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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.
161

Intensidade de sintomas de oídio em minijardim clonal de eucalipto sob diferentes ambientes de cultivo /

Ruiz, Anny Mery Marcon. January 2019 (has links)
Orientador: Edson Luiz Furtado / Coorietador: Cristiane de Pieri / Coorietador: Fábio Suzart Albuquerque / Banca: Gilberto Rostirolla Batista de Souza / Banca: Fernando Broetto / Resumo: Em 2016, a eucaliptocultura atingiu 5,67 milhões de hectares plantados no Brasil, garantindo uma grande rentabilidade ao setor (IBÁ, 2017). Para manter esse patamar, é necessário a produção de mudas no viveiro e realizar o manejo adequado das plantas e doenças. Podosphaera pannosa (Wallr.) de Bary (oídio do eucalipto) é um dos principais patógenos biotróficos encontrados em viveiros florestais, que afeta o processo fotossintético da planta e causa intensos danos. Para o controle desta doença, é necessário encontrar novas alternativas, umas delas pode ser o uso de filmes plásticos difusores, os quais são responsáveis em aumentar a umidade e temperatura, filtrar a radiação fotossinteticamente ativa (PAR), e como consequência melhorar o desenvolvimento das plantas e controlar doenças. Para o sucesso do controle, é necessário compreender o comportamento do patógeno e realizar a quantificação dos sintomas. Dessa maneira, esse trabalho apresenta como objetivos específicos: 1) desenvolver a escala diagramática de oídio do eucalipto; 2) Avaliar o patossistema oídio-eucalipto em quatro materiais genéticos distintos de eucalipto Híbridos de Corymbia torelliana x C. citriodora ("Toreliodora"), Eucalyptus urophylla x E. grandis (IPB 02, IPB 13) e híbrido natural de E. urophylla (I144) em minijardim clonal sob quatro ambientes de cultivo (Pé direito alto, descoberto, mini túnel com plástico difusor branco e mini túnel com plástico difusor azul); 3) Correlacionar a intensidade de oídio com... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In 2016, eucalyptus cultivation reached 5.67 million hectares planted in Brazil, guaranteeing a great profitability to the sector (IBÁ, 2017). To maintain this level, it is necessary to produce seedlings in the nursery and to carry out the appropriate management of the plants and diseases. Podosphaera pannosa (Wallr.) de Bary (Eucalyptus powdery mildew) is one of the main biotrophic pathogens found in forest nurseries, which affects the photosynthetic process of the plant and causes severe damage. To control this disease, it is necessary to find new alternatives, one of them may be the use of diffuser plastic films, which are responsible for increasing the humidity and temperature, filtering the photosynthetically active radiation (PAR), and consequently improving the development of plants and control diseases. For the success control of this disease, it is necessary to understand the behavior of the pathogen and perform the symptom quantification. In this way, this study presents as specific objectives: 1) to develop the diagrammatic scale of eucalyptus powdery mildew; 2) evaluate the oidium-eucalyptus patossystem in four different genetic materials of eucalyptus Hybrids: Corymbia torelliana x C. citriodora ("Toreliodora"), Eucalyptus urophylla x E. grandis (IPB 02, IPB 13) and natural hybrid of E. urophylla (I144) in clonal mini-garden under four different coverings (high right foot, uncovered, mini tunnel with white diffuser plastic and mini tunnel with blue diffuser plastic); 3) Correlate the intensity of powdery mildew with photosynthetically active radiation, temperature, rain and relative humidity; 4) measure the leaf nitrogen content of the clones in the different treatments; 5) analyze the plant defense metabolic responses through the enzymes peroxidase and superoxide dismutase (SOD). The experiment was installed in the Forest Nursery in the Department of Forest Science of the Faculty of ... / Mestre
162

Evaluation study on linkages of selected pieces of legislation and spheres of government on plant health system in South Africa

Rambauli, Maanda 02 1900 (has links)
Plant health system is an important element for the control and management of plant pests to ensure food production and security as well as safe trade. The objectives of this study were to: identify the existing knowledge gaps on current plant health system at the national and provincial level, identify critical areas to be addressed in the current plant health institutional framework and identify the existing limitations and risks on current legislation. A semi-structured questionnaire was used to collect the data. The data was analysed statistically using the one-way frequency and Spearman’s Rank correlation coefficients.The study found that the Provincial Departments of Agriculture (PDAs) (below 50%) lack knowledge of plant health system as compared to the national authorities: DAFF and DEA (above 70%). The study also found that there were no formal linkages between the national and provincial authorities. The study further revealed that there is a need for harmonisation of relevant legislation. It can be concluded that there are knowledge gaps on plant health matters between the national authority and the provincial level and that there are no formal linkages within the spheres of government on plant health matters. / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
163

Modifying an artificial diet for mass rearing mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), using locally available maize meal

Rini, Lulama Angela 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is well-known as a destructive pest of fruit worldwide. Various control methods have been used against this insect. The sterile insect technique (SIT) is used as an important and successful technological method for controlling or eradicating this pest in many countries. A key factor to successfully apply SIT is dependent on the availability of efficient and economical rearing methods. Artificial insect diets with low cost bulking agents have been of interest to many researchers. The present study investigated the use of locally available maize meal as a bulking agent in such diets. Maize meal is used for human consumption (in South Africa) and contains small amounts of protein. This makes the reduction of imported torula yeast as an ingredient of the diet and source of protein possible, thereby reducing the cost of the diet. The larval development of the Medfly reared on artificial diets was studied in small and large-scale tests. The effect of the diets on larval production was evaluated using pupal recovery, pupal weight, flight ability, sex ratio, fecundity and egg fertility. The results of the small-scale tests showed that the diet containing maize meal could be used to produce Medfly more economically than the standard Krige diet used by the ARC Infruitec-Nietvoorbij Research Institute at Stellenbosch. However, in large-scale tests the ingredients quantities of the diets used were not the same as those of small scale-tests. The cost of the modified larval diet was not reduced in large-scale tests. This was ascribed to the number of eggs used in the tests to produce one million of fruit flies. The maize meal with reduced number of eggs require more diet to produce one million flies therefore, making it more expensive and less viable. When similar amounts of eggs were used, the diet appears to be a suitable alternative as the result obtained was almost similar to those of the Krige diet. / AFRIKAANSE OPSOMMING: Die Mediterreens vrugtevlieg ("Medfly"), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is wêreldwyd 'n skadelike plaag. Die steriele insek tegniek (SIT) het in baie lande 'n belangrike en suksesvolle manier geword om die plaag te beheer en uit te roei. Die belangrikste voorvereiste vir die suksesvolle toepassing van SIT is die beskikbaarheid van doeltreffende en ekonomiese teelmetodes. Meeste navorsers is geïntereseerd in kunsmatige diëte met 'n goedkoop vulstof. Hierdie studie is ontwerp om die gebruik van plaaslik beskikbare mieliemeel as vulstof te ondersoek. In Suid-Afrika word dit vir menslike gebruik aangewend en bevat klein hoeveelhede proteïene wat 'n vermindering van die ingevoerde torula gis moontlik kan maak, en sodoende die koste van die dieët kan verminder. Die ontwikkeling van Medfly larwes op kunsmatige diëte is bestudeer In kleinskaalse en grootskaalse eksperimente. Die invloed van die diëte op larwale produksie is evalueer deur gebruik te maak van van papie-ontwikkeling, papie-gewig, vliegvermoë, geslagsverhouding, volwasse voortplantingsvermoë en eiervrugbaarheid. Die resultate van die kleinskaalse toetse het aangetoon dat die mieliemeel dieët gebruik kan word om Medfly meer ekonomies as met die standaard Krige dieët, wat in die ARC Infruitec-Nietvoorbij navorsings instituut by Stellenbosch gebruik word, te teel. By die grootskaalse toetse was die koste nie laer nie. Dit word toegeskryf aan die aantal eiers wat gebruik is om 'n miljoen vlieë te produseer. Die mieliemeel dieët met 'n verminderde aantal eiers benodig meer dieët om 'n miljoen vlieë te produseer, wat dit duurder en minder lewensvatbaar maak. Wanneer soortgelyke hoeveelhede eiers gebruik was, het dit geblyk dat die dieët 'n opsie is, want die resultaat was soortgelyk aan dié van die Krige dieët.
164

Interações moleculares das proteínas CRY1 e VIP3 no controle de lepidópteros em cana-de-açúcar /

Lemes, Ana Rita Nunes. January 2016 (has links)
Orientador: Janete Apparecida Desidério / Resumo: O potencial biotecnológico das proteínas Cry e Vip provenientes da bactéria Bacillus thuringiensis é amplamente conhecido. Porém, a evolução da resistência de pragas é a principal ameaça a longo prazo do controle de insetos-praga por plantas transgênicas com toxinas desta bactéria. Estudos relatam a necessidade de se retardar a evolução da resistência e dentre as possibilidades, a utilização de mais de um gene na construção de plantas transgênicas mostra-se eficiente. Dessa forma, é importante buscar novos genes, com diferentes modos de ação, e selecionar os que apresentam atividade entomotóxica diferenciada para Diatraea flavipennella e Elasmopalpus lignosellus, que são pragas secundárias e potenciais da cana-de-açúcar. Para tanto, proteínas Cry1 e Vip3 foram expressas em Escherichia coli e a toxicidade verificada por meio de bioensaios com lagartas neonatas de ambas as espécies de insetos-praga. As proteínas foram purificadas, solubilizadas, ativadas com tripsina e biotiniladas. As BBMVs (Brush Border Membrane Vesicles) foram preparadas a partir dos intestinos de lagartas das duas espécies para realização de ensaios de competição homóloga e heteróloga. Considerando a CL50, as proteínas Cry1Ac e Vip3Aa foram as mais efetivas no controle dos insetos-praga em estudo. O ensaio de ligação mostrou que ocorreu interação entre todas as proteínas e os receptores das duas espécies de lagartas. Os ensaios de competição heteróloga demonstraram não haver competição entre as proteínas Cr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The biotechnological potential of Cry and Vip proteins from the bacterium Bacillus thuringiensis is widely known. However, the evolution of pest resistance is a major threat to long-term control of insect pests by transgenic plants with toxins of this bacterium. Studies have reported the need to slow down the evolution of resistance and, among the possibilities, the use of more than one gene in the construction of transgenic plants is shown to be efficient. Thus, it is important to look for new genes with different modes of action, and select those with different entomotoxic activity to Diatraea flavipennella and Elasmopalpus lignosellus, which are secondary and potential sugarcane pests. Therefore, Cry1 and Vip3 proteins were expressed in Escherichia coli and the toxicity was verified by bioassays using neonate larvae of both species of the insect pests. The proteins were purified, solubilized, and activated with trypsin and biotinylated. The BBMVs (Brush Border Membrane Vesicles) were prepared using the intestines of the two species to perform the homologous and heterologous competition assays. Considering the LC50, the Cry1Ac and Vip3Aa proteins were the most effective in controlling the insect pests in this study. The binding assays showed that there was interaction between the proteins and the receptors of the two species of larvae. The heterologous competition assays showed no competition between Cry1 and Vip3 proteins for the same binding sites for both species studied... (Complete abstract click electronic access below) / Doutor
165

Efeito de pontas e volumes de pulverização na deposição de calda na cultura do milho e em plantas daninhas /

Terra, Marcelo Alves, 1974- January 2006 (has links)
Orientador: Dagoberto Martins / Banca: Mario Sergio Tomazela / Banca: Sidnei Roberto de Marchi / Banca: Fernando Tadeu de Carvalho / Banca: Eduardo A. Lemus Erasmo / Resumo: O objetivo deste trabalho foi avaliar a deposição proporcionada por diferentes pontas e volumes de calda de pulverização sobre a cultura do milho e duas espécies de plantas daninhas presentes na linha e entrelinha da cultura em duas épocas de aplicação. O estudo em campo foi conduzido na Faculdade de Ciências Agronômica - FCA/UNESP, campus de Botucatu/SP, e as análises laboratoriais foram realizadas no Núcleo de Pesquisas Avançadas em Matologia / FCA. O milho foi semeado em espaçamento de 0,8 m, com 7 plantas/m. Sementes de Euphorbia heterophylla e Brachiaria plantaginea, foram semeadas e em média obteve-se 222,1 e 164,3 plantas/mø, respectivamente. Os tratamentos foram constituídos de duas pontas (DG 11002VS, TX08) e dois volumes de pulverização (100 e 200 Lha-1). Aos 13 dias após a germinação do milho realizou a primeira aplicação, pulverizando uma calda com corante alimentício azul brilhante FDC-1, a uma concentração de 3000 ppm. Para tal, foi utilizado um pulverizador costal pressurizado a CO2 com pressão constante de 30 l/polø, equipado com uma barra de pulverização com quatro bicos. Após a aplicação, coletaram-se 20 plantas daninhas de ambas as espécies presentes na linha e entrelinha do milho, e em seguida coletaram-se 20 plantas de milho. As plantas coletadas foram colocadas em sacos plásticos nos quais as plantas daninhas foram lavadas com 35,7 ml e o milho com 100 ml de água destilada. Após a lavagem as plantas foram colocadas em sacos de papel e levadas para estufa de ventilação forçada para secagem. Aos 26 dias após o início da germinação do milho realizouse segunda aplicação, com procedimentos idênticos ao da primeira, com exceção para coleta e lavagem. As plantas de milho foram divididas em ápice e base e a quantidade de água de lavagem, nesta ocasião, foi de 100 ml para as plantas daninhas e 300 ml para o milho... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this reseach was to evaluate the deposition of different nozzles and spraying volumes on maize crop and two species of weed in the line and space between lines at two application times. The field trial was carried in the Faculdade de Ciências Agronômica - FCA/UNESP, campus of Botucatu/SP, and the laboratories analyses had been carried through in the Núcleo de Pesquisas Avançadas em Matologia from FCA. The maize was sown in space of 0,8 m, with 7 plants/m. Seeds of Euphorbia heterophylla and Brachiaria plantaginea had been sown and in 164.3 average it got 222.1 plants/mø, respectively. The treatments had been constituted of two nozzles (DG 11002VS, TX08) and two spraying volumes (100 and 200 Lha-1). After 13 days the germination carried through the first application, spraying with brilliant blue FDC-1 tracer solution (3000 ppm). It was used a back pack sprayer pressurized by CO2 at 30 l/polø, equipped with spraying bar with four nozzles. After the application, were collected 20 plants of both weeds and crop in the line and space between lines of the maize. The collected had been put in plastic bags in which the weed had been washed with 35,7 ml and the maize with 100 ml of distilled water. After the plants had been put in bags of paper to drying. After 26 days the germination beginning of the maize carried through the second spraying, with identical procedures to the first one, with exception for the maize plants, which had been divided in apice and base and, the amount of water, with the tracing but in two case had been 100 ml to weed and 300 ml to the maize. The samples obtained were analyzed through spectrophotometer at wavelength of 630 nm. Just to determine the tracer concentration. The plants stadium influenced the spraying drift. In the crop, the spraying deposition was depended of the stadium, type of nozzles and volume of application... (Complete abstract, click electronic access below) / Doutor
166

Distribuição espacial e plano de amostragem sequencial de Pseudoplusia includens (Walker) (Lepidoptera: Noctuidae), em dois sistemas de plantio de soja /

Moura, Jaqueline Zanon de. January 2012 (has links)
Orientador: José Carlos Barbosa / Coorientador: Luiz Evaldo de Moura Pádua / Banca: Arlindo Leal Boiça Júnior / Banca: Francisco Jorge Cividanes / Banca: Marília Gregolim Costa / Banca: Eulália Maria Sousa Carvalho / Resumo: O controle de pragas da soja representa até 36,50% do custo de produção. As lagartas desfolhadoras podem comprometer a produção de soja causando desfolhas de até 100%. A dificuldade de controle, associada ao aumento populacional e seriedade dos danos causados colocam a subfamília Plusiinae em destaque nacional, sendo mais abundante a espécie Pseudoplusia includens (Walker). Portanto, objetivou-se com este trabalho estudar a distribuição espacial da P. includens em dois sistemas de cultivo de soja, bem como, elaborar um plano de amostragem sequencial para a praga. Para monitoramento dos insetos foram realizadas coletas semanais através do método do pano de batida. Estudou-se a distribuição espacial do inseto, através de índices de dispersão e testes de ajuste às principais distribuições de probabilidade. Testaram-se os ajustes às distribuições de Poisson e binomial negativa. Os valores dos índices de dispersão, para lagartas de P. includens, em sistema de plantio convencional de soja, indicaram distribuição agregada para as duas categorias de lagartas (pequenas e grandes). Os resultados na área com sistema de plantio direto foram semelhantes. Desta forma, é possível afirmar que lagartas de P. includens apresentaram disposição agregada no campo independentemente do sistema de plantio. Lagartas de P. includens apresentam disposição agregada no campo independentemente do sistema de plantio. O ajuste do número de lagartas coletadas à distribuição de probabilidades binomial negativa possibilitou a elaboração de plano de amostragem sequencial para monitoramento da praga independentemente do sistema de plantio. O número mínimo de unidades amostrais necessário para tomada de decisão é quatro / Abstract: The soybean pest control represents to 36.50% of the cost of production. The defoliating caterpillars may compromise the production of soy causing defoliation of up to 100%. The difficulty of control, with increased population and seriously damage the subfamily Plusiinae put into national prominence, being the most abundant species Pseudoplusia includens (Walker). Therefore, the aim of this work was to study the spatial distribution of P. includens in two systems of land use, as well as develop a sequential sampling plan for the pest. The insects were collected weekly by the ground cloth method. The spatial distribution of the insect was studied, using dispersion indices and testing the main probability distributions. Tested the adjustments to the distributions of Poisson and negative binomial. The values of aggregation index to P. includens larvae in conventionally tilled soybean indicated aggregated distribution for the two categories of larvae (small and large). The results in the area with no-tillage system were similar. Caterpillars of P. includens present aggregate provision in the field regardless of tillage system. Adjusting the number of caterpillars collected the negative binomial probability distribution enabled the development of sequential sampling plan for monitoring the pest regardless of tillage system. The minimum number of sample units required for decision making is four / Doutor
167

Detection, identification, and mapping of maize streak virus and grey leaf spot diseases of maize using different remote sensing techniques

Dhau, Inos January 2019 (has links)
Thesis (PhD. (Geography)) --University of Limpopo, 2019 / Of late climate change and consequently, the spread of crop diseases has been identified as one of the major threat to crop production and food security in subSaharan Africa. This research, therefore, aims to evaluate the role of in situ hyperspectral and new generation multispectral data in detecting maize crop viral and fungal diseases, that is maize streak virus and grey leaf spot respectively. To accomplish this objective; a comparison of two variable selection techniques (Random Forest’s Forward Variable, (FVS) and Guided Regularized Random Forest: (GRRF) was done in selecting the optimal variables that can be used in detecting maize streak virus disease using in-situ resampled hyperspectral data. The findings indicated that the GRRF model produced high classification accuracy (91.67%) whereas the FVS had a slightly lower accuracy (87.60%) based on Hymap when compared to the AISA. The results have shown that the GRRF algorithm has the potential to select compact feature sub sets, and the accuracy performance is better than that of RF’s variable selection method. Secondly, the utility of remote sensing techniques in detecting the geminivirus infected maize was evaluated in this study based on experiments in Ofcolaco, Tzaneen in South Africa. Specifically, the potential of hyperspectral data in detecting different levels of maize infected by maize streak virus (MSV) was tested based on Guided Regularized Random Forest (GRRF). The findings illustrate the strength of hyperspectral data in detecting different levels of MSV infections. Specifically, the GRRF model was able to identify the optimal bands for detecting different levels of maize streak disease in maize. These bands were allocated at 552 nm, 603 nm, 683 nm, 881 nm, and 2338 nm. This study underscores the potential of using remotely sensed data in the accurate detection of maize crop diseases such as MSV and its severity which is critical in crop monitoring to foster food security, especially in the resource-limited subSaharan Africa. The study then investigated the possibility to upscale the previous findings to space borne sensor. RapidEye data and derived vegetation indices were tested in detecting and mapping the maize streak virus. The results revealed that the use of RapidEye spectral bands in detection and mapping of maize streak virus disease yielded good classification results with an overall accuracy of 82.75%. The inclusion of RapidEye derived vegetation indices improved the classification accuracies by 3.4%. Due to the cost involved in acquiring commercial images, like xviii RapidEye, a freely available Landsat-8 data can offer a new data source that is useful for maize diseases estimation, in environments which have limited resources. This study investigated the use of Landsat 8 and vegetation indices in estimating and predicting maize infected with maize streak virus. Landsat 8 data produced an overall accuracy of 50.32%. The inclusion of vegetation indices computed from Landsat 8 sensor improved the classification accuracies by 1.29%. Overally, the findings of this study provide the necessary insight and motivation to the remote sensing community, particularly in resource-constrained regions, to shift towards embracing various indices obtained from the readily-available and affordable multispectral Landsat-8 OLI sensor. The results of the study show that the mediumresolution multispectral Landsat 8-OLI data set can be used to detect and map maize streak virus disease. This study demonstrates the invaluable potential and strength of applying the readily-available medium-resolution, Landsat-8 OLI data set, with a large swath width (185 km) in precisely detecting and mapping maize streak virus disease. The study then examined the influence of climatic, environmental and remotely sensed variables on the spread of MSV disease on the Ofcolaco maize farms in Tzaneen, South Africa. Environmental and climatic variables were integrated together with Landsat 8 derived vegetation indices to predict the probability of MSV occurrence within the Ofcolaco maize farms in Limpopo, South Africa. Correlation analysis was used to relate vegetation indices, environmental and climatic variables to incidences of maize streak virus disease. The variables used to predict the distribution of MSV were elevation, rainfall, slope, temperature, and vegetation indices. It was found that MSV disease infestation is more likely to occur on low-lying altitudes and areas with high Normalised Difference Vegetation Index (NDVI) located at an altitude ranging of 350 and 450 m.a.s.l. The suitable areas are characterized by temperatures ranging from 24°C to 25°C. The results indicate the potential of integrating Landsat 8 derived vegetation indices, environmental and climatic variables to improve the prediction of areas that are likely to be affected by MSV disease outbreaks in maize fields in semi-arid environments. After realizing the potential of remote sensing in detecting and predicting the occurrence of maize streak virus disease, the study further examined its potential in mapping the most complex disease; Grey Leaf Spot (GLS) in maize fields using WorldView-2, Quickbird, RapidEye, and Sentinel-2 resampled from hyperspectral data. To accomplish this objective, field spectra were acquired from healthy, moderate and xix severely infected maize leaves during the 2013 and 2014 growing seasons. The spectra were then resampled to four sensor spectral resolutions – namely WorldView-2, Quickbird, RapidEye, and Sentinel-2. In each case, the Random Forest algorithm was used to classify the 2013 resampled spectra to represent the three identified disease severity categories. Classification accuracy was evaluated using an independent test dataset obtained during the 2014 growing season. Results showed that Sentinel-2 achieved the highest overall accuracy (84%) and kappa value (0.76), while the WorldView-2, produced slightly lower accuracies. The 608 nm and 705nm were selected as the most valuable bands in detecting the GLS for Worldview 2, and Sentinel-2. Overall, the results imply that opportunities exist for developing operational remote sensing systems for detection of maize disease. Adoption of such remote sensing techniques is particularly valuable for minimizing crop damage, improving yield and ensuring food security.
168

Volumes de aplicação, pontas de pulverização e adjuvantes no controle de Enneothrips flavens Moulton, 1941 (Thysanoptera: Thrypidae) na cultura do amendoim /

Calore, Ricardo Aparecido. January 2013 (has links)
Orientador: Marcelo da Costa Ferreira / Coorientador: Júlio César Galli / Banca: Arlindo Leal Boiça Júnior / Banca: Daniel Andrade / Banca: Carlos Gilberto Raetano / Banca: Otavio Jorge Grigoli Abi Saab / Resumo: O tripes Enneothrips flavens Moulton, 1941 (Thysanoptera: Thrypidae), é considerado uma das principais pragas da cultura do amendoim. A aplicação de inseticidas, principal método de controle, requer o conhecimento de diversas características da tecnologia de aplicação para manter a eficiência do tratamento fitossanitário. Diante disso, objetivou-se avaliar o efeito de volumes de aplicação, modelos de pontas de pulverização e adjuvantes na cobertura, no depósito de calda e no controle de E. flavens na cultura do amendoim. No primeiro experimento (safra 2011/2012) utilizou-se um inseticida sistêmico para controle do tripes, três modelos de pontas de pulverização (XR, LD e ADIA), três volumes de aplicação (80, 100 e 130 L.ha-1) e duas testemunhas: um tratamento que não recebeu o inseticida e outro tratamento convencional, cujo volume de aplicação foi de 250 L.ha-1. A partir dos resultados obtidos no primeiro experimento, fixou-se o modelo de ponta de pulverização e o volume de calda que foram mais adequados para o controle de E. flavens para o experimento realizado na safra 2012/2013, no qual utilizou-se adjuvantes (óleo vegetal, óleo mineral e tributyl citrate + polydimethylsiloxane) na calda inseticida. Nos dois experimentos foram realizadas a avaliação da cobertura da cultura pela calda pulverizada, por análise de imagem de papéis hidrossensíveis. Para avaliação do depósito de calda sobre as folhas de amendoim foi adicionado o marcador sulfato de manganês às caldas de pulverização, posteriormente extraído para análise por espectrofotometria. Os dados da porcentagem de cobertura, de depósito, das notas de danos causados por E. flavens e de produtividade da cultura, foram submetidos à análise de variância e os tratamentos comparados pelo teste de Tukey, a 5% de significância. Concluiu-se que: a) Nas aplicações a campo visando o controle de E. flavens ... / Abstract: The thrips Enneothrips flavens Moulton, 1941 (Thysanoptera: Thrypidae) is considered the main pest of the peanult crop. The application of pesticides, the most used control method, requires a broad knowledge of the characteristics of the application technology to keep the efficiency of phytosanitary treatment. Therefore this paper aimed to evaluate the effect of spray volumes, spray nozzles and adjuvants on coverage, the spray deposition and the control of E. flavens on peanut crop. In the first experiment (2011/2012 season) was used a systemic insecticide to control of thrips, three models of spray nozzles (XR, LD and ADIA), three spraying volumes (80, 100 and 130 L.ha-1) and two controls: a treatment that no received insecticide and other conventional treatment whose the spray volume was 250 L.ha-1. From the results obtained in the first experiment, we fixed the model of nozzle and spray volume that were more suitable for the control of E. flavens and other experiment was conducted in 2012/2013 season, which was used adjuvants (vegetable oil, mineral oil and tributyl citrate + polydimethylsiloxane) in spray insecticide. In both experiments were evaluated the coverage of the plants from spraying liquid by analysis of image of hydrosensitive papers. For evaluation of spray deposit on the leaves of peanut it was added manganese sulfate as tracer to the spray liquid and subsequently extracted by analysis of expectrofotometry. The data of the deposit, percentage of coverage, notes of damage caused by E. flavens and crop yield were subjected to analysis of variance and the treatments compared by Tukey test at 5% of significance level. It was concluded that: a) In the field application for the control of E. flavens in the peanuts cultivation of creeping growth, the spraying volume can be reduced to 80 L.ha-1 using the insecticide thiamethoxam + lambda-cyhalothrin at it recommended dosage, with the ... / Doutor
169

Flutuação populacional e distribuição espacial de Diaphorina citri Kuwayama (Hemiptera: Liviidae) em propriedades citrícolas com manejo intensivo do Huanglongbing /

Santos, Tiago Roberto dos. January 2013 (has links)
Orientador: Francisco Jorge Cividanes / Coorientador: José Carlos Barbosa / Banca: Nilza Maria Martinelli / Banca: Pedro Takao Yamamoto / Resumo: O psilídeo asiático dos citros Diaphorina citri Kuwayama (Hemiptera: Liviidae) e, atualmente, considerado a principal praga da citricultura mundial, podendo causar perdas de até 100% na produção. O inseto causa danos diretos, através da sucção de seiva de brotações, contudo sua maior importância está relacionada aos danos indiretos, devido à transmissão da bactéria "Candidatus Liberibacter", associada ao greening ou Huanglongbing (HLB). 0 objetivo deste estudo foi avaliar a flutuação populacional e distribuição espacial de adultos de D. citri em áreas citrícolas do sul e centro do Estado de São Paulo sob controle químico convencional. As avaliações foram realizadas no período de 01 de julho de 2010 a 31 de dezembro de 2012 em duas áreas comerciais de plantio de citros, com 9.004 e 5.495 hectares, localizadas nos municípios de laras e Boa Esperança do Sul, respectivamente. Para a quantificação dos adultos de D. citri, foram instaladas armadilhas adesivas nas bordaduras dos lotes, sendo realizadas avaliações semanais. Os picos populacionais ocorreram na primavera e verão, período com maior número de brotações. As aplicações de inseticidas não alteraram o padrão de distribuição de D. citri. Os valores dos índices de agregação indicaram que o inseto se comporta de maneira altamente agregada na cultura / Abstract: The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is currently considered the major world pest of citriculture and can cause yield losses of up to 100%. The insect causes direct damage by consuming sap from shoots, although its greater importance is related to indirect damage due to the transmission of the bacterium "Candidatus Liberibacter" which are associated to causes the greening or Huanglongbing (HLB). The aim of the study was to evaluate the population fluctuation and spatial distribution of D. citri adults in citrus farming areas of the south and center regions of São Paulo state under conventional chemical control. The evaluations were performed in the period from july 01, 2010 to December 31, 2012 in two areas of citrus commercial planting, with 9,004 and 5,495 hectares, located in the municipalities of laras and Boa Esperança do Sul, respectively. To quantify D. citri adults, yellow sticky traps were assembled on the borders of the lots, and were weekly evaluated by pest inspectors. The population peaks occurred in spring and summer, periods with higher number of new shoots. The insecticides applications did not alter the distribution pattern of D. citri. The values of aggregation index indicated that the insect has a highly aggregate behavior in citriculture / Mestre
170

Avaliação de resistência de cultivares de cana-de-açúcar ao Sugarcane yellow leaf virus (SCYLV) e ao seu afídeo vetor Melanaphis sacchari

Rodrigues, Mariana Pelegrini [UNESP] 21 May 2015 (has links) (PDF)
Made available in DSpace on 2015-12-10T14:22:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-21. Added 1 bitstream(s) on 2015-12-10T14:28:37Z : No. of bitstreams: 1 000855237.pdf: 1808064 bytes, checksum: fcc5213095846f3cb1af0f6237332f31 (MD5) / Este trabalho teve como tema a avaliação da resistência de cultivares de cana-de-açúcar (Saccharum sp.) ao vírus do amarelecimento foliar (SCYLV) e ao seu principal afídeo vetor Melanaphis sacchari (Zehntner). Cinco cultivares de cana-de-açúcar (IACSP93 3046, IACSP95 5000, IACSP95 5094, IACSP96 3076 e SP71 6163) escolhidas devido à importância econômica para os canaviais brasileiros, foram multiplicadas por cultura de meristema e indexadas em uma biofábrica e avaliadas quanto à resistência ao seu inseto vetor M. sacchari, por meio do estudo do comportamento deste afídeo nessas cultivares através de testes de antibiose, antixenose e EPG (Eletrical Penetration Graphs). Paralelamente, um segundo ensaio foi estabelecido para avaliar o desenvolvimento do amarelecimento foliar em campo, após inoculação do vírus (SCYLV) nas plantas indexadas. Os pulgões mostraram uma preferência para a cultivar IACSP96 3076 e melhor desenvolvimento populacional na IACSP95 5000. Parâmetros floemáticos favoráveis ao desenvolvimento de M. sacchari foram descobertos na cultivar SP71 6163 reforçando sua suscetibilidade a infecção de SCYLV, e comprovando por meio de avaliações de severidade de sintomas, que o amarelecimento da cana-de-açúcar expressa-se com maior rapidez e intensidade nesta cultivar / This research focused on the evaluation of resistance in sugarcane (Saccharum spp.) to the Sugarcane yellow leaf virus (SCYLV) and to its main vector, the sugarcane aphid Melanaphis sacchari (Zehntner). Five sugarcane varieties (IACSP93 3046, IACSP95 5000, IACSP95 5094, IACSP96 3076, and SP71 6163), chosen due to their economic importance to Brazilian sugarcane growing areas, were multiplied by tissue tip culture, indexed, and evaluated in terms of the aphids' behavior by the traditional antibiosis, antixenosis and EPG (Electrical Penetration Graphs). At the same time, a second test was set up for evaluating the development of yellowing leaf on field after inoculation with SCYLV. The aphid showed preference for IACSP96 3076 and higher population growths indexes on IACSP95 5000. We found out favorable parameters on the insect behavior over variety SP71 6163 that reinforce its previously known high susceptibility to SCYLV infection. We also demonstrate by these experiments the existence of pre and post-phloematic penetration factors that influence the behavior of M. sacchari and further transmission of SCYLV, and proving through initial assessments of symptoms severity that YLS yellowing of sugarcane expressed faster and more strongly in this cultivar

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