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Tomato severe rugose virus (ToSRV) e Tomato chlorosis virus (ToCV): relações com a Bemisia tabaci biótipo B e eficiência de um inseticida no controle da transmissão do ToSRV / Tomato severe rugose virus (ToSRV) and Tomato chlorosis virus (ToCV): relashionship with Bemisia tabaci biotype B and efficiency of an insecticide to control the transmission of ToSRVDebora Maria Sansini Freitas 28 September 2012 (has links)
A cultura do tomateiro (Solanum lycopersicum L.) é importante mundialmente devido ao alto consumo de seus frutos. Nos últimos anos surgiram nesta cultura no Brasil alguns vírus emergentes com altas taxas de disseminação, como begomovírus e crinivírus, transmitidos pela Bemisia tabaci biótipo B, que podem causar danos à produção do tomateiro. A espécie de begomovírus atualmente mais encontrada no Brasil, em plantios de tomateiro, é o Tomato severe rugose virus (ToSRV). De 2002 a 2004, pesquisadores relataram incidências desse vírus em mais da metade das amostras com sintomas de geminiviroses coletadas em vários estados brasileiros e sua presença continua sendo verificada frequentemente. No ano de 2006, um crinivírus, o Tomato chlorosis virus (ToCV), foi relatado no Brasil, infectando plantas de tomate no Estado de São Paulo e atualmente encontra-se presente em diveros estados brasileiros. Os objetivos desse trabalho foram: determinar os períodos mínimos de acesso à aquisição e à inoculação do ToSRV e do ToCV pela B. tabaci biótipo B; identificar o período de retenção do ToSRV no inseto e a interação do ToSRV e do ToCV na aquisição e na transmissão por esse aleirodídeo. Também foi avaliada a eficiência do inseticida cloridrato de cartape no controle da disseminação primária e secundária do ToSRV pela B. tabaci biótipo B em tomateiros em gaiolas em casa de vegetação. Finalmente avaliou-se a eficiência do aleirodídeo Trialeurodes vaporariorum na transmissão de um isolado brasileiro do ToCV. Os períodos mínimos de acesso à aquisição e à inoculação de ambos os vírus pela B. tabaci biótipo B foram de cinco minutos. O tempo de retenção do ToSRV em B. tabaci biótipo B foi de 25 dias. A eficiência de um único adulto de B. tabaci na transmissão simultânea do ToSRV e do ToCV para tomateiros foi de 44,7%, similar àquela da transmissão isolada do ToRSV (47,4%) e do ToCV (44,7%). A eficiência de T. vaporariorum na transmissão do ToCV foi inferior à da B. tabaci biótipo B. Usando 40 insetos por vaso com duas plantas as eficiências de transmissão foram 57,7% e 100%, respectivamente. O inseticida cloridrato de cartape reduziu a infecção secundária do ToSRV pela B. tabaci biótipo B, mas não foi eficiente para reduzir a infecção primária em tomateiros. / Tomato (Solanum lycopersicum) is one of the leading vegetables grown and consumed in Brazil and in the world, after potato. The importance of tomato is related to its high consumption worldwide and also its nutritive value. Presently the most important virus diseases responsible for yield losses on tomato crops in Brazil are those caused by begomovirus and crinivirus, both transmitted by Bemisia tabaci biotype B. At the moment the prevalent species of begomovirus is Tomato severe rugose virus (ToSRV). From 2002 to 2004, researchers reported incidence of this virus in more than half of the symptomatic tomato samples collected in several Brazilian states. In 2006, a crinivirus, Tomato chlorosis virus (ToCV), was reported for the first time in Brazil, infecting tomato plants in the State of São Paulo and at present the virus occurs in several Brazilian states. The objectives of this study were to determine the minimum acquisition and inoculation access periods of ToSRV and ToCV by B. tabaci biotype B; identify the retention period of ToSRV in the insect; and the interaction of ToSRV and ToCV on the transmission by this aleyrodidae. It was also evaluated the effectiveness of the insecticide cartap hydrochloride in controlling the primary and secondary spread of ToSRV by B. tabaci biotype B on tomato plants in a greenhouse. Finally, it was evaluated the efficiency of Trialeurodes vaporariorum in the transmission of a Brazilian isolate of ToCV. The minimum acquisition and inoculation access periods for both viruses by B. tabaci biotype B were five minutes. The maximum retention time of ToSRV in B. tabaci biotype B was 25 days. The efficiency of a single adult of B. tabaci to simultaneously transmit ToSRV and ToCV to tomato plants was 44.7%, similar to the transmission of ToRSV (47.4%), and ToCV (44.7%) separately. T. vaporariorum was less efficient than B. tabaci on the transmission of ToCV. Using 40 insects per pot with two plants, transmission efficiencies were 57.7% and 100%, respectively. The insecticide cartap hydrochloride reduced secondary infection of ToSRV transmitted by B. tabaci biotype B, but was not effective in reducing the primary infection in tomato.
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Qualidade de sementes de milho híbrido tratadas com inseticidas, armazenadas em duas condições de ambiente / Quality of hybrid maize seeds treated with agrochemical, stored in two ambient conditionsTonin, Rosane Fátima Baldiga 18 March 2008 (has links)
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Previous issue date: 2008-03-18 / The treatment of seeds is a practice widely disseminated in the Brazilian
agricultural areas, which, linked to other cultural practices, has contributed to the
increase in productivity, costs reduction, final product improvement, reduction of
damage to the environment and also offers a good protection for seeds, in the field
level as well as in storage. The objective of this paper is to check the effect of the
seed treatment of three maize hybrids on seedling emergence (stand), performance
in storage, germination and seed vigor. The seeds were treated with three
insecticides: Insecticide one (Thiametoxan - Cruiser 350 FS ® ); Insecticide two
(Neonicotinóide) and Insecticide three [Neonicotinóide+(Imidaclopride+Thiodicarbe)],
with 60,000 seed per 120ml of insecticide. After being treated, the seeds were stored
for a period of 270 days, in two environments. One with (10°C) temperature control
and relative humidity (60%) and the other one under normal conditions of storage.
During this period, 45 in 45 days evaluations were accomplished, through
germination and vigor tests. In addition to germination and cooling tests, sanitation
analysis, seedling emergency and seed inoculation was carried out. The results
obtained allow concluding that the maintenance of quality seeds of hybrid maize,
treated with insecticides, depend on the hybrid and chemical product used in their
treatment and that the reduction in feasibility and vigor of seeds treated with
thiametoxan (Cruiser 350 FS ® ) is intensified due to the storage period extension. / O tratamento de sementes é uma prática largamente difundida nas áreas
agrícolas brasileiras, a qual, associada às demais práticas culturais, tem contribuído
para o incremento na produtividade, redução de custos, melhoria da qualidade do
produto final, redução de danos ao ambiente e oferta uma boa proteção às
sementes, tanto em nível de campo quanto no armazenamento. Objetivou-se
verificar o efeito do tratamento de sementes de três híbridos de milho sobre a
emergência de plântulas (estande), desempenho no armazenamento, germinação e
vigor das sementes. As sementes foram tratadas com três inseticidas, identificados
como: Inseticida 1 (Thiametoxan - Cruiser 350 FS ® ); Inseticida 2 (Neonicotinóide) e
Inseticida 3 [Neonicotinóide+(Imidaclopride+Thiodicarbe)], com dosagem de
120mL/60.000 sementes. Após tratadas as sementes foram armazenadas por um
período de 270 dias, em dois ambientes, sendo um com controle de temperatura
(10ºC) e umidade relativa (60%) e outro em condições normais de armazenamento.
Durante este período realizou-se avaliações de 45 em 45 dias, através dos testes de
germinação e vigor. Além dos testes de germinação e teste de frio foi realizado
análise sanitária, emergência de plântulas e inoculação de sementes. Os resultados
obtidos permitem concluir que a manutenção da qualidade das sementes de milho
híbrido tratadas com inseticidas depende do híbrido e do produto químico
empregado no tratamento das mesmas e que a redução na viabilidade e no vigor de
sementes tratadas com thiametoxan (Cruiser 350 FS ® ), intensifica-se com o
prolongamento do período de armazenamento.
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Avaliação de inseticidas para o controle de Aryrotaenia sphaleropa (Meyrick,1909) (Lepidoptera : Tortricidae) na cultura da videira e Efeitos secundários sobre Trichogramma pretiosum (Riley,1879) (Hymenoptera : Trichogrammatidae) / Evaluation of organic insecticides for the control Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera:Tortricidae) control in vineyards and secondary effects on Trichogramma pretiosum (Riley, 1879) (Hymenoptera:Trichogrammatidae).Morandi Filho, Wilson José 13 April 2008 (has links)
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Previous issue date: 2008-04-13 / The Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera:Tortricidae) is often found damaging
vineyards and other temperate fruit orchards, in the Serra Gaucha region. This work was
conducted to study seasonal occurrence of A. sphaleropa adults in vineyards using sexual
synthetic pheromone, the effect of commercial formulations of insecticides with emphasis on that
allowed in the organic production (neem, natural piretro, pirolenhoso extract and Bacillus
thuringiensis) to control A. sphaleropa and their effects on the egg parasitoid Trichogramma
pretiosum adults. Based on weekly evaluation A. sphaleropa adults catched in Delta trap baited
with synthetic sexual pheromone (Z11,13-14Ac + Z11,13-14Al + Z11-14Al in a ratio of 4:4:1,
1000μg/septum) during 2003/2004 season, it was observed four populational peaks in a Cabernet
Sauvignon vineyards. The first population peak occurred in the beginning of October, the second
in the beginning of February, the third occurred in middle of March and the forth in June. In the
experiments conducted in the laboratory using grapevine leaves with artificial infestations of 3st to
4th instars) and in commercial vineyard, Bacillus thuringiensis var. kurstaki (Dipel DF 50, 75 and
100 g/100L), fenitrothion (Sumithion 500 CE, 150 mL/100L) and triclhorfon (Dipterex 500, 300
mL/100L) were efficient to control A. sphaleropa larvae reducing insect population upper to 90%.
In laboratory, the insecticides Natuneem® (1500 ppm of azadirachtin/L) and the pirolenhoso
extract (Biopirol 7 M®) (250 and 500 mL/100L) were not efficient in the control of A. sphaleropa
when applied over grapevine leaves. Natural piretro (250 and 500 mL/100L) resulted in a
mortality of 77,65 and 85,88% of insects, respectively 120 hours after application. Natuneem®
(0,25 e 0,50%) incorporated to A. sphaleropa artificial diet increased larval phase, reduced larval
and pupae viability producing males with a reduces lifespan. Biopirol 7M® in the concentration of
0,50% increased larval duration, reduced male longevity and the oviposition period without
affecting fecundity. Baseding on the fertility life table, it was verified that Natuneem® and
Biopirol®, both in 0,25 and 0,50% added to artificial diets increase modified the duration in days
of a generation, the liquid tax of reproduction, the infinitesimal reason of population increase and
the finite reason of increase of A. sphaleropa, when compared with diet without insecticides.
Secondary effects of insecticides allowed in organic production (Natuneem®, natural piretro,
Biopirol 7M® and Dipel DF®) and the phosphorous compounds used in grapevine (triclorfon and
fenitrotion) were evaluated on adults of the egg parasitoid Trichogramma pretiosum following
IOBC methodology. The experiments were conducted exposing adults (more sensible period) of T. pretiosum to dry pesticide residues sprayed on glass plates. It was observed that Natuneem®
(500 mL/100L), Biopirol 7 M® (500 mL/100L) and Dipel DF® (100g/100L) had been innocuous
(<30% parasitism reduction) while natural piretro (250 mL/100L) was classified as moderad
harmful (80-99% of parasitism reduction). Natural piretro in the higher dose (500 mL/100L)
showed a parasitism deduction in more than 99%equivalent to fenthiom (Lebaycid 500, 100. / Avaliação de inseticidas para o controle de Argyrotaenia sphaleropa (Meyrick, 1909) na
cultura da videira (Lepidoptera: Tortricidae) e efeito secundário sobre Trichogramma
pretiosum (Riley, 1879) (Hymenoptera:Trichogrammatidae). Orientador: Dr. Marcos Botton.
Co-orientador: Dr. Anderson Dionei Grützmacher.
A lagarta-das-fruteiras Argyrotaenia sphaleropa (Meyrick, 1909)(Lepidoptera:Tortricidae) é uma
espécie freqüentemente encontrada danificando a cultura da videira e outras frutíferas temperadas
na região da Encosta Superior do Nordeste do Rio Grande do Sul. Neste trabalho, foi estudado a
variação sazonal de machos adultos de A. sphaleropa na cultura da videira com emprego do
feromônio sexual sintético, o efeito de formulações comerciais de inseticidas com ênfase para os
permitidos na produção orgânica (nim, piretro natural, extrato pirolenhoso e Bacillus
thuringiensis) para o controle do inseto e seu efeito sobre o parasitóide de ovos Trichogramma
pretiosum. Com base na avaliação semanal de machos de A. sphaleropa capturados em armadilha
Delta contendo o feromônio sexual sintético (formulação Z11,13-14Ac + Z11,13-14Al + Z11-
14Al na proporção 4:4:1, impregnada em liberadores de borracha na dose de 1000μg/septo)
durante a safra 2003/2004 foram observados quatro picos populacionais na cultura da videira
cultivar Cabernet Sauvignon. O primeiro pico populacional ocorreu no início do mês de outubro,
o segundo no início de fevereiro e o terceiro teve o acme em meados do mês de março sendo
quarto no mês de junho. Em experimentos conduzidos em laboratório com discos de folhas de
videira com lagartas de 3-4 ínstar e em pomar comercial de videira, observou-se que os inseticidas
Bacillus thuringiensis var. kurstaki (Dipel DF 50, 75 e 100 g/100L) fenitrothion (SumithionÒ 500
CE, 150 mL/100L), e triclorfon (DipterexÒ 500, 300 mL/100L) foram eficientes no controle de A.
sphaleropa, reduzindo a população em níveis superiores a 90%. Em laboratório, os inseticidas
Natuneem® (1500 ppm de Azadiracta indica por litro) e o extrato pirolenhoso (Biopirol 7 M®)
nas doses (250 e 500 mL/100L) não foram eficientes no controle de A. sphaleropa quando
aplicados sobre folhas de videira enquanto que o piretro natural (250 e 500 mL/100L) resultou
em mortalidade significativa, controlando o inseto em 77,65 e 85,88% respectivamente, 120 horas
após a aplicação. O Natuneem® nas concentrações testadas (0,25 e 0,50%) incorporados à dieta
artificial de A. sphaleropa provoca um aumento na duração da fase de lagarta, menor viabilidade
das fases de lagarta e pupa e menor longevidade de machos enquanto que o Biopirol 7M® na
concentração de 0,50% provoca aumento na duração da fase de lagarta, reduz a longevidade de
machos e o período de oviposição sem afetar a fecundidade. Com base na tabela de vida de
fertilidade verificou-se que a presença do Natuneem® e do Biopirol® dietas artificiais nas
concentrações de 0,25% e 0,50% aumentaram a duração em dias de uma geração, a taxa líquida
xiii
de reprodução, a razão infinitesimal de aumento populacional e a razão finita de aumento de A.
sphaleropa quando comparado com a dieta sem os inseticidas. O efeito secundário dos inseticidas
(Natuneem®, piretro natural, Biopirol 7M® e Dipel DF®) e do organo-fosforado fenthiom foi
avaliado sobre adultos do parasitóide de ovos Trichogramma pretiosum seguindo a metodologia
da IOBC. Os testes foram conduzidos expondo-se os adultos (estágio mais sensível) de T.
pretiosum a resíduos secos de pesticidas pulverizados sobre placas de vidro. Foi observado que o
Natuneem® (500 mL/100L), Biopirol 7 M® (500 mL/100L) e Dipel DF® (100g/100L) foram
inócuos (<30% de redução no parasitismo) enquanto o piretro natural na dose de 250 mL/100L
foi classificado como moderamente nocivo (80-99% de redução no parasitismo) e nocivo (>99%
de redução no parasitismo) na dose de 500 mL/100L equivalendo-se ao organo-fosforados.
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Résistance aux insecticides et transmission de la malaria chez le moustique Culex pipiens / Insecticide resistance and malaria transmission by Culex pipiens mosquitoesVézilier, Julien 21 June 2011 (has links)
L'évolution de la résistance aux insecticides chez les moustiques responsables de la transmission de maladies infectieuses compromet notre capacité à contrôler ces populations de vecteurs et pose de graves problèmes de santé publique. Mais les nombreuses modifications physiologiques associées au phénomène de résistance aux insecticides pourraient altérer l'épidémiologie de ces maladies de manière plus indirecte en modifiant la capacité vectorielle des moustiques. Afin d'étudier cette question nous avons mis en place un nouveau système expérimental composé du parasite aviaire Plasmodium relictum SGS1 et de son vecteur naturel le moustique Culex pipiens. Nous avons étudié l'effet de différents allèles de résistance aux insecticides (représentant deux mécanismes principaux i.e. la résistance métabolique ou la modification de la cible) sur une série de traits d'histoire de vie du parasite et du moustique. L'impact de ces différents allèles a été étudié d'une part, dans les conditions contrôlées de leur expression dans un même fond génétique (en utilisant plusieurs souches de moustiques isogéniques), et d'autre part, dans les conditions plus réalistes de leur expression dans un fond génétique hétérogène (utilisation de moustiques échantillonnés sur le terrain). Nous montrons que la résistance aux insecticides a des effets pleïotropes sur l'immunocompétence et les traits d'histoire de vie des moustiques. Son effet sur le développement de Plasmodium semble en revanche limité. Nous discutons d'une part, de la nécessité de poursuivre une approche multifactorielle (impliquant la physiologie, l'immunité et le comportement des moustiques) afin de mieux comprendre l'impact de la résistance aux insecticides sur la transmission de Plasmodium, et d'autre part des perspectives intéressantes qu'offrent ce nouveau système expérimental pour l'étude de l'écologie évolutive des maladies à vecteurs. / The evolution of insecticide resistance in mosquitoes threatens our ability to control many-vector-transmitted diseases, thereby raising serious public health issues. Insecticide resistance entails numerous physiological changes in mosquitoes. This thesis investigates whether these physiological changes alter the quality of mosquitoes as vectors of malaria. To address this issue, we developed a new experimental system consisting in the avian malaria parasite Plasmodium relictum SGS1 and its natural vector, the mosquito Culex pipiens. We investigated the impact of two insecticide resistance mechanisms (target site resistance and metabolic resistance) on several mosquito and parasite life history traits relevant for malaria transmission. The effect of different insecticide resistant genes was investigated using both isogenic laboratory mosquito strains (i.e. against a homogeneous genetic background) and sympatric field caught mosquitoes (i.e. under the more realistic, albeit noisier, conditions of a heterogeneous genetic background). We show that insecticide resistance has a pleiotropic effect on several mosquito traits (immunocompetence, longevity, fecundity), whereas it has only a limited effect on Plasmodium development. We discuss, on the one hand, the need to pursue such a multi-factorial approach (combining the mosquito physiology, immunity and behavior) to better understand the impact of insecticide resistance on malaria transmission and, on the other hand, the promising perspectives offered by this new experimental system for studying the evolutionary-ecology of infectious diseases.
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CONTROLE DE Spodoptera frugiperda (LEPIDOPTERA:NOCTUIDAE) (J.E.SMITH,1917) COM O EXTRATO ETANÓLICO DE Asclepias curassavica L. / Control of Spodoptera frugiperda(LEPIDOPTERA: NOCTUIDAE) (J.E.SMITH, 1917) BY THE ETHANOLIC EXTRACT OF Asclepias curassavica L.Leão, Renato Marcos de 20 February 2018 (has links)
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Previous issue date: 2018-02-20 / The A. curassavica plant is characterized as a toxic plant for vertebrates, and little is known about its effect on invertebrates, such as insects. Thus, a study was conducted to verify the action of A. curassavica on S. frugiperda. The plants were collected, dried and ground, and the raw ethanolic extract was made from the powder. This was added to the diet offered to caterpillars in two trials, one at concentrations of 1%, 2% and 4%; and another at concentrations of 0.05%, 0.1% and 0.5%. The parameters evaluated were: mortality; food consumption; weight of larvae and pupae; fertility (number of eggs and% of hatching). Two trials (one with second instar caterpillars and one with fifth instar caterpillars) of topical applications of the extract at concentrations of 1%, 2%, 4% and 6% were conducted to verify contact action through mortality after treatment. The experiments were performed with and without a choice, using corn leaf disks immersed in ethanolic extract at concentrations of 1%, 2% and 4%, where food intake (g) and preference index were evaluated. A trial was conducted evaluating total polyphenols and flavonoids in extract A. curassavica in order to verify the presence and measure them. The extract of A. curassavica added to the artificial diet, caused mortality of S. frugiperda in all concentrations, with 1%, 2% and 4% showing 100% mortality, and also 0.5% with 98% mortality. The prolongation of the larval period was evidenced in the treatments 0.1% and 0.5%, in 1.29 and 10.75 days respectively, in relation to the control. There was a reduction of larval weight in treatments 0.05%, 0.5%, 1%, 2% and 4% in 15%, 77%, 17%, 97% and 100%, respectively. On the pupal weight, the weight of the pupae in the treatments was 0.05%, 0.1% and 0.5% in 10%, 22% and 54% respectively; already in the weight of the female pupae, there was reduction with the treatment 0.1% in 9.5%. Food consumption was reduced in treatments 0.5%, 1%, 2% and 4% in 22%, 40%, 47% and 57%, respectively. The excreted faeces weight in the treatments 0.1%, 1%, 2% and 4% was 0.730g, 0.002g, 0g and 0g, respectively. At no concentration interference was observed in the number of postures, number of eggs and percentage of hatching. On topical application in the second instar caterpillars, contact action was verified in all concentrations, standing out the 6% treatment that caused 100% mortality after 72 hours of application. However, in the trial with fifth instar caterpillars, there was no contact action in the treatments used. In the tests with and without chance of choice, there was difference in food consumption in all concentrations, especially the reduction in treatment 4%. All treatments were classified as phagdeterrents, and the 4% treatment was less preferred. It was verified the presence of total polyphenois and flavonoids in the extract, presenting 58.75 ug / ml and 150.1 ug / ml, respectively. The extract of A. curassavica should be tested in the field at the concentration of 0.5%, because in this concentration causes high mortality (98%) with the lowest amount of input. / A planta A. curassavica é caracterizada como planta tóxica para vertebrados, e pouco se sabe sobre seu efeito em invertebrados, como insetos. Dessa forma, foi conduzido um estudo para verificar a ação de A. curassavica sobre S. frugiperda. As plantas foram coletadas, secas e moídas, e a partir do pó foi confeccionado o extrato etanólico bruto. Este foi adicionado à dieta oferecida as lagartas, em dois ensaios, um nas concentrações de 1%, 2% e 4%; e outro nas concentrações de 0,05%, 0,1% e 0,5%. Os parâmetros avaliados foram: mortalidade; consumo alimentar; peso de larvas e pupas; fertilidade (nº de ovos e % de eclosão). Dois ensaios (um com lagartas de segundo instar e outro com lagartas de quinto instar) de aplicações tópicas do extrato nas concentrações de 1%, 2%, 4% e 6%, foram conduzidos para verificar a ação de contato através da mortalidade após o tratamento. Foram realizados testes com e sem chance de escolha, utilizando discos foliares de milho imersos sob extrato etanólico nas concentrações de 1%, 2% e 4%, onde avaliaram-se: consumo alimentar (g) e índice de preferência. Foi conduzido ensaio avaliando polifenóis totais e flavonoides no extrato A. curassavica a fim verificar a presença e mensurá-los. O extrato de A. curassavica adicionado a dieta artificial, provocou mortalidade de S. frugiperda em todas concentrações, destacando-se 1%, 2% e 4% apresentaram 100% de mortalidade, e também 0,5% com 98% de mortalidade. O prolongamento do período larval foi evidenciado nos tratamentos 0,1% e 0,5%, em 1,29 e 10,75 dias respectivamente, em relação a testemunha. Houve redução do peso larval nos tratamentos 0,05%, 0,5%, 1%, 2% e 4% em 15%, 77%, 17%, 97% e 100%, respectivamente. Sobre o peso pupal, houve redução do peso das pupas machos nos tratamentos 0,05%, 0,1% e 0,5% em 10%, 22% e 54% respectivamente; já no peso das pupas femêas, houve redução com o tratamento 0,1% em 9,5%. O consumo alimentar foi reduzido nos tratamentos 0,5%, 1%, 2% e 4% em 22%, 40%, 47% e 57%, respetivamente. O peso das fezes excretadas nos tratamentos 0,1%, 1%, 2% e 4% foi de 0,730g, 0,002g, 0g e 0g, respectivamente. Em nenhuma concentração foi verificada interferência no número de posturas, número de ovos e porcentagem de eclosão. Sobre aplicação tópica nas lagartas de segundo instar, foi verificada ação de contato em todas concentrações, destacando-se o tratamento 6% que provocou 100% de mortalidade após 72 horas da aplicação. Porém, no ensaio com lagartas de quinto instar, não se verificou a ação de contato nos tratamentos utilizados. Nos testes com e sem chance de escolha, houve diferença no consumo alimentar em todas concentrações, destacando-se a redução no tratamento 4%. Todos tratamentos foram classificados como fagodeterrentes, e o tratamento 4% obteve a menor preferência. Foi verificada a presença de pólifenois totais e flavonoides no extrato, apresentando 58,75 ug/ml e 150,1 ug/ml, respectivamente. O extrato de A. curassavica deverá ser experimentado a campo na concentração de 0,5%, pois nessa concentração causa alta mortalidade (98%) com a menor quantidade de insumo.
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Seletividade de inseticidas utilizados na cultura dos citros ao predador Ceraeochrysa cubana (Hagen, 1861) (Neuroptera: Chrysopidae), desenvolvimento em diferentes temperaturas e diversidade de crisopídeos em propriedades com manejo intensivo e convencional de Diaphorina citri Kuwayama (Hemiptera: Liviidae) / Selectivity of insecticides used in citrus groves to the predator Ceraeochrysa cubana (Hagen, 1861) (Neuroptera: Chrysopidae), development in different temperatures and lacewing collections in orchards under intensive and conventional management systems of Diaphorina citri Kuwayama (Hemiptera: Liviidae)Rugno, Gabriel Rodrigo 09 April 2013 (has links)
O crisopídeo Ceraeochrysa cubana (Hagen, 1861) é um importante predador na cultura dos citros. Apesar da grande importância de C. cubana, pouco se conhece sobre a biologia e o efeito dos inseticidas a este crisopídeo, o que seria fundamental para um programa de Manejo Integrado de Pragas. Com essa pesquisa objetivou-se avaliar o efeito: a) letal e subletal de inseticidas aplicados sobre ovos com 3 idades diferentes; b) letal e subletal de inseticidas sobre larvas de primeiro instar; c) letal e subletal de inseticidas aplicados sobre pupas e adultos; d) do manejo de Diaphorina citri Kuwayama (Hemiptera: Liviidae) na população de crisopídeos; e) de seis temperaturas sobre a biologia de C. cubana. Verificou-se que não houve diferença significativa das variáveis avaliadas entre os tratamentos, dentre os ovos com 24, 72 e 120 horas. O produto Lorsban® 480 BR afetou a viabilidade dos ovos das três idades e foi o inseticida que mais afetou o predador quando aplicado sobre os ovos, classificado como moderadamente nocivo (classe 3). Em larvas, os inseticidas Lorsban® 480 BR e Malathion® 1000 EC tiveram efeito letal, causando 100% de mortalidade 24h após a aplicação e os inseticidas Azamax® e Engeo Pleno® foram os únicos produtos que tiveram efeito subletal sobre as pupas oriundas das larvas tratadas e nenhum dos produtos testados foram classificados como inócuos (classe 1) ao predador. Nenhum dos inseticidas testados teve efeito letal e subletal quando aplicados sobre as pupas, sendo classificados como inócuos, já, quando aplicados sobre adultos, os inseticidas Actara® 250 WG, Ampligo®, Engeo Pleno®, Lorsban® 480 BR e Malathion® 1000 EC causaram 100% de mortalidade e todos os produtos testados sobre os adultos foram nocivos, exceto Evidence® 700 WG, Imidan® 500 WP e Tiger® 100 EC, que foram classificados como moderadamente nocivos. Nas coletas de crisopídeos feitas em campo, a espécie Ceraeochrysa cincta (SCHNEIDER, 1851) foi a mais coletada, observou-se também que na propriedade com manejo menos intensivo de D. citri foi coletado um número maior de indivíduos comparado com a propriedade com manejo rigoroso. Em relação à biologia, verificou-se um aumento na velocidade do desenvolvimento das fases do predador em função da temperatura e a viabilidade da fase de ovo e larva não foi afetada, porém, a temperatura de 18°C afetou a viabilidade da pupa e no ciclo ovoadulto, além dessa temperatura, a de 32°C também afetou a viabilidade. Para o ciclo total de C. cubana foram necessários 354,61 GD e a temperatura base (Tb) foi de 12,72°C. / The lacewing Ceraeochrysa cubana (Hagen, 1861) is an important predator of citrus pests. Still, little is known about the biology and the effect of insecticides on this green lacewing, which is essential for an Integrated Pest Management program. The aim of this study was to evaluate: a) lethal and sublethal effects of insecticides applied on eggs at 3 different ages, b) lethal and sublethal effects of insecticides on the first larval instar c) lethal and sublethal effects of insecticides applied to pupae and adults; d) effects of the management of Diaphorina citri Kuwayama (Hemiptera: Liviidae) in a lacewing population e) effects of six temperatures on the C. cubana biology. We found no significant differences for the variables in the treatments for eggs at 24, 72 and 120 hours. The insecticide Lorsban® 480 BR affected the viability of the eggs at the three ages and most affected the predator when applied on the eggs, classified as moderately harmful (class 3). On the larvae, the insecticides Lorsban® 480 BR and Malathion® 1000 EC had lethal effect, occurring 100% mortality of the larvae 24h after application of insecticides, and Azamax® and Engeo Pleno® were the only products that presented sublethal effects on pupae from treated larvae and none of the products tested were classified as harmless (class 1) to the predator. None of the insecticides tested had lethal and sublethal effect when applied on the pupae, and were classified as harmless. When applied to adults, insecticides Actara® 250 WG, Ampligo®, Engeo Pleno®, Lorsban® 480 BR and Malathion® 1000 EC caused 100% of mortality of the adult predator and all products tested on adults were harmful, except for Evidence® 700 WG, Imidan® 500 WP and Tiger® 100 EC, which were classified as moderately harmful. In the collections of green lacewings in the field, the species Ceraeochrysa cincta was predominant. We also observed that in orchards under less intensive management of D. citri, a larger number of individuals were collected compared to the orchards under a strict management system. Regarding biology, we observed an increase in growth speed in instars of the predator due to temperature, but the viability of eggs and larvae were not affected. However, the temperature of 18°C affected the pupae viability and the eggadult cycle. The temperature of 32°C also affected viability. For total cycle of C. cubana took 354.61 degrees day (DD) and thermal threshold (Tb) was 12.72°C.
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Effets des toxines insecticides du Bacille de Thuringe sur la perméabilité des vésicules de membrane à bordure en brosse intestinale du sphinx du tabacKirouac, Martin January 2006 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
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Evaluation of Management Strategies for the Headworm Complex in Grain SorghumDobbins, Christopher Scott 07 May 2016 (has links)
During 2013 and 2014, studies were conducted to determine the effects of Helicoverpa zea and Spodoptera frugiperda on both damage and yield of Sorghum bicolor. Results from damage ratings suggest that the amount of damage per single larva decreases as population density increases. Also, yield results suggest that one H. zea and one S. frugiperda larva per panicle results in a 3.6 and 4 percent yield loss, respectively. Additionally, a dynamic EIL was determined using crop value along with various yield potentials and control costs. Other research studies were conducted to determine the efficacy of diamide and pyrethroid insecticides on headworms when applied at midge timing for different locations and planting dates. Results suggest that diamides provide longer and better control of headworms than do pyrethroids. However, applying diamides as a preventative application at midge timing may not be economically feasible when grain prices are low.
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The impact of the variable flow rate application system on pesticide dose-transfer processes and development of resistance to insecticides in fall armyworm Spodoptera frugiperda (J. E Smith)Al-Sarar, Ali Saeed January 2003 (has links)
No description available.
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Evaluation of current agricultural practices and organophosphorus insecticide use in relation to ring-necked pheasant numbers at Klamath Basin Refuges, CaliforniaGrove, Robert Allan 28 February 1995 (has links)
A declining population of ring-necked pheasants (Phasianus colchicus) was
studied at Tule Lake National Wildlife Refuge (TLNWR) from the summer of 1990
through the spring of 1993. Pheasant densities/50 ha at TLNWR in 1989, 1991, and
1992 were considerably lower (16.86, 8.49, and 6.81) than the >62 density seen in
the mid-1950s. Mean body weight of hen pheasants at TLNWR was significantly
lower than hens at nearby Lower Klamath National Wildlife Refuge (LKNWR) which
was not intensively farmed. Mean tarsal lengths of hens at TLNWR were also
significantly shorter than hens at LKNWR, suggesting reduced skeletal growth and
potential nutritional problems. The lack of adequate cover was responsible for poor
early nest success at TLNWR. Later in the season, spring planted crops provided
adequate cover to conceal nesting hens; however, only 0.21 young in 1991 and
0.02 young in 1992 were produced per radio-equipped hen. These rates are
extremely low compared to rates required to maintain a stable population. Most
adult mortality occurred during the spring and early summer months at TLNWR
before crops provided adequate cover, and long before pesticide applications. The
main predator of the pheasants was the golden eagle (Aquila chrvsaetos). Of special
concern at TLNWR was pheasant and other wildlife exposure to anticholinesterase
(antiChE) insecticides used on agricultural croplands at the refuge. Direct toxicity of
antiChE compounds (in this case methamidophos) killed 2 young pheasants, but no
adult radio-equipped hens died as a direct result of insecticide intoxication. This
finding was of particular interest because 15% of the adult pheasants collected in
and around potato fields had 55% brain ChE inhibition. The extent of the effects of
insecticide exposure on the survivorship of pheasant young was uncertain as they
were not radio-equipped. The overriding factor impacting the pheasant population at
TLNWR and to a lesser extent LKNWR was poor habitat, especially in the spring
when most mortality occurred. The poor habitat also resulted in extremely low
recruitment (up to 1 September). Nearly all adult mortality and most of the low
recruitment occurred before the insecticide spray season. The population was nearly
extirpated during the severe winter of 1992-93. / Graduation date: 1995
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