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Resíduos de pirimifós-metil em grãos de trigo, milho e milho pipoca, em alguns de seus produtos processados e ação residual desse inseticida sobre Sitophilus spp. (Coleoptera, Curculionidae).; Residues of pirimiphos-metil on wheat, corn and popcorn grains, in some of their processed products and residual action of the insecticide on Sitophilus spp. (Coleoptera, Curculionidae).

Sgarbiero, Eduardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/03/2002 PT
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Os objetivos do presente trabalho foram avaliar a ocorrência / persistência / degradação de resíduos do inseticida organofosforado pirimifós-metil em grãos de trigo, milho e milho pipoca e em alguns de seus produtos processados, bem como a ação residual desse inseticida sobre Sitophilus spp. (Coleoptera, Curculionidae). O tratamento dos grãos foi realizado de modo a se obter a concentração teórica de 12 mg.kg-1 (ppm) de pirimifós-metil, tendo sido aplicados o equivalente a 5 litros de solução por tonelada de grãos. As amostras para estudos de resíduos foram tomadas aos zero, 15, 30, 60, 120 e 240 dias após o tratamento. O método analítico consta da extração dos resíduos com acetona, limpeza com partição acetonitrila/hexano seguida de coluna cromatográfica de sílica eluída com mistura de hexano+acetona (9/1, v/v). A determinação quantitativa foi feita por técnica de cromatografia em fase gasosa, usando-se cromatógrafo equipado com detector fotométrico de chama (GLC/FPD). Foram analisadas 264 amostras no total, sendo 72 de grãos cereais e 192 de seus produtos processados. Para os estudos de ação residual do inseticida sobre adultos de Sitophilus spp. os insetos foram submetidos a testes em exposição aos grãos tratados após 15 dias decorridos do tratamento...

Efeito da aplicação de inseticida na epidemiologia da clorose letal das Cucurbitáceas (Zucchini lethal chlorosis virus - ZLCV) em abobrinha de moita (Cucurbita pepo L.); Effect of insecticide spray in lethal chlorosis (Zucchini lethal chlorosis virus - ZLCV) epidemiology in Cucurbita pepo L.

Costa, Caroline Rabelo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 14/03/2013 PT
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O manejo de fitoviroses muitas vezes é realizado com o uso de inseticidas para o controle do vetor. Para o patossistema Frankliniella zucchini / Cucurbita pepo / Zucchini lethal chorosis virus (ZLCV) não existe informação na literatura sobre a eficiência do controle da doença por meio do controle químico do vetor. Para tanto foi proposto este trabalho, que tem ainda por objetivo uma melhor compreensão da epidemiologia da doença em seus aspectos temporal e espacial. Os experimentos foram conduzidos na estação experimental de Fitopatologia da Escola Superior de Agricultura "Luiz de Queiroz" no período de março de 2010 a dezembro de 2011. Campos de abobrinha de moita foram divididos em parcelas com e sem aplicação do inseticida neonicotinóide Imidacloprid. As avaliações da doença foram feitas com base nos sintomas foliares característicos da doença, em intervalos de três a quatro dias, e confirmados por meio de teste ELISA. A Clorose Letal apresentou incidências de 11,58% e 52,55% em parcelas com inseticida e de 21,36% e 69,89% em parcelas sem inseticida, para os anos de 2010 e 2011, respectivamente. Em todos os casos, o modelo monomolecular apresentou melhor ajuste aos dados temporais e as plantas sintomáticas distribuíram-se aleatoriamente nas parcelas. Esses resultados sugerem que a disseminação primária é o processo predominante na epidemiologia da doença. A disseminação primária...

Evaluation of Insecticide Resistance and Biochemical Mechanisms in a Population of Culex quinquefasciatus (Diptera: Culicidae) from São Paulo, Brazil

Bracco,José Eduardo; Barata,José Maria S; Marinotti,Osvaldo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1999 EN
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To establish an insecticidal resistance surveillance program, Culex quinquefasciatus mosquitoes from São Paulo, Brazil, were colonized (PIN95 strain) and analyzed for levels of resistance. The PIN95 strain showed low levels of resistance to organophosphates [malathion (3.3-fold), fenitrothion (11.2-fold)] and a carbamate [propoxur (3.0-fold)]. We also observed an increase of 7.4 and 9.9 in a and b esterase activities, respectively, when compared with the reference IAL strain. An alteration in the sensitivity of acetylcholinesterase to insecticide inhibition was also found in the PIN95 mosquitoes. The resistant allele (Ace.1R), however, was found at low frequencies (0.12) and does not play an important role in the described insecticide resistance. One year later, Cx. quinquefasciatus mosquitoes were collected (PIN96 strain) at the same site and compared to the PIN95 strain. The esterase activity patterns observed for the PIN96 strain were similar to those of the PIN95 mosquitoes. However the occurrence of the Ace.1R allele was statistically higher in the PIN96 strain. The results show that esterase-based insecticide resistance was established in the PIN95 Cx. quinquefasciatus population and that an acethylcholinesterase based resistant mechanism has been selected for. A continuous monitoring of this phenomenon is fundamental for rational mosquito control and insecticide application programs.

Vegetative growth and yield of tomato (Lycopersicum esculentum Mill.) in response to the systemic insecticide phorate

Guedes,Raul N. C.; Guedes,Nelsa M. P.; Picanço,Marcelo
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/1998 EN
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The effect of the systemic insecticide phorate on vegetative growth and yield of tomato (Lycopersicum esculentum Mill.) was studied in the greenhouse. Three dosages of phorate (1.5, 7.5, and 13.5 mg a.i./ 1.5 L pot) were applied along with a control (without insecticide application). The plants were harvested at 17, 32, 51, 69, and 90 days after tilling. Regression analysis did not show any significant effect of insecticide dosages in plant and root length. However, an overall negative effect of phorate was observed on leaf area, shoot and root dry weights, and fruit fresh weight. Based on multiple regression models, maximum leaf area was obtained with 6.7 mg a.i./pot and maximum shoot and root dry weights were obtained with no insecticide application and 0.1 mg a.i./pot, respectively. Higher fruit fresh weights were also obtained without phorate application. Dosages of phorate close to the lower range recommended for pest control in tomatoes (1 kg a.i./ha) favored the increase in leaf area in tomato plants, but this increase did not cause higher yields. Phorate was slight detrimental to shoot and root growth, what led to a smaller yield in the phorate treated plants.

Entomopathogenic nematodes and their interaction with chemical insecticide aiming at the control of banana weevil borer, Cosmopolites Sordidus Germar (Coleoptera: Curculionidae)

Bortoluzzi,L.; Alves,L.F.A.; Alves,V.S.; Holz,N.
Fonte: Instituto Biológico Publicador: Instituto Biológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
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The banana weevil borer (Cosmopolites sordidus) is the main pest of banana crops, causing significant losses in productivity, being recommended control by chemical insecticides which cause several environmental impacts. On the other hand, entomopathogenic nematodes can be an alternative to the pest control, mainly because of their habits. Thus, this study aimed at evaluating isolated entomopathogenic nematodes under laboratory conditions and also their interaction with a chemical insecticide (carbofuran), aiming at their use for the weevil borer control. Sixteen Sterinernematidae and Heterorhabditidae isolates were evaluated, applied over the banana tree pseudo stem (100 JIs/cm²) and they were compared to one another concerning mortality caused in adults individual of C. sordidus. The most infective isolates were subjected to in vivo multiplication at the host Galleria mellonella and interaction with the insecticide carbofuran, including in this case, viability and infectivity analysis of the entomopathogenic nematodes exposed to the product, as well as the effect of the insecticide on the symbiotic bacteria of the entomopathogenic nematodes. The experiments at this stage were conducted in completely randomized design and the data were subjected to ANOVA...

Insecticide susceptibility of horn flies, Haematobia irritans (Diptera: Muscidae), in the State of Mato Grosso do Sul, Brazil

Barros,Antonio Thadeu M.; Gomes,Alberto; Koller,Wilson W.
Fonte: Colégio Brasileiro de Parasitologia Veterinária Publicador: Colégio Brasileiro de Parasitologia Veterinária
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2007 EN
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Horn fly susceptibility to insecticides was evaluated in the state of Mato Grosso do Sul, Brazil, from October 2000 to September 2002. Insecticide bioassays (n=57) were conducted in 38 ranches from 14 municipalities throughout the state. Horn flies from wild populations were collected on cattle and exposed to filter papers impregnated with cypermethrin, permethrin, or diazinon and mortality was assessed after two hours. Resistance to cypermethrin was detected in all populations, with resistance ratios (RR) ranging from 27.6 to 91.3-fold. Permethrin bioassays provided apparently low levels of resistance (RR<5), however, resistant flies were found in 96.9% of the populations based on diagnostic concentrations. From both pyrethroid bioassays, resistance was detected in 97.4% of the populations. On the other hand, a high susceptibility to diazinon (RR < 1.1) was detected in all populations. Pyrethroid products, most cypermethrin (92.3%) and deltamethrin (66.7%), were used in all ranches controlling horn flies (97.5%). Insecticide treatments, usually incorrectly applied, were routinely delivered by manual backpack sprayers in most ranches (84.5%). This profile of insecticide use helps to explain the widespread resistance of horn flies to pyrethroids in the state as well as their high susceptibility to the organophosphate. Inadequate control practices contribute to aggravate the resistance problem and its consequences.

Life-Stage Variation in Insecticide Resistance of the Western Flower Thrips (Thysanoptera: Thripidae)

Contreras, J.; Espinosa, P. J.; uinto, V.; Abellán, J.; Grávalos, C.; Fernández, E.; Bielza, P.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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The life-stage variations in insecticide resistance of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), to selective insecticides (acrinathrin, formetanate, and methiocarb) were studied using resistant laboratory strains. In each strain, the second-instar larva was less susceptible to the insecticides tested than the adults. The lower the resistance level of the adults, the higher the difference between larva and adult susceptibility: 32-fold to methiocarb, 15.4-fold to formetanate, and 180-fold to acrinathrin in the reference strain. In laboratory-selected resistant strains, these differences were much lower: 5.8-fold to methiocarb, 4.8-fold to formetanate, and 2.0-fold to acrinathrin. In selected strains, higher resistance levels for each insecticide were found, both for larvae and adults, compared with the reference strain. These results show that after insecticide resistance selection in adults, the resistance is carried over to the larvae, but at lower levels.

Corn Semiochemicals and Their Effects on Insecticide Efficacy and Insecticide Repellency Toward Western Corn Rootworm Larvae (Coleoptera: Chrysomelidae)

Hibbard, B. E.; Bjostad, L. B.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Volatile corn seedling (pre-stage 0 germinated seed) semiochemicals are attractive to larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte and were evaluated with insecticides in laboratory soil bioassays to determine attraction and increased mortality of larvae. Insecticides from four different chemical classer were tested. These were carbofuran (carbamate), fonofos (organophosphate), tefluthrin (pyrethroid), and 2’-bromo-4’-nitro-perfluorocyclohexane carboxanilide (EL-499, experimental, Eli Lilly Company). For each of the four insecticides tested in bioassays in soil with insecticide present in a central core, significantly more larvae were killed after 24 h when corn seedling volatiles were present in the core than when they were not. The enhanced rate of mortality was the result of larval attraction. In bioassays without soil present, significantly more larvae contacted an insecticide source after 30 min when corn seedling volatiles were present than when they were absent. Insecticide repellency was evaluated in soil bioassays (24 h) and in Petri dish bioassays (30 min) in the presence and absence of volatile corn seedling semiochemicals. Only fonofos was repellent, but the attractiveness of corn seedling semiochemicals overcame that repellency.

Monitoring and Characterization of Insecticide Resistance Codling Moth (Lepidoptera: Tortricidae) in Four Western States

Varela, L. G.; Welter, S. C.; Jones, V. P.; Brunner, J. F.; Riedl, H.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Variation in response to insecticide in codling moth, Cydia pomonella (L.), was surveyed in California, Oregon, Utah, and Washington. Two techniques (topical application and direct incorporation of insecticide into the trap adhesive) were used to assay male moths caught in pheromone traps. Using the LC75 from a susceptible population as a standard dose, we monitored 20 apple and pear orchards for resistance to azinphosmethyl by the topical application technique. Orchards in California had the greatest interpopulation variability in resistance levels. In a single pear orchard in the Sacramento Delta, the level of resistance at the LC50 was ≈6.2 and 7.2 times greater than in a susceptible population when bioassays were done by topical application and adhesives were mixed with insecticide, respectively. Residual bioassays with neonate larvae collected from this site indicated 4.6-fold resistance. Orchards in Oregon showed little variability, and all populations appeared to be susceptible. Populations from Utah orchards showed little variability in the bioassay and were the most susceptible in the four states tested. Populations collected from Washington orchards had the highest tolerance levels. In laboratory tests...

Comparative Fitness of Three Strains of Colorado Potato Beetle (Coleoptera: Chrysomelidae) in the Field: Spatial and Temporal Variation in Insecticide Selection

Follett, Peter A.; Gould, Fred; Kennedy, George G.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Fitness components were measured for permethrin-resistant, susceptible, and hybrid strains of Colorado potato beetle, Leptinotarsa decemlineata (Say), on insecticide-treated and untreated potato, Solanum tuberosum L., under field conditions. The hybrid strain was created by crossing resistant females and susceptible males. In separate experiments, survivorship was determined for adults and larvae of various ages (1, 2, 4, and 6 d) that were exposed directly to a permethrin (Ambush 2EC) spray. Results indicated that there is significant selection against susceptible genotypes during all larval stages and the adult stage. One- and 2-d-old larvae, as well as adults, of the hybrid strain and the resistant strain had similar survival. Survival in 4- and 6-d-old larvae of the hybrid strain was intermediate between the susceptible and resistant strains. Weights of 4- and 6-d-old larvae of the resistant and hybrid strains that survived treatment with insecticide were significantly lower than weights of untreated larvae. In another set of experiments, viability of 1-d-old larvae and viability and fecundity of adults were estimated when beetles were placed on potato foliage at various intervals (2, 5, 8 and 13 d) after permethrin application. Selection against susceptible 1-d-old larvae was strongest when placement was 2 d after application and selection diminished on subsequent placement dates but remained significant for the duration of the experiment. Selection against susceptible larvae was more intense on old foliage than new foliage. Larvae of the hybrid and resistant strains had similar survival on treated foliage. When hybrid 1-d-old larvae were placed on foliage 2 and 5 d after application...

Cytochrome P450 MA Expression in Insecticide-Resistant German Cockroaches (Dictyoptera: Blattellidae)

Scharf, Michael E.; Lee, Chow-Yang; Neal, Jonathan J.; Bennett, Gary W.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Cytochrome P450 monooxygenases are detoxification enzymes commonly involved in insecticide resistance by insects. Recently, an overexpressed form of this enzyme, P450 MA, was purified from an insecticide-resistant strain of German cockroach, Blattella germanica (L.), and polyclonal antisera (anti-P450 MA) was produced. To test hypotheses that the overexpressed condition of P450 MA has evolved in >1 geographic location and that P450 MA might be involved in insecticide resistance to specific insecticides, investigations were conducted using 4 insecticide-resistant and 1 susceptible German cockroach strains. In western blots that used anti-P450 MA antiserum as a probe, substantial differences in expression of P450 MA were observed. Strains showing the highest P450 MA expression had both the highest tolerance to the organophosphate insecticide chlorpyrifos and cytochrome P450-mediated demethylation activity. Results support the hypothesis that cytochrome P450 MA is potentially overexpressed in insecticide-resistant populations on a global scale.

Greenbug Resistance Management on Sorghum with Insecticide Mixtures: a Biological and Economic Analysis

Archer, T. L.; Segarra, Eduardo; Bynum, E. D.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Several tactics were evaluated for insecticide resistant greenbug, Schizaphis graminum (Rondani), control on sorghum. During the first 2 yr of this research, control by chlorpyrifos, carbofuran, and malathion and mixtures of the latter 2 chemicals plus piperonyl butoxide with chlorpyrifos were compared on sorghum. Chlorpyrifos provided <60% control. The mixtures of chlorpyrifos + carbofuran or malathion provided good control of insecticide resistant greenbug. The mixture of chlorpyrifos + piperonyl butoxide provided mediocre control of resistant greenbugs. In 1996, an experiment was designed to evaluate the effects of greenbug population insecticide resistance ratio and preexposure of greenbugs to chlorpyrifos on control by mixtures of chlorpyrifos with carbofuran or malathion. About half of the plots were presprayed with chlorpyrifos (0.28 kg [AI]/ha) 4 d before applying individual insecticides or mixtures. Plots were infested with 2 ratios of resistant: susceptible greenbugs (1:3 and 3:1, respectively). Application of mixtures of chlorpyrifos + malathion provided best control followed by chlorpyrifos + carbofuran and chlorpyrifos. Prespraying greenbugs with chlorpyrifos did not affect their control with subsequent insecticide resistance management mixtures. The difference between the 2 ratios was significant with the lowest greenbug densities in plots dominated by susceptible individuals. There was a significant yield response to greenbug densities. The highest yields were obtained in plots sprayed with chlorpyrifos + malathion mixtures. When chlorpyrifos was applied to greenbug populations dominated by resistant aphids...

Effect of cypermethrin insecticide on the microbial community in cucumber phyllosphere

Zhang, B.; Zhang, H.; Jin, B.; Tang, L.; Yang, J.; Li, B.; Zhuang, G.; Bai, Z.
Fonte: I O S Press Publicador: I O S Press
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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Cucumber (Cucumis sativus) is one of the most widely used vegetable in the world, and different pesticides have been extensively used for controlling the insects and disease pathogens of this plant. However, little is known about how the pesticides affect the microbial community in cucumber phyllosphere. This study was the first attempt to assess the impact of pyrethroid insecticide cyperemethrin on the microbial communities of cucumber phyllosphere using biochemical and genetic approaches. Phospholipid fatty acid (PLFA) assay indicated that cyperemethrin insecticide treatment led to a significant increase in both total and bacterial biomass and a decrease in fungal biomass and the ratio of Gram-positive (GP) bacteria to Gram-negative (GN) bacteria within the cucumber phyllosphere. Principal-component analyses (PCA) suggested that the number of unsaturated and cyclopropane PLFAs (16:1 omega 9t, 18:1 omega 7, cy17:0, cy19:0) increased with the insecticide treatment, whereas the saturated PLFA i16:0, i17:0 decreased. The increase of GN bacteria implied that the cypermethrin insecticide might be a nutrient for the growth of these phyllosphere microbes. Terminal restriction fragment length polymorphism (T-RFLP) reinforced the PLFA results. A significant change of bacterial community structure was observed in the separate dendrogram cluster between control and treated samples with the cucumber phyllosphere following cypermethrin insecticide treatment. Moreover...

History of insecticide resistance of Triatominae vectors

Pessoa,Grasielle Caldas Dávila; Vinãs,Pedro Albajar; Rosa,Aline Cristine Luiz; Diotaiuti,Liléia
Fonte: Sociedade Brasileira de Medicina Tropical - SBMT Publicador: Sociedade Brasileira de Medicina Tropical - SBMT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
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AbstractIn the last 15 years, different types of Triatominae resistance to different insecticides have been reported; thus, resistance may be more widespread than known, requiring better characterization and delimitation, which was the aim of this review. This review was structured on a literature search of all articles from 1970 to 2015 in the PubMed database that contained the keywords Insecticide resistance and Triatominae . Out of 295 articles screened by title, 33 texts were selected for detailed analysis. Insecticide resistance of Triatomines is a complex phenomenon that has been primarily reported in Argentina and Bolivia, and is caused by different factors (associated or isolated). Insecticide resistance of Triatominae is a characteristic inherited in an autosomal and semi-dominant manner, and is polygenic, being present in both domestic and sylvatic populations. The toxicological profile observed in eggs cannot be transposed to different stages of evolution. Different toxicological profiles exist at macro- and microgeographical levels. The insecticide phenotype has both reproductive and developmental costs. Different physiological mechanisms are involved in resistance. Studies of Triatomine resistance to insecticides highlight three deficiencies in interpreting the obtained results: I) the vast diversity of methodologies...

Evolution of insecticide resistance in non-target black flies (Diptera: Simuliidae) from Argentina

Montagna,Cristina Mónica; Gauna,Lidia Ester; D'Angelo,Ana Pechen de; Anguiano,Olga Liliana
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
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Black flies, a non-target species of the insecticides used in fruit production, represent a severe medical and veterinary problem. Large increases in the level of resistance to the pyrethroids fenvalerate (more than 355-fold) and deltamethrin (162-fold) and a small increase in resistance to the organophosphate azinphos methyl (2-fold) were observed between 1996-2008 in black fly larvae under insecticide pressure. Eventually, no change or a slight variation in insecticide resistance was followed by a subsequent increase in resistance. The evolution of pesticide resistance in a field population is a complex and stepwise process that is influenced by several factors, the most significant of which is the insecticide selection pressure, such as the dose and frequency of application. The variation in insecticide susceptibility within a black fly population in the productive area may be related to changes in fruit-pest control. The frequency of individuals with esterase activities higher than the maximum value determined in the susceptible population increased consistently over the sampling period. However, the insecticide resistance was not attributed to glutathione S-transferase activity. In conclusion, esterase activity in black flies from the productive area is one mechanism underlying the high levels of resistance to pyrethroids...

Plant compounds insecticide activity against Coleoptera pests of stored products

Moreira,Márcio Dionizio; Picanço,Marcelo Coutinho; Barbosa,Luiz Cláudio de Almeida; Guedes,Raul Narciso Carvalho; Campos,Mateus Ribeiro de; Silva,Gerson Adriano; Martins,Júlio Cláudio
Fonte: Embrapa Informação Tecnológica; Pesquisa Agropecuária Brasileira Publicador: Embrapa Informação Tecnológica; Pesquisa Agropecuária Brasileira
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2007 EN
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The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD50 from 2.72 to 39.71 mg g-1 a.i.). The increasing order of insects susceptibility to coumarin was R. dominica...

Plant compounds insecticide activity against Coleoptera pests of stored products

MOREIRA, M.D.; PICANÇO, M.C.; BARBOSA, L.C. de A.; GUEDES, R.N.C.; CAMPOS, M.R. de; SILVA, G.A.; MARTINS, J.C.
Fonte: Pesquisa Agropecuária Brasileira, Brasília, v. 42, n.7, p. 909-915, jul. 2007 Publicador: Pesquisa Agropecuária Brasileira, Brasília, v. 42, n.7, p. 909-915, jul. 2007
Tipo: Artigo em periódico indexado (ALICE)
EN
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The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD50 from 2.72 to 39.71 mg g-1 a.i.). The increasing order of insects susceptibility to coumarin was R. dominica...

Insecticide distribution model in human tissues viewing worker's health monitoring programs

Paraíba,Lourival Costa; Castro,Vera Lúcia Scherholz Salgado de; Maia,Aline de Holanda Nunes
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2009 EN
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This work aimed at evaluating the characteristics of thirty nine insecticides on tissue distribution and accumulation, using their physico-chemical characteristics and the tissues lipid contents to calculate the compounds distribution among the tissues. The insecticides evaluated were selected among those registered in Brazil for agriculture use. The level I fugacity model was used for the calculations of insecticide distribution among the tissues of muscles, viscera, skin, fat, blood, liver, kidneys and gut. The octanol-water partition coefficient, water solubility and tissue lipid contents showed an insecticide distribution in human tissues. Cluster analysis was performed aiming the identification and separation of insecticides groups based on their physico-chemical characteristics as compounds with similar distribution within tissues and at the same time tissues with similar distribution of various insecticides. Cluster analysis pointed out three insecticide groups: in the first, 70 - 86% of insecticide accumulation was found in lipid tissues; in the second, 44 - 58%; and in the third, 9 -19%. These results could contribute to health monitoring programs of farmworkers.

Acceptability and perceived side effects of insecticide indoor residual spraying under different resistance management strategies

Rodríguez,Américo David; Penilla,Rosa Patricia; Rodríguez,Mario Henry; Hemingway,Janet; Trejo,Antonio; Hernández-Avila,Juan Eugenio
Fonte: Instituto Nacional de Salud Pública Publicador: Instituto Nacional de Salud Pública
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
Relevância na Pesquisa
36.99%
OBJECTIVE: To assess household acceptability and perceived side effects of residual indoor pyrethroid (PYR), carbamate and organophosphate insecticides sprayed by annual rotation (ROT), spatial mosaic (MOS), and a single insecticide (DDT or PYR) in communities of the coastal plain of Chiapas, Mexico. MATERIAL AND METHODS: A questionnaire to assess the acceptability and perceived side effects of indoor insecticides was administered to one member of 30% of the families in eight villages of Chiapas. The association of different insecticide treatments with their responses was evaluated (Chi-square). The intensity of side effects indicated under different treatments was compared in an ordered logistic model, using a severity index as the response variable. RESULTS: Insecticide spraying as a probable cause of symptoms was identified by 2.1% of interviewees. A significantly high percentage of persons with blurred vision, dizziness, sneezing, coughing, numbness, watery eyes, and itching lived in villages under MOS and ROT and a high severity index was significantly associated with ROT treatment. Reduction of mosquito bites and cockroaches were the perceived main benefits, and most villagers that perceived no benefits lived in DDT treated villages. Most of the interviewees welcomed spraying (83.7%)...

Acceptability and perceived side effects of insecticide indoor residual spraying under different resistance management strategies

Rodríguez,Américo David; Penilla,Rosa Patricia; Rodríguez,Mario Henry; Hemingway,Janet; Trejo,Antonio; Hernández-Avila,Juan Eugenio
Fonte: Instituto Nacional de Salud Pública Publicador: Instituto Nacional de Salud Pública
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
Relevância na Pesquisa
36.99%
OBJECTIVE: To assess household acceptability and perceived side effects of residual indoor pyrethroid (PYR), carbamate and organophosphate insecticides sprayed by annual rotation (ROT), spatial mosaic (MOS), and a single insecticide (DDT or PYR) in communities of the coastal plain of Chiapas, Mexico. MATERIAL AND METHODS: A questionnaire to assess the acceptability and perceived side effects of indoor insecticides was administered to one member of 30% of the families in eight villages of Chiapas. The association of different insecticide treatments with their responses was evaluated (Chi-square). The intensity of side effects indicated under different treatments was compared in an ordered logistic model, using a severity index as the response variable. RESULTS: Insecticide spraying as a probable cause of symptoms was identified by 2.1% of interviewees. A significantly high percentage of persons with blurred vision, dizziness, sneezing, coughing, numbness, watery eyes, and itching lived in villages under MOS and ROT and a high severity index was significantly associated with ROT treatment. Reduction of mosquito bites and cockroaches were the perceived main benefits, and most villagers that perceived no benefits lived in DDT treated villages. Most of the interviewees welcomed spraying (83.7%)...