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1.
Insects ; 14(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38132579

RESUMO

The common bean (Phaseolus vulgaris L.) is an important leguminous crop providing low-cost protein in developing countries worldwide. Insect pests are the main threats to common bean production, and this article focuses on the soybean looper (SL) Chrysodeixis includens (Walker, 1858) (Lepidoptera: Noctuidae), which feeds on leaves and pods. The recurrent use of synthetic chemicals may lead to pest resistance. Genetically resistant plants may diminish their use. Thus, the objective was to study common bean genotypes' resistance toward SL. The plants were grown in greenhouse conditions. The biology, fertility life table, oviposition preference and free-choice feeding preference were analyzed. Phenol and flavonoid content were assessed in leaves using a biology assay. Uirapuru genotype negatively affected C. includens biology and reproduction. Tangará genotype favored these parameters. Genotypes Quero-Quero, Nhambu, Corujinha, Andorinha, ANFC 9, Siriri, BRS Radiante and Verdão were more attractive for third-instar larvae. Negative correlations between phenolic and flavonoid compounds with survival rate (from egg to adult) rate were found. Common bean genotypes with dark leaves are less preferred for oviposition.

2.
Sci Total Environ ; 899: 165762, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37495148

RESUMO

The natural ecosystems' replacement by farmland and the consequent biodiversity damage (BD) for agriculture are one of the principal concerns worldwide. The development of the life cycle assessment (LCA) methodology involves enormous efforts to include BD parameters and develop a prospective LCA approach for future evaluations of production and technologies use. Thus, this work aims to determine the current impacts and estimate the future impacts in terms of damage to biodiversity caused by land occupation by agricultural commodities produced in Brazil, such as coffee, corn, oranges, and sugar cane, for the six ecoregions present in the country-Amazon, Atlantic Forest, Caatinga, Cerrado, Pampas, and Pantanal-in the 20-year period from 2015 to 2035. For this and to search for hotpots, we applied the indicators proposed by Chaudhary and Books (2018), for inventories whose functional unit is production per m2 of 1 kg of crop. Although the Cerrado is one of the ecoregions in which deforestation has advanced the most, it has the area/production ratio that has evolved the most. In contrast, Pampas and Caatinga, which are not seen as agricultural frontiers, increased their impacts. The most optimistic scenarios for the future have been those in regions considered agricultural frontiers; however, these are the regions where agriculture is more technologically developed, for example, coffee production in the Atlantic Forest and in the Cerrado. The results indicate that the technological development of agriculture can contribute to mitigating the impacts of damage to biodiversity in the future, and that the implementation of legislative and inspection measures is fundamental to supporting the correct use of the soil and preventing illegal soil change. Otherwise, in the future, we will see the increasing disappearance of species. Thus, we need researchers, farmers, and policy makers to move from development to conservation.


Assuntos
Café , Ecossistema , Animais , Brasil , Conservação dos Recursos Naturais/métodos , Biodiversidade , Agricultura/métodos , Solo , Estágios do Ciclo de Vida
3.
Environ Sci Pollut Res Int ; 30(20): 58315-58329, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36977877

RESUMO

Phytosanitary control is essential to ensure agricultural productivity and quality. However, approaches based on scheduled use of pesticides, overuse of harmful molecules produce impacts on different types of living organisms. Integrated Pest and Disease Management (IPM-IDM) may significantly reduce the burden of pesticides in the environment. Plant resistance may also be included in the IPM-IDM and even in conventional management due to little requirement of additional knowledge and changes in agricultural practices. Robust environmental assessments using methodology of universal use, life cycle assessment (LCA), may estimate the impacts of specific pesticides that cause major damages, including remarkable category impacts. Therefore the objective of this study was to determine the impacts and (eco)toxicological effects of phytosanitary strategies (IPM-IDM including or not lepidopteran resistant transgenic cultivars) vs. the scheduled approach. Two inventory modeling methods were also applied to gather information on the use and applicability of these methods. Life cycle assessment (LCA) was applied using two inventory modeling methods: 100%Soil and PestLCI (Consensus) using data from Brazilian croplands under tropical conditions, by combining phytosanitary approaches (IPM-IDM, IPM-IDM + transgenic cultivar, conventional, conventional + transgenic cultivar) and modeling methods. Hence, eight soybean production scenarios were established. The IPM-IDM was efficient to reduce the (eco)toxicity impacts of soybean production mainly for freshwater ecotoxicity category. Due to the dynamic character of IPM-IDM approaches, the inclusion of recently introduced strategies (plant resistant and biological control to stink bugs and plant fungal diseases) may diminish even more the principal impacting substances throughout the Brazilian croplands. The PestLCI Consensus method, although its development is yet in progress, to date can be suggested to estimate the agriculture environmental impacts more properly under tropical conditions.


Assuntos
Glycine max , Praguicidas , Animais , Praguicidas/toxicidade , Agricultura , Controle de Pragas/métodos , Plantas , Estágios do Ciclo de Vida
4.
Insects ; 13(8)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36005363

RESUMO

Tomato plants are highly susceptible to pests. Among the control methods, genetic improvement with introgression of resistance genes from wild accessions into commercial tomato lines is the best alternative for an integrated pest management (IPM). Thus, the objective of this study was to select tomato genotypes in advanced populations (F2BC3), with higher levels of acylsugar content, greater recurrent parent genome recovery, and resistance to Tetranychus urticae and Bemisia tabaci inherited from Solanum pennellii. For pest resistance, bioassays were assessed: nine high-acylsugar genotypes, four low-acylsugar genotypes, and the parents, Solanum lycopersicum or 'Redenção', and Solanum pennellii LA-716. Glandular and non-glandular trichomes were quantified. A negative correlation was measured between acylsugar content in the leaflets and pest behavior. Pest resistance was found in the selected F2BC3 genotypes with high-acylsugar content, indicating that this allelochemical was efficient in controlling the arthropod pests.

5.
Bull Entomol Res ; 112(3): 389-398, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35543299

RESUMO

Non-crop plant diversity plays a fundamental role in the conservation of predatory mite (PM) and can be proposed as a banker plant system (BPS). BPSs provide plants that host natural enemies in greenhouses or field crops and may improve the efficiency of biological control. The aim of this study was to investigate if a diverse plant composition could be a suitable BPS for PMs in strawberry crops. A plant inventory characterized 22 species of non-crop plants harboring PMs. The most abundant PMs, in decreasing order, were Neoseiulus californicus, Neoseiulus anonymus, Euseius citrifolius, and Euseius concordis. PMs were randomly distributed among plants. We also found specific associations of Phytoseiidae species and phytophagous or generalist mites on plants. Due to this, four species were deemed suitable as banker plants: Capsicum sp., Leonurus sibiricus, Solanum americanum, and Urochloa mutica. Moreover, these plants combined a high PMs density and a low occurrence or absence of pest-mites. This study suggests shifting the traditional view that BPSs are composed of a limited number of species to use plant assemblages. This contributes to both conservation and augmentative biological control.


Assuntos
Fragaria , Ácaros , Tetranychidae , Animais , Controle Biológico de Vetores , Comportamento Predatório
6.
Insects ; 12(10)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34680680

RESUMO

The broad mite (BM) Polyphagotarsonemus latus is a pest of great prominence for several crops, including the common bean (Phaseolus vulgaris). The objective of this study was to select resistant genotypes and to determine chemicals associated with resistance. In the first experiment, BM incidence was assessed for 36 genotypes in a greenhouse study. A group of 10 genotypes was selected according to the development of BM populations. Mite populations and phytometric and biochemical variables were then determined to study eventual differential genotypic responses to mite infestation. Lower numbers of mite mobile forms (larvae + adults) were found on Verdão, Negrão and Carioca Original genotypes. The magnitude of differences reached 5.4 times more BM in the IAC Alvorada than the Verdão genotype. Plant yields were reduced for the genotypes TAA Bola Cheia, IPR Sabiá, IPR Uirapuru, IAC Alvorada and Carioca Original when plants were infested with BM. The yields for LP 13833, BRS Esteio, Negrão 11, Verdão and MD 1133 were similar between infested and non-infested genotypes, indicating tolerance. Verdão and Negrão 11, besides the tolerance, exhibited low offspring development, indicating antibiosis and/or antixenosis. Higher phenolic compound levels were found in the Verdão genotype. Increased contents of catalase and peroxidase were detected for Negrão 11 genotype when infested with BM. This work allowed the detection of common bean genotypes that express resistance and tolerance to BM. These genotypes can be used in places with a history of BM infestation, or used in breeding programs to incorporate these characteristics in other genotypes.

7.
Neotrop Entomol ; 50(4): 605-614, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33876392

RESUMO

Environmental variables may markedly influence egg parasitoid performance and must be considered when choosing the best release strategy. Thus, this study aimed to investigate the effects of light, temperature, soil moisture, and precipitation on the emergence and parasitism of parasitoid releases of unprotected and encapsulated pupae. The presence of light favored the parasitism of Trichogramma pretiosum Riley, 1879, and Telenomus remus (Nixon, 1937) but did not impact the parasitism of Telenomus podisi (Ashmead, 1893). The release strategy adopted (release of encapsulated or unprotected pupae) also impacted the results. On one hand, card capsules gave protection against rainfall, limited to 10 mm regarding Tr. pretiosum, while on the other hand, card capsules led to a reduction in the number of captured adults for Te. podisi at 25°C and 30°C. Therefore, Tr. pretiosum, Te. remus, and Te. podisi can be released using both encapsulated and unprotected pupae, with advantages and disadvantages for each strategy, depending on each studied environmental variable. In addition, parasitoid pupae should be released so that the majority emerge during daylight, especially for Te. remus and Tr. pretiosum, since parasitism was greatly reduced in dark environments. Telenomus podisi is not affected by this variable as it demonstrated similar parasitism in light and dark environments.


Assuntos
Himenópteros , Animais , Himenópteros/parasitologia , Luz , Pupa , Chuva , Temperatura
8.
Braz. arch. biol. technol ; 61: e18180028, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974111

RESUMO

ABSTRACT Extracts of the seeds of Tephrosia vogelii Hook. f. were studied in relation to its chemical composition and toxicity to the brown stink bug Euschistus heros (F.). The extracts were obtained in ethyl acetate and ethanol in the sequence according to the polar nature of the solvents. Extracts were sprayed in concentration of 1.0, 2.5, 5.0, 7.5 and 10% on third-instars nymphs and adults, and mortality was recorded. Presence two rotenoids in ethyl acetate was detected, with analyzed with gas chromatography-mass spectrometry (GC-MS). Crude fraction analyses confirmed the presence of these rotenoids (tephrosin - 2.71% in ethyl acetate and 3.66% in methanol; and deguelin - 10.46% in ethyl acetate and 1.22% in methanol) and three other rotenoids in small amounts. Eight days after applications, ethyl acetate caused more stink bugs mortality and on less time than ethanol extract, because great quantity of rotenoids, as polarity. Concentrations above to 1 and 2.5% of the ethyl acetate extracts caused mortality above 80% of the nymphs and adults of E. heros, respectively. Concentration were considered high, thus chemist analyzes demonstrated high rotenoids presence. In conclusion, seed T. vogelli extracts, rich in deguelin and tephrosin (3:1), cause mortality of E. heros, however, high concentration are necessary.


Assuntos
Glycine max , Cimicidae , Tephrosia/química , Glicina
9.
Ciênc. rural (Online) ; 48(3): e20160863, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-1045079

RESUMO

ABSTRACT: The infestation of coffee leaf miner and its predation by wasps were assessed in commercial organic coffee plantings shaded with leucaena or intercropped with pigeon pea. Plantings in northern Paraná were assessed every two weeks from June 2011 to December 2012. The percent of infested leaves, number of mines per leaf and the percent of predation by wasps (indicated by lacerations) were determined. Fewer coffee leaf miners and fewer mines per leaf were found in pigeon pea intercropped plantings (28.4% and 0.3, respectively) than in shaded plantings with leucaena (48.1% and 0.8, respectively). More predation by wasps was found in the shaded (27.2%) than in the intercropped (13.2%) plantings. Suggestions for new studies are presented along with suggestions for managing the leaf miner in coffee plantings.


RESUMO: A infestação de bicho-mineiro e a sua predação por vespas foram avaliadas em lavouras comerciais de café orgânico sombreadas com leucena ou consorciadas com feijão guandu. As lavouras situadas na região Norte do Paraná foram avaliadas a cada duas semanas de junho de 2011 a dezembro de 2012. Determinou-se o percentual de folhas infestadas, o número de minas por folha e a porcentagem de predação por vespas (indicada pela laceração das minas). Menor infestação do Bicho-mineiro e o menor número de minas por folha foi verificada na lavoura consorciada com feijão guandu (28,4% e 0,3; respectivamente) em relação a lavoura sombreada com leucina (48,1% e 0,8; respectivamente). Maior predação por vespas foi verificada na lavoura sombreada (27,2%) em relação a lavoura consorciada (13,18%). Sugestões de novas pesquisas e para o manejo do bicho-mineiro em lavouras de café são apresentadas.

10.
Ciênc. rural ; 44(11): 1908-1914, 11/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-728740

RESUMO

Strawberry fields receive several pesticides spraying and residues in fruits are recurrent. Development and application of methods that avoid applying pesticides mostly during fructification period are imminent needs. Comparison of population of two-sppoted spider mite (TSSM) Tetranychus urticae Koch. in organic and mineral fertilized plants (as used by growers) and treated with alternative products were done. Plants were grown in vessels in a greenhouse infested with local population of TSSM. Extracts of Tephrosia voggeli (Hook), neem oil (Azadirachta indica A. Juss.), and lime sulfur were applied three times against TSSM in ten days intervals. Assessments were done three times after each spraying. Interaction between fertilization and spraying alternatives was also assessed but was not significant. TSSM population was about 44% lesser in organic fertilized plants than those in inorganic fertilized. T. voggeli extracts reduced in large amounts TSSM; neem oil reduced in some assessments and an intermediate reduction was found for sulfur lime. Organic fertilization and T. voggeli extracts are potential strategies to manage TSSM and additional studies are proposed to enable wide utilization.


Lavouras de morango recebem várias aplicações de agrotóxicos e resíduos nos frutos são recorrentes. O desenvolvimento e a aplicação de métodos de manejo que evitem a aplicação de pesticidas, principalmente durante o período de frutificação, é uma necessidade iminente. Compararam-se as populações do ácaro rajado Tetranychus urticae Koch. em plantas adubadas com fertilizantes orgânicos e minerais (como o usados por produtores) e tratadas com produtos alternativos. As plantas foram cultivadas em vasos, em casa de vegetação infestada de população local do ácaro. Extratos de Tephrosia voggelii (Hook), óleo de nim (Azadirachta indica A. Juss.) e calda sulfocálcica foram pulverizados três vezes em intervalos de 10 dias. As avaliações foram realizadas três vezes após cada pulverização. A interação entre a fertilização e produtos alternativos em pulverização foi também avaliada, mas não foi significativa. A população do ácaro foi cerca de 44% menor em plantas fertilizadas com fertilizante orgânico do que aquelas com fertilizante mineral. Extrato de T. voggelii reduziu em grande quantidade a população do ácaro; o óleo de nim reduziu em algumas avaliações e redução intermediária foi observada com calda sulfocálcica. Adubação orgânica e extrato de T. voggeli são estratégias potenciais para manejar a população de ácaros e estudos adicionais são propostos para permitir ampla utilização.

11.
Neotrop Entomol ; 41(5): 404-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23950091

RESUMO

The maize weevil Sitophilus zeamais Motsch. is an important pest of maize that attacks the grain both in the field and during storage. The damage caused by the maize weevil S. zeamais on maize landraces, Amarelo Antigo, Asteca, Caiano, Carioca, and Ferrinho, was evaluated by no-choice tests under laboratory conditions. The commercial varieties Sol da Manhã, BR 106, BR 451, and the synthetics PC 0203 and PC 9903 were evaluated for comparisons with the maize landraces. The parameters evaluated were susceptibility index, number of weevil progeny, development time, weevil progeny dry weight, and grain dry weight loss. The landraces were more susceptible to the maize weevil as compared to the commercial varieties. Based on the cluster analysis, two groups of susceptibility to the maize weevil were observed: one of more susceptible populations formed by local landraces and BR 451, and another less susceptible, with commercial varieties, synthetics, and the landrace Amarelo.


Assuntos
Imunidade Vegetal , Gorgulhos/fisiologia , Zea mays/fisiologia , Zea mays/parasitologia , Animais , Zea mays/classificação
12.
Ciênc. rural ; 40(7): 1497-1501, jul. 2010. tab
Artigo em Inglês | LILACS | ID: lil-557035

RESUMO

The Mexican bean weevil Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae) is an important pest of stored beans in tropical regions. The efficiency of kaolin [with or without neem (Azadirachta indica) oil] and diatomaceous earth (DE) (standard treatment) was studied in laboratory aiming to obtain alternatives for chemical control of this insect. Insects were confined in plastic vials containing beans treated with kaolin (2, 4 and 8g kg-1), kaolin + neem [2g kg-1(5 percent neem oil)], diatomaceous earth (1g kg-1) and control. Mortality of adult insects, number of eggs and F1generation beetles emergency were assessed. Kaolin caused mortality of Z. subfasciatus, however higher periods and doses than DE were necessary to promote high mortality (100 percent or close). Kaolin treatments also affected female behavior because many eggs were placed in the vials walls. Number of emerged adults (F1) was similar between DE and kaolin; hence, kaolin constitutes a promising tool to the management of Z. subfasciatus. The mixture of kaolin and neem oil was not efficient in the control of Z. subfasciatus.


O caruncho-do-feijão Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae) é uma importante praga de grãos de feijão armazenado nas regiões tropicais. A eficiência do caulim [com ou sem óleo de nim (Azadirachta indica)] e terra diatomácea (TD) (tratamento padrão) foi estudada em laboratório com o intuito de obter alternativas para o controle químico deste inseto. Insetos foram confinados em frascos de plástico com feijão tratado com caulim (2, 4 e 8g kg-1), caulim + nim [2g kg-1(5 por cento óleo de nim)], terra diatomácea (1g kg-1) e controle. Mortalidade de insetos adultos, número de ovos e emergência da geração F1 foram avaliados. Caulim causou a mortalidade de Z. subfasciatus, porém foram necessários maiores períodos e doses que a TD para promover elevada mortalidade (100 por cento ou aproximadamente). Os tratamentos com caulim também afetaram o comportamento da fêmea, pois muitos ovos foram colocados nas paredes dos frascos. O número de adultos emergidos (F1) foi similar entre a TD e o caulim; portanto, caulim constitui uma ferramenta promissora para o manejo de Z. subfasciatus. A mistura de caulim e óleo de nim não foi eficiente no controle de Z. subfasciatus.

13.
Braz. arch. biol. technol ; 52(6): 1333-1340, Nov.-Dec. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-539099

RESUMO

Several synthetic and commercial analogs of 1,4-dimethoxybenzene, a kairomone of Diabrotica speciosa, along with other compounds already shown to be attractive to other species of Diabrotica, were tested as attractant to D. speciosa. Yellow cup traps were lured with the compounds and installed in a common bean field. Assessments were conducted 24 h later. 1,4-dimethoxybenzene lured traps caught significantly more beetles than the control traps. Captures of traps lured with 1,4-dimethoxybenzene analogs did not differ from the control traps. Results showed that position and nature of the substituents on the aromatic ring played a crucial role in the activity of the natural compound. The aromatic ring was also very important to the activity of the kairomone.


Uma série de compostos, sintéticos e comerciais, análogos ao 1,4-dimetoxibenzeno, um cairomônio de Diabrotica speciosa, juntamente com outros compostos comerciais atrativos para outras espécies de Diabrotica, tiveram suas atividades testadas frente à D. speciosa. Armadilhas de copos amarelos contendo os compostos foram instaladas em plantação de feijão. As avaliações foram realizadas 24 horas depois. Armadilhas com 1,4-dimetoxibenzeno capturaram significativamente mais insetos do que armadilhas testemunha. Armadilhas com análogos do 1,4-dimetoxibenzeno não capturaram mais insetos que as armadilhas testemunha. Os resultados mostraram que a posição e a natureza dos substituintes, juntamente com a aromaticidade verificada na estrutura do composto natural, são cruciais para a atratividade.

14.
Braz. arch. biol. technol ; 51(6): 1121-1126, Nov.-Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-504033

RESUMO

The effects of concentrations (0.00, 0.25, 0.50 and 1.00 percent) of the neem tree (Azadirachta indica - Meliaceae) oil emulsion on the behavioral and biological parameters of M. punctigera were investigated in the laboratory. Wild radish (Raphanus raphanistrum L.) host plant was used. Multiple and no-choice feeding preference assays were conducted which shown multiple effects. The males were repelled by the neem oil in multiple-choice assay. The adult (multiple-choice) and larvae (multiple and no-choice) feeding were deterred. The larvae mortality was higher in the neem oil treated than the control leaves. Further investigations are suggested to test neem oil in the management of the pest in the field.


Besouros Microtheca punctigera (Achard) são pragas sérias de plantas hospedeiras da família Brassicaceae. Efeitos das concentrações (0,00; 0,25; 0,50; e 1,00 por cento) do óleo emulsionável de nim (Azadirachta indica Meliaceae) sobre parâmetros de comportamento e biologia de M. punctigera foram investigados em laboratório. Nabiça (Raphanus raphanistrum L.) foi a planta hospedeira utilizada. Ensaios de preferência alimentar com múltipla e sem chance de escolha foram conduzidos. Múltiplos efeitos do óleo de nim foram observados. Machos foram repelidos pelo óleo de nim em teste de múltipla escolha. Adultos (múltipla escolha) e larvas (múltipla e sem chance de escolha) sofreram deterrência. A mortalidade de larvas foi mais elevada nos tratamentos com óleo de nim que no tratamento controle. Futuras investigações são sugeridas para testar o óleo de nim no manejo de pragas no campo.

15.
Ciênc. rural ; 38(8): 2119-2123, Nov. 2008. tab
Artigo em Português | LILACS | ID: lil-511987

RESUMO

Diabrotica speciosa (Germar, 1824) (Coleoptera: Chrysomelidae: Galerucinae) é uma importante praga polífaga na América Latina. Seu controle é realizado com inseticidas sintéticos, o que causa problemas ambientais. Desse modo, o objetivo do trabalho foi avaliar a isca amilácea de cucurbitacina (Lagenaria vulgaris L.) associada ao inseticida carbaril no controle de D. speciosa em laboratório. Foram realizados testes de múltipla escolha pareados e confinamento com insetos adultos. Os tratamentos foram: isca amilácea de cucurbitacina, isca + carbaril, apenas carbaril e a testemunha (água destilada). As soluções foram pulverizadas em plantas de milho mantidas em casa-de-vegetação. Folhas foram retiradas para realização dos ensaios em laboratório e sete avaliações (três, cinco, sete, dez, 12, 14 e 17 dias após a aplicação) foram realizadas. Foram avaliados o consumo foliar e a mortalidade. A isca de cucurbitacina exerceu efeito fagoestimulante aos adultos de D. speciosa. A adição da isca ao carbaril aumentou a eficiência do inseticida.


Diabrotica speciosa (Germar, 1824) (Coleoptera: Chrysomelidae: Galerucinae) is an important polyphagous pest in Latin America. The control is made using synthetic insecticides, which cause environmental problems. Then, objective this work was to study the cucurbitacin (Lagenaria vulgaris L.) starch based associated with carbaril insecticide for D. speciosa control, in the laboratory. Multiple-choice and no-choice tests with adult insects were realized. The treatments were: cucurbitacin starch based bait, cucurbitacin starch based bait plus carbaril insecticide, insecticide carbaril alone and control (distillated water). Corn plants were sprayed with insecticide solutions in greenhouse and leaves were removed. Leaves were offered to insects and seven evaluations (three, five, seven, ten, 12, 14 and 17 days after applied) were achieved. Feeding leaf area and mortality were evaluated. Cucurbitacin starch based bait elicited phagostimulant effect on adults of D. speciosa. Addition of cucurbitacin starch based bait on carbaril insecticide increased insecticide efficiency.

16.
Ciênc. rural ; 37(3): 623-627, jun. 2007. tab, graf
Artigo em Português | LILACS | ID: lil-450221

RESUMO

Doru luteipes consome lagartas de Spodoptera frugiperda, que é atualmente a principal praga da cultura do milho no Brasil. Normalmente, se 70 por cento das plantas tivessem o predador, a praga seria mantida abaixo do nível de dano econômico. Entretanto, o predador ocorre após a praga danificar as plantas. Assim, a disponibilidade de materiais que atraíssem e antecipassem a presença do predador na lavoura poderia reduzir populações da praga. Desta forma, estudou-se em laboratório a atratividade de dietas artificiais para machos e fêmeas do predador D. luteipes. Os tratamentos foram: pupa desidratada e moída do bicho-da-seda; pólen misto, nas quantidades de 0,05; 0,1; 0,2; 0,5 e 1,0g para ambas as dietas. Em olfatômetro, os estímulos da dieta foram comparados à testemunha. Foram realizadas 30 repetições. Os resultados mostraram que houve atratividade tanto para machos quanto para fêmeas. Em geral, a atração foi aumentada com o aumento da quantidade das dietas. Estudos adicionais foram propostos para testar a viabilidade do uso dos materiais como estratégia de manejo da praga no campo.


Doru luteipes consumes larvae of Spodoptera frugiperda, which is at this moment the main pest of maize crop in Brazil. In general, if 70 percent of the plants had this predator the pest would be kept under the threshold of economic damage. However, the predator occurs after the pest damages the plants. Thus, the availability of materials that would attract and anticipate the presence of predator in the field,could reduce pest populations. In such a way, it was studied in the laboratory the attractiveness of artificial diets for males and females of the D. luteipes. The treatments were: ground dehydrated pupa of the silk worm and pollen mixture in the amounts of 0.05, 0.1, 0.2, 0.5 e 1.0g, for both the diets The diet stimulus were compared to control using a olfactometer. In general, attraction increased with rising amounts of the diets. Further investigations were proposed to test the viability of the usage of the materials to manage the pest in the field.

17.
Braz. arch. biol. technol ; 49(6): 975-980, Nov. 2006. tab, graf, ilus
Artigo em Inglês | LILACS | ID: lil-443148

RESUMO

Responses of Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) to a semiochemical trap characteristics were investigated in the field. The trap consisted of plastic bottles with several perforations (0.5 cm diameter and 2.0 cm distance each other) and containing Lagenaria vulgaris L. (Cucurbitaceae) powder as cucurbitacin (arrestant and phagostimulant) source (0.28 percent). In common bean fields, transparent green traps caught significantly more males and females beetles than yellow, transparent and white traps. Yellow traps caught significantly more females than white traps. Transparent green and yellow traps baited with the volatile attractant 1,4-dimethoxybenzene caught 4.08 and 2.72 times more beetles than unbaited, respectively. Higher number of beetles was caught by 2L bottle traps than 1, 0.5 and 0.25 mL. In corn fields, transparent green bottle traps caught significantly more beetles in Campo Mourão and similar captures were found in Londrina field.


Respostas de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) a características de uma armadilha contendo semioquímicos foram investigadas no campo. As armadilhas consistiam de garrafas plásticas com vários orifícios (0,5cm de diâmetro e 2 cm de distância entre eles) e continham pó de Lagenaria vulgaris L. (Cucurbitaceae) como fonte de cucurbitacina (arrestante e fagoestimulante) (0,28 por cento). No feijão comum, armadilhas verdes transparentes capturaram significativamente mais insetos machos e fêmeas que armadilhas amarelas, transparentes e brancas. Armadilhas amarelas capturaram significativamente mais fêmeas que armadilhas brancas. Armadilhas verdes transparentes e amarelas com o atraente volátil 1,4-dimetoxibenzeno capturaram 4,08 e 2,72 mais insetos do que aquelas sem o volátil, respectivamente. Maior número de insetos foi encontrado em armadilhas confeccionadas em garrafas de 2000 mL do que em garrafas de 1000, 500 e 250 ml. Em campos de milho, armadilhas verdes transparentes capturaram mais insetos em Campo Mourão e similar número foi encontrado em Londrina.

18.
Semina ciênc. agrar ; 27(1): 43-46, jan.-mar. 2006.
Artigo em Português | LILACS | ID: lil-453115

RESUMO

Testes de múltipla escolha foram realizados para comparar a preferência alimentar de Diabrotica speciosa (Ger.) por folhas de brócolos (Brassica oleraceae L. var.italica) cultivado em sistema natural, convencional e orgânico. No sistema natural de cultivo houve a incorporação de capim elefante Pennisetum purpureum Schumacher cv.Napier (50 ton/ha), composto Bokashi (1,5 ton/ha) e pulverização de EM 4 (Natural 1), ou a incoporação do composto Bokashi (1,5 ton/ha) e pulverização do EM 4 (Natural 2), no sistema convencional houve a incorporação do NPK+borax+N em cobertura, e no sistema orgânico incorporou-se composto orgânico (1 kg/planta). O composto orgânico foi preparado utilizando-se resíduos de milho (Zea mays L.) e soja [Glycine max (L.) Mer.] e esterco de gado. Folhas foram retiradas das plantas das quais foram separados discos, e colocados em gaiolas em testes de múltipla escolha. Os insetos preferiram folhas do sistema convencional. A alimentação nas folhas do sistemas Natural 1, Natural 2 e Orgânico foi 68, 67 e 57 daquela registrada nas folhas do sistema convencional de cultivo


Multiple-choice laboratory tests were achieved to compare feeding preference of Diabrotica speciosa(Ger.) to leaves of broccoli (Brassica oleraceae L. var. italica) from natural, conventional and organicfarming systems. Natural farming systems included incorporation of the elephant grass Pennisetumpurpureum Schumacher cv. Napier (50 ton/ha), Bokashi compost (1.5 ton/ha) and spray of EM 4 (Natural1), or the incorporation of the Bokashi compost (1.5 ton /ha) and spray of EM 4 (Natural 2), and in theconventional, NPK + borax were incorporated in the planting + dressing N and organic compost (1 kg/plant) was incorporated in the organic system. Organic compost was prepared using crop residues ofcorn (Zea mays L.), soybean [Glycine max (L.) Mer.], and cattle manure. Leaf discs were collected andplaced in cages in multiple-choice tests. Beetles preferred mostly broccoli leaves from conventionalfarming system than leaves from Natural (1 and 2) and Organic farming systems. Feeding on leaves fromNatural 1, Natural 2 and Organic farming system were 68, 67 and 57% of the feeding on leaves fromConventional farming system


Assuntos
Agricultura Orgânica/métodos , Agricultura Urbana
19.
Ciênc. rural ; 35(5): 981-985, set.-out. 2005. tab
Artigo em Português | LILACS | ID: lil-416167

RESUMO

As respostas de larvas de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) ao CO2 e o comportamento destas larvas quando expostas a plantas hospedeiras e não hospedeiras foram estudadas em laboratório. Larvas de primeiro ínstar de D. speciosa foram utilizadas. Num primeiro bioensaio, as larvas preferiram o tratamento com CO2, que foi gerado a partir da reação de bicarbonato de potássio com ácido acético em oposição a água destilada. Quando se observou o comportamento das larvas em relação a plantas hospedeiras, verificou-se que ocorreu um número significativamente maior de "mudanças de direção" em milho e milho pipoca do que em feijão, soja, trigo e sorgo. Este parâmetro foi inferior no sorgo em relação a todos os outros tratamentos. Valores similares foram verificados em milho pipoca e milho (26,2 e 24,2, respectivamente). Em relação a distância percorrida, foram verificadas maiores distâncias na aveia em comparação com milho pipoca, milho, feijão e sorgo. Após o contato das larvas com sorgo, elas não apresentaram comportamento de busca, pois a larva caía da plântula ou não se movia .

20.
Braz. arch. biol. technol ; 48(4): 589-597, July 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-410056

RESUMO

A morfologia externa dos sensilos de adultos de Neomegalotomus parvus (Westw.) (Het.: Alydidae), incluindo poros e pontos permeáveis na cutícula, foi estudada em microscópio eletrônico de varredura, em relação à função olfativa. A evidência comportamental do olfato e a importância dos diferentes segmentos antenais na localização do hospedeiro, em condições de ausência de movimentação do ar, foram também estudados. Sensilos mecanoreceptores foram observados nos quatro segmentos da antena de N. parvus, sendo no entanto, a densidade maior no quarto segmento. Nos segmentos apicais, foram observados sensilos com características morfológicas olfativas. Percevejos com antenas intactas localizaram o alimento com mais freqüência e rapidez do que aqueles com antenas bloqueadas ou amputadas. Adultos de N. parvus preferiram sementes intactas do que aquelas vedadas com Parafilm®, mas não apresentaram preferência quando o último segmento da antena foi bloqueado. Em túnel de vento, os percevejos foram atraídos para sementes e vagens maduras, e para extrato hexânico de vagens maduras de guandu, Cajanus cajan (L.) Millsp.; não houve resposta para panículas de arroz, Oryza sativa L. (planta não hospedeira) ou para feromônio extraído de machos.

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