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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Biotechnologies in the Philippines: The Cost of Regulation

Bayer, Jessica Christine 27 June 2007 (has links)
Biotechnologies potentially have significant benefits for developing countries but many countries lack complete regulatory processes to allow their release. In evaluating the potential benefits of genetically modified crops, one must be able to measure the true cost of regulations in addition to the other costs associated with bringing the crop to market. The objectives of this paper are to (1) identify the direct costs of the regulation of Bt eggplant, Bt rice, ringspot virus resistant (PRSV) papaya and virus resistant tomatoes in the Philippines, and (2) estimate the opportunity cost of time lost in the regulatory process. The study compares the cost of regulations as they differ by factors such as the existence of previous studies on the product or the intention for export or domestic use. It is hypothesized that the costs are greater for products that are intended for export or human consumption or are produced by the private sector. It is also hypothesized that these factors increase the time to complete the regulatory process, therefore increasing the opportunity cost of time. This study evaluates the economic impact of the GMO regulatory process on the change in producer surplus, the net present value and the internal rate return using an economic surplus model. Scientists and other experts in the field of GMOs and regulation were interviewed to obtain the necessary data on the regulatory process. The evaluation was carried out for four different commodities in the Philippines, Bt Rice, Bt Eggplant, PRSV Papaya and MVR Tomato. The results for the open economy model revealed a change in producer surplus, as a result of the GMO research, of $418.3 million for Bt Rice and $353.7 million for PRSV Papaya. The closed economy model of Bt Eggplant has a change in producer surplus of $25.1 million and a change in total surplus of $40.8 million while the result for the change in producer surplus for MVR Tomato is $19.3 million and the change in total surplus is $51.6 million. A sensitivity analysis of the results was then carried out in which the elasticity of supply, the cost of regulation, and the release date were each varied in order to show the welfare impact of such changes. The sensitivity analysis revealed limited changes in surplus when elasticity and regulatory costs were changed. However, changing the date of release or commercialization resulted in monumental changes in surplus. / Master of Science
132

Food webs and phenology models: evaluating the efficacy of ecologically based insect pest management in different agroecosystems

Philips, Christopher Robin 02 September 2013 (has links)
Integrated pest management (IPM) is defined as an effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices. Integrated pest management programs use current, comprehensive information on the life cycles of pests and their interactions with host plants and the environment. This information, in combination with available pest control methods, is used to manage pest populations by the most economical means, and with the least possible hazard to people, property, and the environment. True IPM takes advantage of all appropriate pest management options including, as appropriate, the judicious use of pesticides. It is currently estimated the IPM in its full capacity is being practiced on less than ten percent of the agricultural land in the U.S. The primary objective of this research was to evaluate land management decisions and create new tools to promote a true IPM approach and encourage growers to reevaluate their method of insect control. To accomplish this I developed new predictive tools to reduce or eliminate unnecessary insecticide application intended to target cereal leaf beetle in wheat, and assessed a conservation biological control technique, farmscaping, to determine its true impact on lepidopteran pest suppression in collards. / Ph. D.
133

Effects of entomopathogenic fungi used as plant inoculants on plant growth and pest control / Efeitos da utilização de fungos entomopatogênicos como inoculantes no crescimento de plantas e controle de pragas

Canassa, Fernanda 29 April 2019 (has links)
Entomopathogenic fungi (EPF) of the genera Metarhizium and Beauveria are able to endophytically colonize a wide variety of plant species, providing protection against arthropod pests; besides increasing the plant development; and act as phytopathogen antagonists. The main objective of the present project was to evaluate the potential of entomopathogenic fungi as plant inoculants against the two-spotted spider mite Tetranychus urticae and the effects on plant growth promotion. Tritrophic effects were also studied, by evaluating prey consumption and feeding behavior of the predatory mite Phytoseiulus persimilis. The evaluated strategy has several potential benefits compared to the sole use of EPF as contact biocontrol agents, as it may control both pests and phytopathogens; be compatible with other natural enemies; provide limited exposure of fungal propagules to adverse environmental conditions, and accelerate seed emergence and plant growth. Considering this, the effects of seed inoculation using two isolates of Metarhizium robertsii and Beauveria bassiana were evaluated at University of Copenhagen, Denmark, on plant development (i.e. biomass and yield) and T. urticae population growth in a model system with bean plants under greenhouse conditions. Effects on feeding performance of P. persimilis were also studied in laboratory conditions. In Brazil, inoculation studies with EPF were conducted at ESALQ/USP with strawberry plants in greenhouse conditions and in the field in four commercial production areas of strawberries in Atibaia-SP and Senador Amaral-MG. In greenhouse studies, the effects of 15 isolates of Metarhizium spp., 5 isolates of B. bassiana and 5 of Cordyceps (= Isaria) fumosorosea were studied, whereas in the commercial area one isolate of Metarhizium and Beauveria was used. Strawberry roots were inoculated by submersion in fungal suspensions, and the population growth of spider mites, while plants development was assessed by measuring root lengths, biomass of roots and leaves, and the strawberry fruit weight. The results showed a significant reduction in T. urticae population and in general better plant development in both crops. The production of string beans and strawberry fruits were higher in inoculated plants than in non-inoculated plants. There was no difference in predation rate and feeding behavior of the predator mite P. persimilis towards T. urticae from fungal inoculated and uninoculated plants. In the commercial strawberry production areas there were significantly lower populations of T. urticae and fewer symptoms of plant diseases on plants in the fungal treated beds compared to plants in untreated beds. The results of this project bring a new perspective on the use of Metarhizium and Beauveria as plant protecting agents revealing that the use of entomopathogenic fungi as plant inoculants may be a promising strategy. / Fungos entomopatogênicos dos gêneros Metarhizium e Beauveria são capazes de colonizar endofiticamente uma ampla variedade de espécies de plantas e conferir à estas, proteção contra artrópodes pragas; além de acelerar o seu desenvolvimento; e atuar como antagonistas de fitopatógenos. O objetivo geral deste projeto foi avaliar o potencial de fungos entomopatogênicos como inoculantes contra o ácaro rajado Tetranychus urticae e seus efeitos na promoção de crescimento de plantas. O efeito tri-trófico no consumo e comportamento alimentar do ácaro predador Phytoseiulus persimilis também foi estudado. A estratégia avaliada traz vários potenciais benefícios comparado ao uso exclusivo de fungos entomopatogênicos como agentes de controle biológico de contato, como o controle duplo de pragas e fitopatógenos; compatibilidade com outros inimigos naturais; menor exposição de propágulos às condições ambientais adversas, além de acelerar a emergência de sementes e o crescimento de plantas. Diante disso, os efeitos da inoculação de sementes usando dois isolados de Metarhizium robertsii e Beauveria bassiana foram avaliados na Universidade de Copenhagen, Dinamarca, na promoção de crescimento das plantas (biomassa e produção) e no crescimento populacional de T. urticae em um sistema modelo com plantas de feijão em casa-de-vegetação. Efeitos no comportamento alimentar de P. persimilis foram também estudados em condições de laboratório. No Brasil, estudos foram conduzidos na ESALQ/USP com plantas de morangueiro em casa-de-vegetação e em quatro áreas de produção comercial de morangueiro em Atibaia-SP e Senador Amaral-MG. Nos estudos em casa-de-vegetação, os efeitos de 15 isolados de Metarhizium spp., 5 de B. bassiana e 5 de Cordyceps (= Isaria) fumosorosea foram estudados, enquanto em área comercial um isolado de Metarhizium e Beauveria foram utilizados. Raízes de morangueiro foram inoculadas por imersão em suspensões fúngicas, e foram avaliados o crescimento populacional do ácaro rajado e o desenvolvimento das plantas, quantificando o comprimento de raiz, biomassa de raiz e de parte aérea, e massa de frutos de morango. Os resultados mostraram redução significativa na população de T. urticae e em geral melhor desenvolvimento das plantas nas duas culturas. A produção de vagens em plantas de feijão e de frutos de morango foram superiores nas plantas inoculadas em relação às não inoculadas. Não se observou diferenças na taxa de predação e comportamento alimentar do ácaro predador P. persimilis quando oferecidos T. urticae provenientes de plantas inoculadas e não inoculadas. Em campo foram observadas populações significativamente menores de T. urticae e menos sintomas de doenças nas plantas inoculadas com os fungos, comparado às plantas não inoculadas. Os resultados obtidos por este projeto trazem uma nova perspectiva do uso de Metarhizium e Beauveria como agentes protetores de plantas revelando que a utilização de fungos entomopatogênicos como inoculantes pode ser uma estratégia promissora.
134

Variabilidade genética em populações de Heliothis virescens (Lepidoptera: Noctuidae) no Brasil inferida por marcadores microssatélites / Heliothis virescens (Lepidoptera: Noctuidae) populational genetic variation in Brazil inferred by microsatellite markers

Domingues, Felipe Antonio 16 June 2011 (has links)
Estudos de genética de populações de pragas agrícolas têm destacado a importância de se conhecer a estruturação genética e os padrões de fluxo gênico entre populações para o refinamento de estratégias de Manejo Integrado de Pragas (MIP). A lagarta-da-maçã do algodoeiro, Heliothis virescens (F.), é um inseto praga amplamente distribuído e importante economicamente por causar danos consideráveis à cultura do algodão no Brasil. O controle dessa praga tem sido feito principalmente pelo uso de inseticidas e de plantas geneticamente modificadas (GM) que expressam proteína(s) de Bacillus thuringiensis Berliner e o potencial de evolução da resistência é alto. O conhecimento de quanto as populações de H. virescens são capazes de trocar informação genética entre si é de fundamental importância para a implantação de estratégias de manejo dessa praga. No entanto, pouco se sabe sobre a estrutura genética e os padrões de fluxo gênico em H. virescens em escalas locais e regionais no Brasil. Assim, o objetivo desse trabalho foi avaliar a variabilidade genética em populações de H. virescens utilizando marcadores microssatélites. Foram amostrados indivíduos de H. virescens oriundos de populações coletadas nas safras de 2007/08, 2008/09 e 2009/10 nas principais regiões produtoras de algodão e soja no Brasil. Foram estudados nove locos polimórficos em 12 populações, em um total de 205 indivíduos. O número médio de alelos por loco foi de 14,11. Os valores de heterozigosidade média esperada (HE) e observada (HO) foram de 0,303 e 0,438, respectivamente. O coeficinete de endocruzamento da espécie f foi de 0,294 (IC 95% de 0,178 a 0,406). As estimativas de estruturação genética foram = 0,132 (IC 95% de 0,072 a 0,218) e RST = 0,252. Esses valores indicam uma estruturação genética moderada entre as populações. Estimativas do número de migrantes indicaram um pequeno fluxo gênico, principalmente no sentido Centro- Oeste Nordeste, embora a maioria dos indivíduos dentro das populações seja residente; adicionalmente, foi verificado que o estabelecimento das populações do algodão ocorre a partir de indivíduos migrantes da soja ou descendentes desses indivíduos. Análises de Componentes Principais e de atribuição usando inferência Bayesiana revelaram a formação de dois grupos, porém não foi possível identificar um padrão de agrupamento (por região, safra ou hospedeiro). Desta forma os resultados do presente trabalho sugerem uma estruturação genética incipiente para as populações de H. virescens no Brasil. Desse modo, é importante levar esses resultados em consideração para que o MIP em geral, e especificamente para que as abordagens para retardar a evolução da resistência sejam implementadas de forma efetiva para o manejo de H. virescens no Brasil. / Agricultural pests population genetics studies have emphasized the importance of genetic structure and patterns of gene flow knowledge for Integrated Pest Management (IPM) strategies. The tobacco budworm, Heliothis virescens (F.), is a widespread and economically important insect pest renowned for causing considerable damage in cotton fields in Brazil. This pest has been controlled by the use of insecticides and genetic modified plants (GM) expressing proteins from Bacillus thuringiensis Berliner, and it has already been shown to present a high potential to develop resistance to these control technologies. To a successful application of these strategies it is needed to know the capacity of the pest populations to exchange genetic information among them. However, for H. virescens a scarce amount of information about genetic structure and patterns of gene flow is available at local and regional scales in Brazil. In this way, the main objective of this study was to evaluate the genetic variability of H. virescens based on microsatellite markers. Specimens were sampled during 2007/08, 2008/09 and 2009/10 from the main cotton and soybean producers regions in Brazil. From this, nine polymorphic loci from 12 populations were studied in 205 specimens. The average number of alleles was 14.11. Expected (HE) and observed (HO) heterozygosity were 0.303 and 0.438, respectively. Inbreeding coefficient f was 0.294 (IC 95% 0.178 - 0.406). Genetic structure indices were: = 0.132 (IC 95% 0.072 0.218) and RST = 0.252. These values point to a moderate genetic structure among H. virescens populations. Migrants estimative indicate a low gene flow, mainly in the Center-Western Northern direction, although most individuals are residents within populations; additionally it was suggested that immigrants to cotton populations come from soybean fields. Genetic relationships inferred by Principal Component Analysis and Bayesian assignment tests identified two groups, although no group pattern was recognized, even by geographic region, year of sampling or host plant. These results suggest an incipient genetic structuring for H. virescens populations within Brazil. Thus, such results should be considered for IPM strategies aiming in an efficient control of H. virescens in Brazil.
135

Bases biológicas para utilização de Trichogramma pretiosum Riley, 1879(Hymenoptera: Trichogrammatidae) para controle de Pseudoplusia includens (Walker, 1857) e Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae) em soja / Biological base for using Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae to control Pseudoplusia includens (Walker, 1857) and Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae) in soybean

Bueno, Regiane Cristina Oliveira de Freitas 11 August 2008 (has links)
Com o objetivo de avaliar o potencial de utilização de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) no manejo de Pseudoplusia includens (Walker, 1857) e Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae), foram realizados diferentes bioensaios incluindo seleção de linhagens, avaliação das características biológicas, capacidade de parasitismo, exigências térmicas, determinação do número ideal de parasitóide a ser liberado por ovo da praga, capacidade de dispersão e tempo de permanência no campo do parasitóide e seletividade dos agroquímicos ao parasitóide. Através da seleção de espécies/linhagens de Trichogramma e Trichogrammatoidea verificou-se que T. pretiosum, linhagem coletada em Rio Verde, GO (RV) apresentou melhor desempenho biológico dentre as demais. A duração do período de desenvolvimento de T. pretiosum linhagem RV, criado em ovos de ambas as pragas apresentou relação inversa com o aumento de temperatura. A emergência da referida linhagem em ovos de A. gemmatalis não foi afetada na faixa de temperatura estudada, porém quando criada em ovos de P. includens, a temperatura de 32oC afetou tal parâmetro biológico. O limiar térmico inferior de desenvolvimento de T. pretiosum linhagem RV foi menor em ovos de P. includens (10,6ºC) quando comparado com o de A. gemmatalis (11,6ºC) e conseqüentemente, a constante térmica também variou sendo de 152 GD para P. includens e de 128 GD para A. gemmatalis. O número estimado de gerações de T. pretiosum linhagem RV, por ciclo da soja variou de 21 e 20 gerações para Rio Verde, GO e 22 e 21 gerações Barreiras, BA, em ovos de P. includens e A. gemmatalis, respectivamente. O ritmo de parasitismo de T. pretiosum linhagem RV foi influenciado pelas temperaturas testadas, com concentração do parasitismo nos primeiros dias de vida das fêmeas, exceto na temperatura de 18oC em ovos P. includens e nas temperaturas de 18 e 20oC para A. gemmatalis em que o parasitismo ocorreu durante toda a vida do parasitóide. O parasitismo total foi influenciado pelas temperaturas, com maiores valores entre as temperaturas de 22 a 28oC em ovos de P. includens e entre 25 e 28oC em ovos de A. gemmatalis. Em condições de semi-campo, determinou-se que o maior parasitismo foi obtido com uma proporção de 25,6 parasitóides por ovo da praga para as duas espécies de pragas. A capacidade de dispersão na cultura da soja é de 8,0 m, sendo a área de dispersão de 85,18m2. Assim, há a necessidade de 117 pontos de liberação do parasitóide por hectare para uma distribuição homogênea do parasitóides em toda a área. Após a liberação de T. pretiosum linhagem RV os parasitóides permaneceram na cultura da soja por doze dias, embora o parasitismo seja efetivo até o quarto dia. Os resultados básicos obtidos em ovos de P. includens e A. gemmatalis apontam para a possibilidade de controle conjunto destas duas pragas na cultura da soja, com utilização desse parasitóide de ovos. Os inseticidas, herbicidas e fungicidas utilizados na cultura da soja afetaram diferentemente o parasitismo e a viabilidade de T. pretiosum linhagem RV, sendo classificados desde seletivos até nocivos. / Different bioassays were carried out aiming to evaluate the potential of using Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) to manage Pseudoplusia includens (Walker, 1857) and Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae). Among those bioassays there were the strains selection, biological characteristics and parasitism capacity, thermal requirements, establishment of ideal number of parasitoids to be released per number of pest eggs, parasitoid dispersal capacity, amount of time that the parasitoids remain active in the field after releasing and pesticide selectivity to the parasitoid. Throughtout the species/strains selection of Trichogramma and Trichogrammatoidea it was possible to determine that Trichogramma pretiosum, strain collected in Rio Verde (RV), showed the best biological performance among the tested species/strains. Trichogramma pretiosum RV development time, when it was reared in eggs of both pest species, was inversely related to the increase in temperature. T. pretiosum RV reared in A. gemmatalis eggs had not its emergency (%) modified by temperature changes, however, when it was reared in P. includens eggs, it had a lower emergency (%) at 32oC. The lower temperature threshold (Tb) was lower for T. pretiosum RV in P. includens eggs (10.6oC) when compared to T. pretiosum in A. gemmatalis eggs (11.6oC) and consequently the thermal constant (K) was also different being 152 and 128 GD for P. includens and A. gemmatalis eggs, respectively. The estimated number of generations of T. pretiosum RV in eggs of both species varied along soybean crop season being 21 and 20 generations for Rio Verde, GO and 22 and 21 generations for Barreiras, BA in P. includens and A. gemmatalis eggs, respectively. The parasitism rhythm of T. pretiosum RV was changed by the tested temperatures, concentrating the parasitism during the first days except at 18oC in P. includens eggs and at 18 and 20oC in A. gemmatalis eggs when the parasitism occurred during the whole parasitoid lifespan. The total parasitism was influenced by the temperatures, being higher among 22 and 28oC in P. includens eggs and among 25 and 28oC in A. gemmatalis eggs. The higher parasitism rate is reached at 51.2 and 25.6 female parasitoid per P. includens and A. gemmatalis eggs, respectively, accordingly to what was established at greenhouse trials. T. pretiosum RV dispersing capacity in soybean fields is 8.0 m and its dispersal area is 85.18 m2. Therefore, it is required a minimum of 117 parasitoid releasing points per hectare in order to have a homogeneous parasitoid distribution in the field. After T. pretiosum RV release, parasitoids remained in the soybean crop for 12 days. However, the parasitism was effective up to 4 days. The results from this research for P. includens and A. gemmatalis eggs indicate that the control of both pests might be possible using the T. pretiosum RV. Insecticides, herbicides and fungicides commonly used in soybean fields impacted differently the parasitism of T. pretiosum RV, being classified since harmless (class 1) to harmful (class 4).
136

Voláteis de flores de café com etanol e metanol são sinérgicos para a atração de  Hypothenemus hampei (Ferrari) em cafezais / Coffee flower volatiles with ethanol and methanol are synergistic for the attraction of Hypothenemus hampei (Ferrari) in coffee growing areas

Leite, Mariana Oliveira Garrigós 31 May 2016 (has links)
Neste estudo, foi testada a atratividade de novos semioquímicos a fêmeas da broca-do-café, Hypothenemus hampei (Ferrari), que é a principal praga da cultura do café no mundo. Armadilhas iscadas com Trat. 1, Trat. 2 e Trat. 3 foram testadas em combinação ou não com etanol e metanol \'E:M\' (mistura 1:1) em uma área de cafezal localizada em Inconfidentes-MG, Brasil. O resultado mais importante foi que armadilhas iscadas com Trat. 1 + E:M atraíram significantemente mais adultos da broca-do-café do que os outros tratamentos isolados ou combinados. Por outro lado, armadilhas iscadas com compostos voláteis de frutos de café Trat. 2 + E:M não diferiram de E:M. Já armadilhas iscadas com Trat. 3 + E:M atraíram menos besouros do que E:M. Um número significativo de outras espécies de Scolytinae também foram atraídos por armadilhas iscadas com Trat. 1 + E:M e E:M. Além disso, um número muito baixo de outros insetos de, pelo menos, oito ordens também foram atraídos por estes dois tratamentos. Tomados juntos, estes resultados oferecem evidências convincentes de que Trat. 1 e E:M são sinérgicos para a captura de H. hampei, favorecendo o desenvolvimento de uma nova estratégia para o manejo integrado desta espécie em cafezais. / In this study, it was tested the attractiveness of new semiochemicals to coffee berry borer females, Hypothenemus hampei (Ferrari), that is the most important pest of coffee in the world. Traps baited with Treat. 1, Treat. 2 and Treat. 3 were tested in combination or not with ethanol and methanol \"E:M\" (1:1 mixture) in a coffee growing area located in Inconfidentes, MG, Brazil. The most relevant result is that traps baited with Treat. 1 + E:M attracted significantly more coffee berry borer adults than the other treatments. On the other hand, traps baited with coffee fruits volatile compounds Treat. 2 + E:M were similar to the ones bated with E:M. Yet traps with Treat. 3 + E:M attracted significantly less beetles than traps with E:M. A significant number of other Scolytinae species were also attracted by Treat. 1 + E:M and E:M. Moreover, a very low number of other insects from, at least, eight orders were also attracted by these two treatments. Taken together, these results offer compelling evidences that Treat. 1 and E:M are synergistic for the capture of H. hampei, promoting the development of a new strategy for the integrated management of this species in coffee growers.
137

Évaluation du risque de Trypanosomose Animale au Ghana, et suivi de l’impact de l’intervention d’éradication de la maladie et du vecteur dans la region Ouest du Ghana / EVALUATION OF RISK FACTORS OF ANIMAL TRYPANOSOMOSIS IN GHANA, AND THE MONITORING OF THE IMPACT OF DISEASE AND VECTOR ERADICATION INTERVENTION IN THE UPPER WEST REGION OF GHANA

Adam, Yahaya 05 December 2014 (has links)
Les Trypanosomoses Animales Africaines (TAA) sont une contrainte majeure à la viabilité et à la durabilité des systèmes de production de bétail au Ghana. Sous la tutelle de la Campagne Pan-Africaine d'Eradication des Tsé-tsé et des Trypanosomoses (PATTEC), le Ghana collabore avec le Burkina Faso au sein d'un projet sous régional pour créer une zone libérée de glossines à leur frontière commune. Les objectifs de cette thèse sont de i) déterminer la situation initiale avant intervention en ce qui concerne le vecteur et la prévalence de la maladie dans la zone de lutte, ii) déterminer la structure des populations de glossines et ses conséquences sur la durabilité des efforts de lutte anti-vectorielle, iii) évaluer l'efficacité de la Pulvérisation Séquentielle d'Aérosols insecticides (SAT) pour contrôler les glossines riveraines et iv) évaluer les risques environnementaux associés à cette stratégie de lutte. Les résultats de l'enquête de base conduite dans la région nord-ouest du Ghana (zone d'étude) ont montré une large distribution de Glossina tachinoides alors que Glossina palpalis gambiensis était limitée à la limite sud de la zone d'étude. La prévalence parasitaire moyenne chez les bovins était de 2.5% (IC 95%: 1.06-5.77) et la prévalence sérologique de 19% (IC: 14.03-25.35). La densité apparente par piège et par jour (DAP) des glossines était de 8.7, 1.9 et 1.3 respectivement le long des rivières Volta noire, Kulpawn et Sissili. Une structuration génétique importante des populations de G. tachinoides a été observée entre sites d'étude d'un même bassin versant et entre bassins versants. Une densité locale de 0.48-0.61 glossines/m² a été inférée, ainsi qu'une distance de dispersion d'environ 11m par génération [IC 9 - 17]. Aucun biais de dispersion sexe-spécifique n'a été détecté. La dispersion observée était suffisante pour qu'une zone libérée de G. tachinoides puisse être ré-envahie par les populations mitoyennes des bassins versants adjacents.L'efficacité de la SAT à éliminer les espèces de glossines riveraines dans une section particulièrement difficile (canopée très dense et fortes densités de glossines) et l'efficacité ultérieure, un an après la SAT, d'une stratégie de lutte intégrée, ont également été testées. Les résultats montrent l'échec de l'éradication, attribué à une pénétration insuffisante des aérosols insecticides dans les galeries forestières denses. Toutefois, le taux de réduction global obtenu par la SAT fut important (98%) et la stratégie intégrée parvint à maintenir un niveau important de suppression des glossines. Enfin, une mesure de l'impact environnemental du projet a montré un impact non significatif de la deltaméthrine en aérosols sur les arthropodes aquatiques et terrestres non-ciblés. / African animal trypanosomosis (AAT) is a major constraint to viable and sustainable livestock production systems in Ghana. Under the umbrella of the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC), Ghana is collaborating with Burkina Faso in a sub-regional initiative aiming at creating tsetse-free areas across their common borders. The objective of this thesis was to conduct research to guide project implementation and specifically seeks to i) determine the pre-intervention vector and disease situation of the intervention area, ii) determine tsetse population structuring and the consequences on sustainable tsetse control efforts, iii) evaluate SAT for the control of riverine tsetse species in Ghana and iv) evaluate the environmental risk of the intervention programmes. Results of a baseline survey conducted in the Upper West Region (study area) indicated a wide-spread prevalence of Glossina tachinoides but Glossina palpalis gambiensis was limited to the southern edge of the study area. Average parasitological prevalence in cattle was estimated at 2.5% (95% CI: 1.06–5.77) and serological prevalence measured at 19% (95% CI: 14.03–25.35). The mean Index of Apparent Abundance (IAA) of tsetse was 8.7, 1.9 and 1.3 for samples taken along the Black Volta, Kulpawn and Sissili Rivers, respectively. Investigations of the G. tachinoides populations confirmed significant structuring within and between the three main river-basins of the study area, and indicated a local density of 0.48-0.61 flies/m² and dispersal distance that approximated 11 m per generation [CI 9 - 17]. No significant sex-biased dispersal was detected. However, the observed dispersal was deemed sufficient for a G. tachinoides-cleared area to be reinvaded from neighbouring populations in adjacent river basins. The potential of Sequential Aerosol Technique (SAT) to eliminate riverine tsetse species in a challenging subsection (dense tree canopy and high tsetse densities) and the subsequent efficacy of an integrated strategy, one year after the SAT operations, were also investigated. Results indicated failure to achieve elimination, attributed to insufficient penetration of insecticide aerosols in thick riverine forest galleries. However the overall reduction rate due to SAT was important (98%) and the subsequent integrated strategy maintained high levels of tsetse suppression. Finally an environmental impact assessment revealed no significant impact of deltamethrin aerosols on non-targeted aquatic and terrestrial arthropods.
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Seletividade de agrotóxicos utilizados na cultura do trigo aos predadores Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) e Eriopis connexa (Germar,1824) (Coleoptera: Coccinellidae) em condições de laboratório e semi-campo / Side effects of pesticides used in wheat crop for the predators the Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) and Eriopis connexa (Germar, 1824) (Coleoptera: Coccinellidae) in laboratory and semi-field conditions

Pasini, Rafael Antonio 21 February 2017 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-07-11T16:32:21Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese Rafael Antonio Pasini.pdf: 2553408 bytes, checksum: 6b56b5a30a27d4c38a90cbaee22f20f3 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-07-17T20:26:26Z (GMT) No. of bitstreams: 2 Tese Rafael Antonio Pasini.pdf: 2553408 bytes, checksum: 6b56b5a30a27d4c38a90cbaee22f20f3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-17T20:26:26Z (GMT). No. of bitstreams: 2 Tese Rafael Antonio Pasini.pdf: 2553408 bytes, checksum: 6b56b5a30a27d4c38a90cbaee22f20f3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A cultura do trigo apresenta grande importância na alimentação humana e animal. Para que grandes produtividades sejam obtidas, faz-se necessário o controle de insetos, doenças e plantas daninhas. O controle químico é a principal medida utilizada pelos agricultores para o manejo dessas pragas. No entanto, esses agrotóxicos podem afetar de forma negativa os inimigos naturais presentes nesse cultivo. Chrysoperla externa e Eriopis connexa são dois predadores vorazes encontrados com frequência, predando insetos-praga presentes na cultura do trigo. Para que o controle químico e o controle biológico possam ser associados de forma harmoniosa nas lavouras de trigo é necessário que os produtos químicos utilizados sejam seletivos aos insetos benéficos. Nesse sentido, estudos de seletividade a inimigos naturais podem gerar uma grande quantidade de informações importantes para que a associação desses dois métodos de controle possa ser viabilizada, e com o mínimo impacto ao meio ambiente. Objetivou-se com este trabalho avaliar a seletividade de agrotóxicos utilizados na cultura do trigo aos predadores C. externa e E. connexa, utilizando como base a metodologia da “International Organization for Biological and Integrated Control of Noxious Animals and Plants” (IOBC), através de bioensaios em laboratório sobre larvas, ovos, pupas e adultos, além de testes de pesistência biológica em casa-de-vegetação sobre larvas e adultos. O inseticida diflubenzuron SC foi o único inseticida considerado levemente nocivo as larvas de E. connexa. Os inseticidas inibidores da biossíntese de quitina diflubenzuron SC, diflubenzuron WP, lufenuron e triflumuron apresentaram reduzida mortalidade aos adultos de C. externa e E. connexa. Para os ovos dos predadores, o inseticida etofenproxi foi classificado como levemente nocivo a C. externa, sendo que imidacloprido+beta-ciflutrina, diflubenzuron WP, tiametoxam+lambda-cialotrina A e B, gama-cialotrina e etofenproxi apresentaram a mesma classificação para E. connexa, tendo ainda metomil sendo classificado como moderadamente nocivo aos ovos do predador. Imidacloprido+beta-ciflutrina foi considerado como levemente nocivo as pupas de C. externa enquanto imidacloprido+beta-ciflutrina, tiametoxam+lambda-cialotrina A e B e lufenuron apresentaram efeito total superior a 30% e foram classificados como levemente nocivos as pupas do predador E. connexa. Quanto a persistência, com exceção de tiametoxam+lambda-cialotrina que 7 foi moderadamente persistente, gama-cialotrina, imidacloprido+beta-ciflutrina, metomil e tiametoxam foram persistentes as larvas de C. externa e E. connexa. Gama-cialotrina, imidacloprido+beta-ciflutrina e metomil foram persistentes a C. externa e imidacloprido+beta-ciflutrina e metomil aos adultos de E. connexa. Tiametoxam foi considerado moderadamente persistente a C. externa e gamacialotrina, tiametoxam e tiametoxam+lambda-cialotrina a E. connexa. O inseticida tiametoxam+lambda-cialotrina foi levemente persistente aos adultos de C. externa. O herbicida glufosinato de amônio foi classificado como moderadamente nocivo a fase larval de ambos os predadores. Quase todos os herbicidas foram classificados como inócuos aos ovos dos dois predadores, com exceção de metsulfuron-metil que foi classificado como levemente nocivo aos ovos de E. connexa. O herbicida 2,4-D amina foi classificado como levemente nocivo a pupas de C. externa e pirimidinadiona apresentou a mesma classificação a pupas de E. connexa. Os fungicidas piraclostrobina+epoxiconazole B e picoxistrobina+ciproconazole são nocivos as larvas de C. externa. Piraclostrobina+epoxiconazole A foi levemente nocivo a fase de ovo, e propiconazol foi levemente nocivo a fase de pupa de C. externa. O fungicida piraclostrobina+epoxiconazole A foi considerado nocivo as larvas de E. connexa. Piraclostrobina+epoxiconazole A e tebuconazole A foram levemente nocivos a fase de ovo, e piraclostrobina+epoxiconazole A e propiconazol foram levemente nocivos a fase de pupa do coccinelídeo. / The wheat crop hasp great importance in the human and animal nutrition. In order to obtain large yields, it is necessary the control of insects, diseases and weeds. The chemical control through the use of pesticides is the main measure used by farmers to manage these pests. However, these pesticides can negatively affect the natural enemies present in this crop. Chrysoperla externa and Eriopis connexa are two very voracious predators and are found often preying on aphids present in wheat crop. In order for chemical control and biological control to be harmoniously associated in the wheat crop, it is necessary that the chemicals used must be selective for beneficial insects. So, studies of selectivity to natural enemies can generate a large amount of important data for the association of these two control methods can be made feasible, with minimal impact to the environment. The objective of this work was to evaluate the selectivity of agrochemicals used in the wheat crop to the predators C. externa and E. connexa, based on the methodology of the International Organization for Biological and Integrated Control of Noxious Animals and Plants (IOBC) Through laboratory bioassays on larvae, eggs, pupae and adults, in addition to tests of biological persistence in greenhouse conditions on larvae and adults. The insecticide diflubenzuron SC was the only insecticide considered to be slightly harmful to E. connexa larvae. The chitin biosynthesis inhibitors diflubenzuron SC, diflubenzuron WP, lufenuron and triflumuron showed reduced mortality on adults of C. externa and E. connexa. For the eggs of the predators, the insecticide etofenproxi was classified as slightly harmful to C. externa, and imidacloprid+beta-cyfluthrin, diflubenzuron WP, thiamethoxam+lambda-cyhalothrin A and B, gamma-cyhalothrin and etofenproxi showed the same classification for E. connexa, being methomyl classified as moderately harmful to the predator eggs. Imidacloprid+beta-cyfluthrin was considered as slightly harmful the pupae of C. externa while imidacloprid+betacyfluthrin, thiamethoxam+lambda-cyhalothrin A and B and lufenuron had a total effect superior to 30% and were classified as slightly harmful to the pupae of the predator E. connexa. Regarding the insecticide persistence, with the exception of thiamethoxam+lambda-cyhalothrin that was moderately persistent, gammacyhalothrin, imidacloprid+beta-cyfluthrin, methomyl and thiamethoxam were persistent to C. externa and E. connexa larvae. Gamma-cyhalothrin, 9 imidacloprid+beta-cyfluthrin and methomyl were persistent to C. externa and imidacloprid+beta-cyfluthrin and methomyl to adults of E. connexa. Thiamethoxam was considered moderately persistent to C. externa and gamma-cyhalothrin, thiamethoxam and thiamethoxam+lambda-cyhalothrin to E. connexa. The insecticide thiamethoxam+lambda-cyhalothrin was slightly persistent to C. externa adults. The herbicide ammonium glufosinate was classified as moderately harmful to the larval phase of both predators. Almost all herbicides were classified as innocuous to the eggs of both predators, with the exception of metsulfuron-methyl which was classified as slightly deleterious to E. connexa eggs. The herbicide 2,4-D amine was classified as slightly harmful to pupae of C. externa and pyrimidinedione presented the same classification to E. connexa pupae. The fungicides pyraclostrobin +epoxiconazole B and picoxystrobin+ciproconazole are harmful to C. externa larvae. Piraclostrobin+epoxiconazole A was slightly harmful to the egg phase, and propiconazole was slightly harmful to the pupa phase of C. externa. The fungicide pyraclostrobin+epoxiconazole A was considered to be harmful to E. connexa larvae. Piraclostrobin+epoxiconazole A and tebuconazole A were slightly harmful to the egg phase, and pyraclostrobin+epoxiconazole A and propiconazole were slightly harmful to the pupal phase of the coccinellidae.
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Seletividade de produtos fitossanitários utilizados na cultura do pessegueiro aos predadores Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) e Coleomegilla quadrifasciata (Schöenherr, 1808) (Coleoptera: Coccinellidae) / Side effects of pesticides used in peach crop on predators Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) and Coleomegilla quadrifasciata (Schöenherr, 1808)

Armas, Franciele Silva De 06 March 2017 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-09-22T16:02:25Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Franciele Silva De Armas.pdf: 1223681 bytes, checksum: 9be73b97e5429620ff32bb2796597003 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-09-25T19:45:38Z (GMT) No. of bitstreams: 2 Dissertação Franciele Silva De Armas.pdf: 1223681 bytes, checksum: 9be73b97e5429620ff32bb2796597003 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-25T19:45:38Z (GMT). No. of bitstreams: 2 Dissertação Franciele Silva De Armas.pdf: 1223681 bytes, checksum: 9be73b97e5429620ff32bb2796597003 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-06 / Na cultura do pessegueiro, o controle químico é a estratégia mais utilizada no manejo dos insetos-praga, entretanto, medidas alternativas de controle, como o controle biológico, fundamentadas no Manejo Integrado de Pragas (MIP), devem ser priorizadas. Nesse sentido, estudos de seletividade a inimigos naturais podem gerar informações importantes para que a associação desses métodos de controle possa ser viabilizada. Assim, objetivou-se com este trabalho avaliar a seletividade de nove produtos fitossanitarios utilizados em pomares de pêssego sobre os predadores Chrysoperla externa e Coleomegilla quadrifasciata utilizando a metodologia proposta pela “International Organization for Biological and Integrated Control of Noxious Animals and Plants” (IOBC). Nos bioensaios com ovos e pupas foram realizadas aplicações diretas. Os bioensaios com larvas e adultos consistiram na exposição dos insetos a resíduos secos de produtos fitossanitários pulverizados sobre placas de vidro. Nos bioensaios com ovos e pupas foi avaliado a redução de emêrgencia das larvas e redução na emergência dos adultos, respectivamente, e posterior avaliação da fecundidade e fertilidade nos adultos sobreviventes. Nos bioensaios com larvas foram avaliadas a duração dos estágios de des.envolvimento, a mortalidade, e as taxas de fecundidade e fertilidade dos adultos sobreviventes. Nos bioensaios com adultos, foi avaliada a mortalidade acumulada as 24, 72 e 120 horas após a exposição dos insetos aos resíduos dos produtos fitossanitários. A seletividade foi calculada através do efeito total, para todas as fases, onde os produtos fitossanitários foram classificados em inócuos (<30%), levemente nocivos (30-79%), moderadamente nocivos (80- 99%) e nocivos(>99%), conforme recomendação da IOBC. Conclui-se que para C. externa todos os produtos fitossanitários (Dosagem comercial) mostraramse inócuo (classe 1) para ovos, entretanto, sobre a fase de pupa, abamectina (80) e cobre + cálcio (1%), foram levemente nocivos (classe 2). Para a fase de ovo de C. quadrifasciata fenitrotiona (100) apresentou-se moderamente tóxico (classe 3). Abamectina (80), deltametrina (40) e malationa (150) foram levemente nocivo (classe 2), os demais produtos mostraram-se inócuos (classe 1), já para a fase de pupa os produtos abamectina (80), fenitrotiona (100) e malationa (150) foram tóxicos (classe 4), e os demais produtos foram inócuos (classe 1) a C. quadrifasciata. O coccinilideo C. quadrifasciata foi mais sensível que o crisopideo C. externa a todos os produtos fitossanitários testados nas fases de ovo e pupa. Os produtos Azadiractina (1%), clorantraniliprole (14) e cobre + cálcio (25 %+ 10%) foram inócuos (classe 1) á fase larval de C. externa. Já os produtos abamectina (80) e cobre + cálcio (1%) foram levemente nocivos (classe 2) ao predador nesta fase. Deltametrina (40), fenitrotiona (100) malationa (150) e enxofre + cálcio (3,5º Ba) foram nocivos (classe 4) á larvas deste crisopideo. Já para a fase adulta de C. externa Azadiractina (1%), clorantraniliprole (14) e cobre + cálcio (25 %+ 10%) foram inócuos (classe 1), e abamectina (80) foi levemente nocivo (classe 2). Os produtos deltametrina (40), fenitrotiona (100), malationa (150) e cobre + cálcio (1%) e enxofre + cálcio (3,5° Ba) foram nocivos (classe 4) á adultos de C. externa. Para a fase larval de C. quadrifasciata clorantraniliprole (14) foi inócuo (classe 1). O produto enxofre + cálcio (3,5º Ba) foi levemente nocivo (classe 2), já o produto cobre + cálcio (25% + 10%) foi moderamente nocivo (classe 3), os demais produtos foram nocivos (classe 4). Na fase adulta de C. quadrifasciata os produtos Azadiractina (1%) e cobre + cálcio (25%+ 10%) foram inócuos (classe 1). Clorantraniliprole (14), deltametrina (40) e cobre + cálcio (1%) foram levemente nocivos (classe 2). Abamectina (80), fenitrotiona (100) malationa (150) e enxofre + cálcio (3,5º Ba) foram nocivos (classe 4). / In the peach crop, the chemical control is the most used strategy in the management of pest insects, however, alternative control measures, such as biological control, based on Integrated Pest Management (IPM), must be prioritized. In this sense, side effects studies of natural enemies can generate important information so that an association of control methods can be made feasible. In this sense, the objective of this work was to evaluate the side effects of nine pesticides used in peach orchards on Chrysoperla externa and Coleomegilla quadrifasciata using the methodology proposed by the International Organization for Biological and Integrated Control of Noxious Animals and Plants (IOBC). In the bioassays eggs and pupae were carried out direct applications. Bioassays with larvae and adults consisted of exposure of insects to dry residues of sprayed pesticides on glass slabs. In the bioassays with eggs and pupae, larval emergence reduction and reduction in adult emergence, respectively, and subsequent fertility and fertility evaluation in surviving adults were evaluated. In larval bioassays the duration of developmental stages, mortality, and fertility and fertility rates of surviving adults. In the adult bioassays, the accumulated mortality at 24, 72 and 120 hours after exposure of the insects to the residues of the phytosanitary products was evaluated. The side effects was calculated by the total effect for all phases, where the pesticides were classified as innocuous (<30%), slightly harmful (30- 79%), moderately harmful (80-99%) and harmful (> 99 %), recommended by IOBC. It was concluded that for C. externa all phytosanitary products showed to be innocuous (class 1) for eggs, however, on the pupal phase, abamectin (80) and copper + calcium (1%) were slightly harmful (class 2). For the egg phase of C. quadrifasciata fenitrothione (100) it was moderately toxic (class 3). Abamectin (80), deltamethrin (40) and malathion (150) were slightly harmful (class 2), the other products were innocuous (class 1), and for the pupae phase the products abamectin (80), fenitrothion (100) and malathion (150) were toxic (class 4), and the other products were innocuous (class 1) to C. quadrifasciata. The ladybug C. quadrifasciata was more sensitive than C. externa to all pesticides tested in the egg and pupal phases. The products Azadirachtin (1%), chlorantraniliprole (14) and copper + calcium (25% + 10%) were innocuous (class 1) to the larval phase of C. externa. The abamectin (80) and copper + calcium (1%) products were slightly harmful (class 2) to the predator at this stage. Deltamethrin (40), fenitrothione (100) malathion (150) and sulfur + calcium (3.5 ° Ba) were harmful (class 4) to larvae of this insect. In the adult phase of C. externa the Azadirachtin (1%), chlorantraniliprole (14) and copper + calcium (25% + 10%) were innocuous (class 1), and abamectin (80) was slightly harmful (class 2). The products deltamethrin (40), fenitrothion (100), malathion (150), copper + calcium (1%) and sulfur + calcium (3.5 ° Ba) were harmful (class 4) to C. externa adults. For the larval phase of C. quadrifasciata chlorantraniliprole (14) was innocuous (class 1). The product sulfur + calcium (3.5 ° Ba) was slightly harmful (class 2), while the product copper + calcium (25% + 10%) was moderately harmful (class 3), the other products were harmful (class 4).In the adult phase of C. quadrifasciata the products Azadirachtin (1%) and copper + calcium (25% + 10%) were innocuous (class 1). Chlorantraniliprole (14), deltamethrin (40) and copper + calcium (1%) were slightly harmful (class 2). Abamectin (80), fenitrothione (100) malathione (150) and sulfur + calcium (3.5 ° Ba) were harmful (class 4).
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Potencial inseticida de extratos de funcho, erva-doce, cravo-da-índia e do preparado homeopático para o controle de pulgão em couve / Insecticidal Potential of Fennel, Sweet Herb, Clove Extracts and Homeopathic Preparations to Control Aphid in Cabbage

Lucca, Patricia Stadler Rosa 10 June 2010 (has links)
Made available in DSpace on 2017-07-10T19:24:35Z (GMT). No. of bitstreams: 1 Patricia Stadler Rosa Lucca.pdf: 1596078 bytes, checksum: 26545cacc279bf8104c7bd2edea4d008 (MD5) Previous issue date: 2010-06-10 / The use of natural substances for pest management in agriculture is, economically, a viable option and has benefits for both human-beings and environment, due to its low persistence and toxicity. Thus, this trial aimed at determining the insecticidal potential of extracts and essential oils of fennel (Foeniculum vulgare), sweet herb (Pimpinella anisum), clove (Caryophillus aromaticus) and of homeopathic preparations from CH 05 and CH 06 aphid on the control of Brevicoryne brassicae in cabbage (Brassica oleracea var. acephala). The treatments were: fennel extracts, sweet herb and cloves at 10%; fennel oils, sweet herb and cloves at 1%; homeopathic preparations with CH 05 and CH 06 aphid; control with distilled water. The mortality tests were done concerning nymphs and adults of aphids in laboratory, with three replications, each one consisting of a cabbage leaf kept inside a Petri dish containing moistened cotton. On each plate, ten nymphs were released added with a 1 mL spray of the respective solutions. The plates were covered with a perforated plastic film and incubated with a 12 hour photoperiod at 25 ° C. Evaluations were performed after 1, 12, 24, 48 and 72 hours. After analysis in the laboratory, some tests were done with the culture, in pots, only with the Indian cloves extracts at 10% and fennel oil at 1% treatments, since they were significant. There was, moreover, the sensorial analysis of cabbage, treated with clove extract at 10% and fennel oil at 1%. Data analysis was performed by analysis of variance and averages comparison by Tukey, at 5% of significance. In lab tests, it was found out that fennel oil at 1% showed the best rate of mortality on aphid nymphs, which means 70%, at 72 h, followed by clove extract at 10% with 37% of mortality. It was registered for survival of adults aphids that the fennel oil at 1%, fennel extract at 10% and clove extract at 10% had the lowest survival rates, as: 46%, 53% and 53 %, respectively. A mortality test was carried out in the culture and it was registered the effectiveness of clove extract at 10% and fennel oil at 1%, and they had 6% and 8% of survival in adults aphids, respectively. The sensorial analysis of cabbage did not indicate any significant difference among them, at 5% significance. / O uso de substâncias naturais para manejo de pragas da agricultura é uma opção economicamente viável e traz benefícios tanto ao homem como ao ambiente, devido a sua baixa persistência e toxicidade. Dessa forma, o objetivo do trabalho em questão foi verificar o potencial inseticida de extratos e óleos essenciais de funcho (Foeniculum vulgare), erva doce (Pimpinella anisum), cravo-da-Índia (Caryophillus aromaticus) e dos preparados homeopáticos para o controle de Brevicoryne brassicae em couve (Brassica oleracea var. acephala). Os tratamentos utilizados foram os extratos de funcho, erva-doce e cravo-da-Índia a 10%; óleos de funcho, erva-doce e cravo-daÍndia a 1%; preparados homeopáticos de pulgão CH 05 e CH 06 e controle com água destilada. Realizaram-se testes de mortalidade sobre ninfas e adultos de pulgão em condições de laboratório, com três repetições, cada uma constituída por uma folha de couve mantida no interior de uma placa de Petri contendo algodão umedecido. Em cada placa, foram liberadas dez ninfas e pulverizado 1 mL das respectivas caldas. As placas foram cobertas com filme plástico perfurado e incubadas com fotoperíodo de 12 horas a 25 °C. Avaliações foram realizadas após 1, 12, 24, 48 e 72 h. Após análise em condições de laboratório, realizaram-se testes na cultura, em vasos, somente com os tratamentos extrato de cravo-da-Índia a 10% e óleo de funcho a 1%, pois os mesmos apresentaram-se significativos. Realizou-se, ainda, análise sensorial das couves tratadas com o extrato de cravo a 10% e óleo de funcho a 1%. A análise dos dados ocorreu por análise de variância e comparação de médias por Tukey, a 5% de significância. Nos testes realizados em laboratório, verificou-se que, o óleo de funcho a 1% apresentou a melhor mortalidade sobre as ninfas de pulgão, ou seja, 70%, às 72 h, seguido do extrato de cravo a 10%, com 37% de mortalidade. Quanto à sobrevivência de adultos de pulgão, verificou-se que o óleo de funcho a 1%, extrato de funcho a 10% e o extrato de cravo a 10% apresentaram os menores índices de sobrevivência, ou seja, 46%, 53% e 53%, respectivamente. No teste de mortalidade realizado na cultura, observou-se a efetividade do extrato de cravo a 10% e do óleo de funcho a 1%, em que os mesmos obtiveram 6% e 8% de sobrevivência de adultos de pulgões, respectivamente. A análise sensorial das couves não indicou diferença significativa entre as mesmas, a 5% de significância.

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