Larvae were tested for larvicidal activities of essential oils. Each oil was diluted in ethanol (96%) to prepare 3 test solutions (S1 = 0.05%, S2 = 0.10% and S3 = 0.50%). Essential oils were used for contact, ingestion and Olfactory actions and compared to reference products (Bacillus thuringiensis and Decis). Olfactory action of essential oils shows that larvae mortality is higher than contact action, lower than ingestion action. MTM and FTM of S3 of E. lehmannii were respectively 1 h 32 min and 1 h 39 min are higher than those of E. globulus (MTM = 51 min and FTM = 1 h 22 min 34 sec). Contact action of E. lehmannii oil shows low insecticidal activity compared to E. globulus. MTM are respectively (1 min 52 sec and 1 min 7 sec), FTM are (2 min 38 sec, 1 min 39 sec), are the shortest recorded for S3, on the third stage of larvae. The fourth stage of larvae, MTM are (2 min 20 sec and 2 min 9 sec), FTM are (3 min 25 sec, 3 min 19 sec). Ingestion action of essential oils is longer than the contact action, since the time of death exceeds 60 minutes for all species. CONCLUSION: Results shows that essential oils have a toxic action on nerves leading to a disruption of vital system of insects. High toxic properties make these plant-derived compounds suitable for incorporation in integrated pest management programs.
Subject(s)
Animals , Oils, Volatile/chemistry , Eucalyptus/chemistry , Insecticides , Lepidoptera , Tunisia , Chromatography, Gas , Plant Leaves/metabolism , Plant Leaves/chemistry , Cyclohexanols/analysis , Monoterpenes/analysis , Eucalyptus/classification , Biological Control Agents , Herbivory , Eucalyptol , Bicyclic Monoterpenes , Larva/drug effects , Life Cycle Stages/drug effectsABSTRACT
This work aimed to evaluate the toxicity of some insecticides compounds on Aedes aegypti and Artemia salina larvae. Bioassays were carried out to evaluate the toxic effect after of 24 and 72 h using the compounds or associations. The LC10, LC50 and LC90 values were obtained and utilized for toxicity comparations. For Ae. aegypti, LC50 were 32.65 mg L-1 in 24 h for Na2[EDTA-Cu(II)] and total mortality in 72 h for SAP-Na2[EDTA-Cu(II)].
ABSTRACT
Bioensaios concentração-resposta foram realizados com o objetivo de estudar o efeito larvicida e detectar possível resistência à ivermectina em dez populações de M. domestica provenientes de granjas de galinhas poedeiras. Para tal finalidade, o meio de cultura para larvas foi tratado com diferentes concentrações de ivermectina (0,015; 0,03; 0,06; 0,125; 0,25 e 0,5 ppm). Atividade larvicida da ivermectina e anomalias nas pupas foram detectadas. A população mais resistente à ivermectina foi Monte Mor, SP (CL= 0,262 ppm e FR= 13,1). As populações de Campinas, SP (CL= 0,141 ppm 50 50 e FR = 7,1), Promissão, SP (CL= 0,110 ppm e FR = 5,5), Santa Cruz da Conceição, SP (CL= 0,102 50 50 ppm e FR = 5,1), Holambra, SP (CL= 0,071 ppm e FR = 3,6) e Hortolândia, SP (CL= 0,068 ppm e 50 50 FR = 3,4) foram mais resistentes que as de Sumaré, SP (CL= 0,052 ppm e FR = 2,6), Sarapuí, SP (CL 50 50 = 0,050 ppm e FR = 2,5) e Itanhandu, MG (CL50 = 0,047 ppm e FR = 2,4). A população mais susceptível à ivermectina foi Grande Porto Alegre, RS (CL50 = 0,020 ppm e FR = 1,0). Os resultados indicam que a ivermectina pode ser eficaz contra larvas deM. domestica. Entretanto, resistência foi suspeitada em algumas das populações, sendo importante a realização de novos estudos nesses locais.
Larvicidal effect and resistance to ivermectin in 10 populations of Musca domestica from poultry farms was evaluated by concentration-response bioassays. For this purpose, the larval growth medium was treated with different concentrations of ivermectin (0.015, 0.03, 0.06, 0.125, 0.25 and 0.5 ppm). As a result, larvicidal activity of ivermectin was observed and some anomalies were detected in pupae. The population from Monte Mor, SP, was the most resistant to ivermectin (LC50 = 0.262 ppm and RF = 13.1). Fly populations from Campinas, SP (LC50 = 0.141 ppm and RF = 7.1), Promissão, SP (LC50 = 0.110 ppm and RF = 5.5), Santa Cruz da Conceição, SP (LC50 = 0.102 ppm and RF = 5.1), Holambra, SP (LC50 = 0.071 ppm and RF = 3.6) and Hortolândia, SP (LC50 = 0.068 ppm and RF = 3.4) were more resistant than the ones from Sumaré, SP (LC50 = 0.052 ppm and RF = 2.6), Sarapuí, SP (LC50 = 0.050 ppm and RF = 2.5), and Itanhandu, MG (LC50 = 0.047 ppm and RF = 2.4). The population most susceptible to ivermectin was that from Grande Porto Alegre, RS (LC50 = 0.020 ppm and RF = 1.0). The results indicate that ivermectin can be effective against larvae ofM. domestica. However, since resistance was suspected in some of the populations studied, it is important to carry out new studies in these places.
Subject(s)
Animals , Poultry/parasitology , Ivermectin/administration & dosage , Ivermectin/analysis , Chickens , Houseflies/immunology , Disk Diffusion Antimicrobial TestsABSTRACT
This work aimed to evaluate the toxicity of some insecticides compounds on Aedes aegypti and Artemia salina larvae. Bioassays were carried out to evaluate the toxic effect after of 24 and 72 h using the compounds or associations. The LC10, LC50 and LC90 values were obtained and utilized for toxicity comparations. For Ae. aegypti, LC50 were 32.65 mg L-1 in 24 h for Na2[EDTA-Cu(II)] and total mortality in 72 h for SAP-Na2[EDTA-Cu(II)].
Aedes aegypti é inseto de grande interesse na Saúde Pública por transmitir o vírus da Dengue, Febre Amarela e Febre Hemorrágica da Dengue. No controle do mosquito utilizam-se inseticidas organoclorados, organofosforados, carbamatos e piretróides que guiam à seleção de insetos resistentes. A combinação de íons metálicos de transição, EDTA, STI e SAP são propostos como estratégia efetiva e persistente para o controle de larvas de Ae. aegypti através de danos ao sistema digestório por radicais livres. A toxicidade dos compostos foi avaliada para Ae. aegypti e A. salina (organismo não alvo). Os bioensaios foram conduzidos para avaliar o efeito tóxico dos compostos e associações após 24 e 72 horas. As CL10, CL50 e CL90 foram obtidas para comparações de toxicidade. Para Ae. aegypti a CL50 foi 32,65 mg L-1 em 24 horas para Na2[EDTA-Cu(II)] e mortalidade total a 62,5 mg.L-1para quelato em polímero acrílico de liberação lenta SAP-Na2[EDTA-Cu(II)] em até 72 horas.
ABSTRACT
This study was carried out to evaluate the residual effect of three larvicides under laboratory conditions for 100 days in Aedes aegypti. The larval mortality rate was measured without water renewal or with daily water renewal (80 percent). With temephos, there was 100 percent mortality in both groups until the 70th day. In the Bacillus thuringiensis israelensis (Bti)-WDG test, there was no difference during the first 20 days. With Bti-G, without water renewal, mortality was sustained above 90 percent for up to 35 days. The second experiment (with water renewal) reduced the mortality to below 90 percent after the first 20 days. When renewed water was provided, the residual effect was significantly lower for all larvicides.
Subject(s)
Animals , Aedes , Insect Vectors , Insecticides , Pesticide Residues/pharmacology , Temefos , Water , Larva , Mosquito Control , Time FactorsABSTRACT
A transmissão da doença de Chagas ocorre, principalmente, por meio de fezes de hemípteros hematófagos (Triatominae), os quais ingerem o Trypanosoma cruzi ao se alimentarem do sangue de pessoas ou outros mamíferos infectados. Para o controle dos triatomíneos, os piretróides são os principais inseticidas utilizados. Entretanto, algumas populações de insetos demonstraram resistência a determinados piretróides, indicando a necessidade do desenvolvimento de novos inseticidas eficazes no controle desses vetores. Assim, foi avaliada a atividade inseticida de 83 extratos vegetais, pertencentes a 35 espécies diferentes, em ninfas do primeiro estádio de Dipetalogaster maxima (Uhler, 1894) (Hemiptera: Reduviidae), triatomíneo encontrado no México. Para o teste tópico, foram aplicados 50 ìg de cada extrato nos tergitos abdominais de dez ninfas, em duplicata. Como controles, foram utilizados insetos tratados com etanol, acetona ou sem nenhum tipo de tratamento. Os triatomíneos foram observados durante 28 dias. Nenhum extrato apresentou atividade inseticida significativa, entretanto, o extrato hexânico do fruto e o etanólico da casca do caule de Simarouba versicolor (Simaroubaceae) inibiram a taxa de ecdise em D. maxima (40 por cento e 25 por cento, respectivamente). Sugere-se que estes extratos sejam quimicamente investigados e monitorados por ensaios biológicos a fim de determinar os componentes, para que estes possam ser utilizados como modelos moleculares ou como compostos biorracionais nos programas de controle de insetos.
Chagas disease, also known as American Trypanosomiasis, is chiefly transmitted by faeces of haematophagous bugs (Triatominae) that ingested Trypanosoma cruzi from blood of infected people or other mammals. Pyrethroids have been the main insecticides used against these insects. However, some populations of insects have shown significant levels of resistance to several pyrethroids, indicating the need of new insecticides for the control of triatomines. Thus, the insecticidal activity of 83 Cerrado plant extracts belonging to 35 species were assayed on first instar nymphs of Dipetalogaster maxima (Uhler, 1894) (Hemiptera, Reduviidae), species found in Mexico. For the extract application on triatomines, 50 μg of the extract were topically applied in duplicate on dorsal tergites of ten insects. Insects topically treated with acetone, ethanol, as well as insects with no treatment were used as controls. Triatomines were observed over a 28-day period. The extracts showed no insect mortality, however, fruit hexane and stem bark ethanolic extracts of Simarouba versicolor (Simaroubaceae) inhibited the rate of ecdysis in D. maxima (40 percent and 25 percent, respectively). These preliminary data suggest that this extracts should be chemically investigated and monitored through biological assays in order to determine the components, so that it may be used as a molecular model or as biorational compounds for use in insect control programmes.
ABSTRACT
Avaliaram-se os efeitos dos extratos aquosos a 10 por cento de folhas e ramos de arruda (Ruta graveolens L.), folhas e ramos de melão-de-são-caetano (Momordica charantia L.), folhas do alecrim-pimenta (Lippia sidoides Cham.) e fruto verde de mamona (Ricinus communis L.), sobre a biologia da lagarta-do-cartucho do milho (Spodoptera frugiperda), mantida em dieta artificial. Os parâmetros avaliados foram duração e viabilidade das fases larval e pupal, peso de pupa, fecundidade, fertilidade e longevidade de adultos. Larvas de S. frugiperda recém-eclodidas foram colocadas em tubos de ensaio com dieta artificial, contendo os extratos de cada material testado. O extrato aquoso do fruto verde de R. communis apresentou bioatividade, nos parâmetros duração larval e pupal e peso de pupa. O extrato aquoso de R. graveolens reduziu o peso de pupa. A dieta contendo extrato de folhas e ramos de M. charantia reduziu a viabilidade larval e o peso de pupa. O extrato aquoso de folhas de L. sidoides não afetou as fases larval e pupal, reduziu a postura e a viabilidade de ovos e aumentou a longevidade de adultos de S. frugiperda. A viabilidade de pupa não foi afetada pelos extratos testados.
The effects of aqueous extracts, at 10 percent concentration of leaves and branches of Ruta graveolens L., leaves and branches of Momordica charantia L., leaves of Lippia sidoides Cham. and green fruits of Ricinus communis L. were evaluated on the biology of fall armyworm (Spodoptera frugiperda) maintained under artificial diet. The evaluated parameters were: duration and viability of the larval and pupal phases, pupa weight, fecundity, fertility and longevity of adults. Just-hatched larvae of S. frugiperda was placed in test tube with artificial diet containing extracts of each tested material. The aqueous extract of the green fruits of R. communis presented bioactivity upon duration and weight of larval and pupal phases. The aqueous extract of R. graveolens reduced weight of pupa. The diet containing extract of M. charantia reduced larval viability and weight of pupa. The aqueous extract of L. sidoides did not affect larval and pupal phases, but reduced the posture and the viability of eggs and increased longevity of adults of S. frugiperda. The viability of pupa was not affected by the extracts.
ABSTRACT
Tricorynus herbarius (Gorham) é uma potencial praga de livros, especialmente em obras raras devido à composição do papel destas. Há carência de trabalhos referentes à sua biologia, principalmente por se tratar de um inseto que apresenta vários hábitos alimentares, sendo esse estudo uma etapa fundamental para o controle do inseto. Assim, a biologia de T. herbarius foi estudada em insetos mantidos em duas dietas diferentes: papel mata-borrão e farelo de trigo mais levedura de cerveja. Quatro ínstares foram obtidos em ambas dietas. A duração do período larval e a longevidade dos adultos foram mais curtas e a duração do período pupal foi maior quando os insetos foram mantidos em papel mata-borrão. Em ambas dietas a mortalidade foi alta, sempre acima de 50 por cento. A fecundidade observada para as fêmeas foi de 3,3 ± 3,93 ovos/fêmea em papel mata-borrão e 12,1 ± 12,61 em farelo de trigo. A razão sexual foi 0,5 para ambas dietas. A dieta de farelo de trigo mais levedura de cerveja mostrou-se a mais adequada para criação de T. herbarius.
Tricorynus herbarius (Gorham) is a potential bibliophagous insect, especially for rare books due to paper constituents of them. There are few studies with regards to the biology of this insect, perhaps because T. herbarius feeds on different resources, being this study an important feature to control the pest. The biological parameters of T. herbarius were studied in two different diets: blotting paper and wheat meal plus yeast extract. Four instars were obtained on both diets. The length of the larval period and adult longevity were shorter while the pupal period was longer when the insects fed on blotting paper. In both diets mortality was high, over 50 percent. Female fecundity was 3.3 ± 3.93 eggs per female for blotting paper and 12.1 ± 12.61 for wheat meal plus yeast extract. The sex rate was 0.5 for both diets. Wheat meal plus yeast extract is the best diet for rearing the book borer T. herbarius.