Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2017-08-11T13:01:57Z No. of bitstreams: 1 PDF - Jonnathan Whiny Moraes dos Santos.pdf: 20146290 bytes, checksum: 1be326dec739963cb441a03e24a0f84c (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2017-08-29T15:45:18Z (GMT) No. of bitstreams: 1 PDF - Jonnathan Whiny Moraes dos Santos.pdf: 20146290 bytes, checksum: 1be326dec739963cb441a03e24a0f84c (MD5) / Made available in DSpace on 2017-08-29T15:45:18Z (GMT). No. of bitstreams: 1 PDF - Jonnathan Whiny Moraes dos Santos.pdf: 20146290 bytes, checksum: 1be326dec739963cb441a03e24a0f84c (MD5) Previous issue date: 2017-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Belonging to the Fabaceae family, the peanut (Arachis hypogaea) is cultivated worldwide, having great importance in the income of the cultivator. Because it is a culture that associates with bacteria that have the capacity to fix nitrogen, it has been studied in order to potentiate this symbiotic relationship and favor the increase of its production. Thus the objective of this work was to evaluate the diversity and symbiotic efficiency of the native bacteria associated with Arachis species. A collection of bacteria isolated from nodules of six species of the genus Arachis cultivated in samples of six soils from the semi - arid region was structured. The isolates were purified and evaluated for their phenotypic characteristics, and amplification of some symbiotic genes. The isolates considered as nifH, nodA and / or nodC positive we re selected for the symbiotic efficiency test, as well as for the partial sequencing reactions of the 16S rRNA gene. Bacteria selected in previous evaluations were tested in a greenhouse experiment to evaluate symbiotic efficiency. Bacteria classified as Bradyrhizobium, the 16S rRNA gene were also sequenced in reverse. In addition, the recA, nifD and nodC genes were also amplified and sequenced. For these same isolates, a BOX-PCR was performed to verify differences between these isolates. Phylogenetic trees were elaborated based on the genes gathered from the results. A collection of 365 isolates was obtained, with the majority of the isolates showing rapid growth, acidifying the culture medium, colony diameter of 1 to 2 mm, and yellowing. Of the total isolates, 253 had amplification in at least one of the evaluated symbiotic genes, 94 isolates amplified for all genes and primers evaluated. A total of 63 isolates were selected for sequencing of the 16S rRNA gene, as well as for the evaluation of symbiotic efficiency in greenhouse. From the obtained results, 45 sequences presented good quality and adequate size and were used for the comparison with those available in the EzBioCloud database. A total of 22 isolates were identified as belonging to the genus Bradyrhizobium, with 21 being classified in the clade I B. japonicum and only 1 in the clade II B. elkanii, and 23 others belonging to non-rhizobian genera. From the sequencing of the symbiotic genes, it was found that some isolates that had amplifications in the three evaluated genes, such as the isolates S2AB2, S2AD2, S2AH 9.1 and S2AH 4.1, remained in distinct groups in all three symbiotic gene trees, as well as in the 16S rRNA gene tree, confirming the low similarity of these isolates to the type strains, indicating that they are possibly isolated from new species. With the BOX-PCR it was confirmed that the isolates presented a high degree of polymorphism, and that these were actually different isolates. The isolates tested in greenhouse were able to nodulate commercial cultivar BR1. The co- inoculation with non-rhizobial bacteria may have favored some isolates in their symbiotic efficiency, mainly in the accumulation of N in plants. These results will support studies for future evaluations of the selected isolates in the recommendation of inoculants of native species for the peanut crop. Cultivated peanuts and wild species evaluated may establish symbiotic associations with native strains of rhizobia with high diversity and symbiotic efficiency. / Pertencente à família Fabaceae o amendoim (Arachis hypogaea) é cultivado mundialmente, tendo grande importância na geração de renda do produtor. Por ser uma cultura que se associa a bactérias que têm a capacidade de fixar nitrogênio, vem sendo estudada visando potencializar essa relação simbiótica e favorecer o aumento de sua produção. Dessa forma o objetivo desse trabalho foi avaliar a diversidade e a eficiência simbiótica de bactérias nativas associadas a espécies de Arachis. Foi estruturada uma coleção de bactérias isoladas de nódulos de 6 espécies do gênero Arachis cultivadas em amostras de 6 solos da região semiárida. Os isolados foram purificados e avaliados quanto às suas características fenotípicas, e amplificação de alguns genes simbióticos. Os isolados considerados nifH, nodA e/ou nodC positivos foram selecionados para o teste de eficiência simbiótica, assim como para as reações de sequenciamento parcial do gene 16S rRNA. Bactérias selecionadas nas avaliações anteriores foram testadas em um experimento em casa de vegetação para avaliar a eficiência simbiótica. As bactérias classificadas como Bradyrhizobium, o gene 16S rRNA foi sequenciado também no sentido reverso. Além disso, foram amplificados e sequenciados também, os genes recA, nifD e nodC. Para estes mesmos isolados, foi realizado um BOX-PCR, para verificar diferenças entre esses isolados. A partir desses resultados foram elaboradas as árvores filogenéticas com base nesses genes. Uma coleção de 365 isolados foi obtida sendo que a maioria dos isolados apresentaram crescimento rápido, acidificaram o meio de cultura, tinham diâmetro de colônia de 1 a 2mm, além de apresentarem coloração amarela. Do total de isolados, 253 tiveram amplificação em pelo menos uns dos genes simbióticos avaliados, 94 isolados amplificaram para todos os genes e iniciadores avaliados. Um total de 63 isolados foram selecionados para sequenciamento do gene 16S rRNA, assim como para a avaliação da eficiência simbiótica em casa de vegetação. A partir dos resultados obtidos, 45 sequências apresentaram boa qualidade e tamanho adequado e foram utilizadas para a comparação com aquelas disponíveis no banco de dados EzBioCloud. Um total de 22 isolados foram identificados como pertencentes ao gênero Bradyrhizobium, sendo 21 enquadrados no clado I B. japonicum e apenas 1 no clado II B. elkanii, e outros 23 como pertencentes a gêneros não rizobianos. A partir do sequenciamento dos genes simbióticos, verificou-se que alguns isolados que tiveram amplificações nos três genes avaliados, como os isolados S2AB2, S2AD 2, S2AH 9.1 e S2AH 4.1, permaneceram em grupos distintos em todas as três árvores dos genes simbióticos, assim como também na árvore do gene 16S rRNA, confirmando a baixa similaridade desses isolados com as estirpes tipo, indicando que são possivelmente isolados de novas espécies. Com o BOX-PCR foi confirmado que os isolados apresentavam alto grau de polimorfismo, e que estes realmente eram isolados diferentes. Os isolados testados em casa de vegetação foram capazes de nodular a cultivar comercial BR 1. A coinoculação com bactérias não rizobianas pode ter favorecido alguns isolados, em sua eficiência simbiótica, principalmente no acúmulo de N nas plantas. Estes resultados subsidiarão estudos para futuras avaliações dos isolados selecionados na recomendação de inoculantes de espécies nativas para a cultura do amendoim. O amendoim cultivado e as espécies silvestres avaliadas podem estabelecer associações simbióticas com estirpes nativas de rizóbios com elevada diversidade e eficiência simbiótica.

Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-12-04T13:28:18Z No. of bitstreams: 2 Dissertação - Eloene Rodrigues Godoy - 2016.pdf: 2017416 bytes, checksum: 606092ba846fd0631f779cc9e9fc7264 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-12-05T09:59:25Z (GMT) No. of bitstreams: 2 Dissertação - Eloene Rodrigues Godoy - 2016.pdf: 2017416 bytes, checksum: 606092ba846fd0631f779cc9e9fc7264 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-12-05T09:59:25Z (GMT). No. of bitstreams: 2 Dissertação - Eloene Rodrigues Godoy - 2016.pdf: 2017416 bytes, checksum: 606092ba846fd0631f779cc9e9fc7264 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-12-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed to evaluate the performance of six peanut lines and two cultivars based on production indicators, in an organic system of transition in the region of Jataí – GO. The experiment was conducted at Universidade Federal de Goiás - Campi Jataí, and implemented on November 30th, 2015. The experimental design has happened with randomized blocks (RBD) with eight treatments (2012-38, 2012-71; 2013-293, 2013-415; 2013-413 OL; 2013-415 OL), and with the commercial varieties Runner IAC 886 and IAC 505 in four replications. The characteristics evaluated are divided into two categories: (a) Productivity, measured by weighing the parcel; and (b) Weight of 100 pods; weight of seeds in 100 pods and the weight of 100 seed. After the sowing time, period of 88, 119 and 140 days, the weighing of fresh and dry matter of fruit, stem and roots have been made. During the cycle of the plants, there were photographic records for the growth and coverage factor analysis. The manual harvesting process of the crop, on April 28th, 2016 (corresponding to 140 days after sowing), happened when 60% to 70% of the pods presented brown color pigments inside. Through linear regression, it was possible to estimate the fruiting period by subtracting the days of maturity (harvest) from the fruiting ones. The evaluated strains differ statistically with a emphasis on the lineage 13-425OL productivity. Based on the parameters studied, the strains have the potential to be cultivated through the organic system. Fungal diseases caused significant losses on the coverage factor. / Nessa pesquisa objetivou-se avaliar o desempenho de seis linhagens de amendoim e duas cultivares, com base em indicadores produtivos, em sistema de transição orgânico na região de Jataí- GO. O experimento foi conduzido na Universidade Federal de Goiás - Regional Jataí, e implantado no dia 30 de novembro de 2015. O Delineamento experimental foi em Blocos Casualizados (DBC) com oito tratamentos (2012-38; 2012-71; 2013-293; 2013-415; 2013-413 OL; 2013- 415 OL), e com as variedades comerciais Runner IAC 886 e IAC 505 em quatro repetições. As características avaliadas se dividem em duas categorias: (a) Produtividade: avaliada através de pesagens do peso de vagens das parcelas, e (b) peso de 100 vagens, peso das sementes em 100 vagens e o peso de 100 sementes; Aos 88, 119 e 140 dias após a semeadura, foram feitas pesagens de matéria fresca e seca de frutos, assim como caules e raízes. Durante todo o ciclo das plantas, houve registros fotográficos para análise de crescimento e fator de cobertura. A colheita realizada, no dia 28 de abril de 2016 (correspondente a 150 dias após a semeadura), aconteceu quando 60% a 70% das vagens apresentavam pigmentos de cor marrom na parte interna. Por meio dos parâmetros de regressão, foi possível estimar o período de frutificação ao subtrair os dias de maturação (colheita) dos dias de frutificação. As linhagens avaliadas diferiram estatisticamente, com destaque maior de produtividade na linhagem 13-425OL. Com base nos parâmetros estudados, as linhagens apresentam potencial para serem cultivadas sob o sistema orgânico. As doenças fúngicas causaram perdas significativas no fator de cobertura.

Stem rot of peanut (Arachis hypogaea L.), caused by a soilborne fungus Athelia rolfsii (Curzi) C. C. Tu and Kimbr. (anamorph: Sclerotium rolfsii Sacc.), is one of the most important diseases in peanut production worldwide. Though new varieties with increased partial resistance to this disease have been developed, there is still a need to utilize fungicides for disease control during the growing season. Fungicides with activity against A. rolfsii are available, and several new products have been recently registered for control of stem rot in peanut. However, fungicides are most effective when applied before or during the early stages of infection. Current scouting methods can detect disease once signs or symptoms are present, but to optimize the timing of fungicide applications and protect crop yield, a method for early detection of soilborne diseases is needed. Previous studies have utilized optical sensors combined with machine learning analysis for the early detection of plant diseases, but these studies mainly focused on foliar diseases. Few studies have applied these technologies for the early detection of soilborne diseases in field crops, including peanut. Thus, the overall goal of this research was to integrate sensor technologies, modern data analytic tools, and properties of standard and newly registered fungicides to develop improved management strategies for stem rot control in peanuts. The specific objectives of this work were to 1) characterize the spectral and thermal responses of peanut to infection with A. rolfsii under controlled conditions, 2) identify optimal wavelengths to detect stem rot of peanut using hyperspectral sensor and machine learning, and 3) evaluate the standard and newly registered peanut fungicides with different modes of action for stem rot control in peanuts using a laboratory bioassay. For Objective 1, spectral reflectance and leaf temperature of peanut plants were measured by spectral and thermal sensors in controlled greenhouse experiments. Differences in sensor-based responses between A. rolfsii-infected and non-infected plants were detected 0 to 1 day after observation of foliar disease symptoms. In addition, spectral responses of peanut to the infection of A. rolfsii were more pronounced and consistent than thermal changes as the disease progressed. Objective 2 aimed to identify specific signatures of stem rot from reflectance data collected in Objective 1 utilizing a machine learning approach. Wavelengths around 505, 690, and 884 nm were repeatedly selected by different methods. The top 10 wavelengths identified by the recursive feature selection methods performed as well as all bands for the classification of healthy peanut plants and plants at different stages of disease development. Whereas the first two objectives focused on disease detection, Objective 3 focused on disease control and compared the properties of different fungicides that are labeled for stem rot control in peanut using a laboratory bioassay of detached peanut tissues. All of the foliar-applied fungicides evaluated provided inhibition of A. rolfsii for up to two weeks on plant tissues that received a direct application. Succinate dehydrogenase inhibitors provided less basipetal protection of stem tissues than quinone outside inhibitor or demethylation inhibitor fungicides. Overall, results of this research provide a foundation for developing sensor/drone-based methods that use disease-specific spectral indices for scouting in the field and for making fungicide application recommendations to manage stem rot of peanut and other soilborne diseases. / Doctor of Philosophy / Plant diseases are a major constraint to crop production worldwide. Developing effective and economical management strategies for these diseases, including selection of proper fungicide chemistries and making timely fungicide application, is dependent on the ability to accurately detect and diagnose their signs and/or symptoms prior to widespread development in a crop. Optical sensors combined with machine learning analysis are promising tools for automated crop disease detection, but research is still needed to optimize and validate methods for the detection of specific plant diseases. The overarching goal of this research was to use the peanut-stem rot plant disease system to identify and evaluate sensor-based technologies and different fungicide chemistries that can be utilized for the management of soilborne plant diseases. The specific objectives of this work were to 1) characterize the temporal progress of spectral and thermal responses of peanut to infection and colonization with Athelia rolfsii, the causal agent of peanut stem rot 2) identify optimal wavelengths to detect stem rot of peanut using hyperspectral sensor and machine learning, and 3) evaluate standard and newly registered peanut fungicides with different modes of action for stem rot control in peanuts using a laboratory bioassay. Results of this work demonstrate that spectral reflectance measurements are able to distinguish between diseased and healthy plants more consistently than thermal measurements. Several wavelengths were identified using machine learning approaches that can accurately differentiate between peanut plants with symptoms of stem rot and non-symptomatic plants. In addition, a new method was developed to select the top-ranked, non-redundant wavelengths with a custom distance. These selected wavelengths performed better than using all wavelengths, providing a basis for designing low-cost optical filters to specifically detect this disease. In the laboratory bioassay evaluation of fungicides, all of the foliar-applied fungicides provided inhibition of A. rolfsii for up to two weeks on leaf tissues that received a direct application. Percent inhibition of A. rolfsii decreased over time, and the activity of all fungicides decreased at a similar rate. Overall, the findings of this research provide a foundation for developing sensor-based methods for disease scouting and making fungicide application recommendations to manage stem rot of peanut and other soilborne diseases.

Orientador: Arlindo Leal Boiça Junior / Banca: Antonio Carlos Busoli / Banca: André Luiz Lourenção / Resumo: Este trabalho teve como objetivo avaliar possíveis fontes de resistência de cultivares de amendoim de hábitos de crescimento ereto e rasteiro, a Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) dos tipos não-preferência para oviposição, alimentação (com e sem chance de escolha) e antibiose. Os experimentos foram conduzidos em laboratório, sob condições controladas de temperatura (25 ± 2°C), umidade (60 ± 10%) e fotofase (12 horas). Foram utilizadas cultivares de amendoim de hábitos de crescimento ereto (IAC 5, IAC 8112, IAC 22 e IAC Tatu ST) e rasteiro (IAC 503, IAC 505, IAC 147, IAC 125, IAC Caiapó e IAC Runner 886). Estas cultivares foram avaliadas separadamente devido ao hábito de crescimento do material em todos os testes. Os testes de não-preferência para oviposição foram realizados com adultos recém-emergidos, os quais foram alimentados com solução de mel a 10%, permanecendo nas gaiolas por quatro dias até o início das avaliações. Estas consistiram na quantificação do número de ovos e posturas, com posterior cálculo do número de ovos por postura. Para os testes de não-preferência para alimentação foram colocados discos foliares das cultivares em placas de Petri, liberando uma lagarta de terceiro ínstar por cultivar. Avaliou-se a atratividade a 1; 5; 10; 15; 30; 60; 120; 360; 720; 1440 minutos, contando o número de lagartas que se alimentavam nas cultivares e, ao término do experimento, quantificou-se a área foliar consumida por cultivar. No teste de antibiose, além da identificação de cultivares de amendoim resistentes a S. frugiperda, determinaram-se, também, os graus de resistência através da análise multivariada. As cultivares foram semeadas em campo. Lagartas de primeiro ínstar foram individualizadas em placas de Petri forradas com papel filtro umedecido. Diariamente, foram fornecidos folíolos novos. Avaliaram-se... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to evaluate possible sources of resistance of peanut cultivars of the upright growth and runner growth habit, to Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) by non-oviposition and non-feeding preference (tests choice and no-choice) and antibiosis. The experiments were conducted in laboratory under controlled conditions of temperature (25 ± 2°C), humidity (60 ± 10%) and photophase (12 hours). Peanut cultivars of upright growth habit (IAC 5, IAC 8112, IAC 22 and IAC Tatu ST) and runner growth habit (IAC 503, IAC 505, IAC 147, IAC 125, IAC Caiapó and IAC Runner 886) were evaluated. These cultivars were evaluated separately due to the material growth habit in all tests. Tests of non-oviposition preference were conducted with newly emerged adults, and they were fed with a 10% honey solution, remaining in the cages for four days until the start of evaluations. Evaluations consisted of quantifying the eggs and egg masses numbers, followed by calculation the number of eggs per egg masses. To perform non-feeding preference tests, leaves discs from different cultivars were placed in disposable Petri dishes followed by releasing of a third instar caterpillar for each cultivar. The attractiveness at 1; 5; 10; 15; 30; 60; 120; 360; 720 and 1,440 minutes was evaluated by counting the caterpillars number which were fed on cultivars, quantified the leaf area consumed by cultivar was evaluated at the end of the experiment. Additionally, identification of peanuts cultivars resistance to S. frugiperda, and the resistance degree was evaluated by multivariate analysis of the antibiosis test. The cultivars were planted in plots on the field. First instar larvae were placed individually in disposable Petri dishes plates, over a moistened filter paper. New leaflets were provided every day. The duration (days), weight (mg) and viability... (Complete abstract click electronic access below) / Mestre

Submitted by (ana.araujo@ufrpe.br) on 2017-02-17T12:38:37Z No. of bitstreams: 1 Jacqueline Wanessa de Lima Pereira.pdf: 684135 bytes, checksum: dc0f8da93d2685268558a2dc803e4044 (MD5) / Made available in DSpace on 2017-02-17T12:38:37Z (GMT). No. of bitstreams: 1 Jacqueline Wanessa de Lima Pereira.pdf: 684135 bytes, checksum: dc0f8da93d2685268558a2dc803e4044 (MD5) Previous issue date: 2010-07-07 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Peanut is one of the most cultivated oily in the world. For countries of semi-arid climate, as Brazil, for example, the peanut is an important alternative to farming due to the low water requirement during the cycle and adaptation to environments of high temperature and solar radiation. Despite the tolerance to low water availability, peanuts’ requirements are not the same over the cycle. Water shortage during the reproductive phase directly affects the formation and filling of pods, even in cultivars notoriously resistant to water deficit. According to some authors, which makes the peanut plant tolerant to environmental adversities are the morphological and physiological mechanisms that maintain the plant turgidity, even under low water availability conditions. Among those are cited changes in water ratios (stomatal behavior and osmotic adjustment) and the expansion of the root system for deeper and wetter soil areas. Faced with this adaptability, understanding the role of water deficit during the production cycle of culture is essential for adopting management strategies that enable secure production in areas prone to drought. In this work, four peanut genotypes of different growth habits were subjected to 21 days of water stress in a greenhouse. The planting was performed in pots containing sandy-loam texture soil, previously limed and fertilized. The experimental design was randomized with a bi-factorial 4x2 scheme (4 genotypes x 2 water treatments) with 10 repetitions. the water treatment were control (daily irrigation) and stress (irrigation suspension). The variables evaluated were difusive resistance, transpiration, leaf water potential, relative water content, proline content, chlorophyll content, root length, dry weight of pods, harvest index and stress tolerance index (STI). Under stress conditions, stomatal behavior was changed from the second week, when all genotypes significantly increased abaxial surface diffusive resistance and reduced sweating, highlighting the isoline LBM Branco Moita/08. The water potential of all genotypes was significantly reduced, being more expressive in isolines LBM-Branco Moita/08 and LBR-Branco Rasteiro/08 reaching more negative values. The LBM-Branco Moita/08 also had higher levels of proline and along with a BR 1 had the greatest expansion of the root system as adaptive way. In the production aspect, the LBM-Branco Moita/08 revealed the lowest reductions in weight of pods and harvest index when subjected to water deficit. Regarding the STI, values obtained with the cv. BR1 confirm its suitability for management in semi-arid environments; the strains LBR-Branco Rasteiro/08 and LBM-Branco Moita/08 also showed significant production performance in environments with water restriction. / O amendoim é uma das oleaginosas mais cultivadas no mundo. Para os países de clima semi-árido, o Brasil, por exemplo, o amendoim é uma importante alternativa para a agricultura devido à baixa exigência hídrica durante o ciclo e adaptação aos ambientes com altas temperaturas e radiação solar. Apesar da tolerância à baixa disponibilidade hídrica, as exigências do amendoim não são as mesmas ao longo do ciclo. A escassez de água durante a fase reprodutiva afeta diretamente a formação e o enchimento das vagens, mesmo em cultivares notoriamente resistentes ao déficit hídrico. Segundo alguns autores, o que torna a planta do amendoim tolerante às adversidades ambientais são os mecanismos morfológicos e fisiológicos que mantêm a turgescência das plantas, mesmo sob condições de baixa disponibilidade de água. Entre as mudanças já estão em relações hídricas (comportamento estomático e ajustamento osmótico) e a expansão do sistema radicular para as áreas mais profundas e úmidas do solo. Confrontados com esta capacidade de adaptação, a compreensão do papel do déficit hídrico durante o ciclo produtivo da cultura é essencial para a adoção de estratégias de manejo que permitam uma produção segura em áreas propensas à seca. Neste trabalho, quatro genótipos de amendoim de diferentes hábitos de crescimento foram submetidos a 21 dias de estresse hídrico em casa de vegetação. O plantio foi realizado em vasos contendo solo de textura franco-arenosa, previamente corrigido e adubado. O delineamento experimental foi inteiramente casualizado, com um esquema bi-fatorial 4x2 (4 genótipos x 2 tratamentos de água), com 10 repetições. Os tratamentos hídricos foram: controle (rega diária) e estresse (suspensão de rega). As variáveis avaliadas foram: resistência difusiva, transpiração, potencial hídrico, teor relativo de água, teor de prolina, teor de clorofila, comprimento radicular, peso seco das vagens, índice de colheita e índice de tolerância ao stress (STI). Sob condições de estresse, comportamento estomático foi alterado a partir da segunda semana, quando todos os genótipos aumentaram significativamente a resistência difusiva da superfície abaxial e reduziram a transpiração, destacando a isolinha LBM-Branco Moita/08. O potencial de água de todos os genótipos foi significativamente reduzido, sendo mais expressivos em isolinhas LBM-Branco Moita/08 e LBR-Branco Rasteiro/08 atingindo valores mais negativos. A LBM-Branco Moita/08 também apresentou elevado acúmulo de prolina e, juntamente com um BR 1 teve a maior expansão do sistema radicular como forma de adaptação. No aspecto de produção, a LBM-Branco Moita/08 revelou as menores reduções no peso das vagens e índice de colheita, quando submetida ao déficit hídrico. Quanto ao STI, os valores obtidos com a cv. BR1 confirmar a sua aptidão para o manejo em ambientes semi-árido, as isolinhas LBR-Branco Rasteiro/08 e LBM-Branco Moita/08 também apresentaram desempenho significativo de produção em ambientes com restrição hídrica.

Groundnut or peanut (Arachis hypogaea L.) is an important legume cultivated in several developing countries in the tropics and subtropics. It plays a significant role as a food crop in regions with alarming population growth rates. The disease “peanut clump”, which is caused by viruses in the genus Pecluvirus, has been reported from India and from several countries of West Africa. In India, the causal agent is the Indian peanut clump virus (IPCV), which is transmitted by a soil-borne root parasite, Polymyxa graminis. The virus is also transmitted by infected seed and so far no economical method of control has been found. Therefore efforts have been concentrated on understanding the epidemiology of peanut clump disease with the aim of devising cultural methods of control. The work addressed in this thesis describes how investigation in various aspects of clump disease epidemiology, including identification of alternative hosts of the virus and the vector, and of factors that contribute to survival and spread of inoculum, has led to formulation of simple cultural practices that could reduce disease incidence.

Groundnut or peanut (Arachis hypogaea L.) is an important legume cultivated in several developing countries in the tropics and subtropics. It plays a significant role as a food crop in regions with alarming population growth rates. The disease “peanut clump”, which is caused by viruses in the genus Pecluvirus, has been reported from India and from several countries of West Africa. In India, the causal agent is the Indian peanut clump virus (IPCV), which is transmitted by a soil-borne root parasite, Polymyxa graminis. The virus is also transmitted by infected seed and so far no economical method of control has been found. Therefore efforts have been concentrated on understanding the epidemiology of peanut clump disease with the aim of devising cultural methods of control. The work addressed in this thesis describes how investigation in various aspects of clump disease epidemiology, including identification of alternative hosts of the virus and the vector, and of factors that contribute to survival and spread of inoculum, has led to formulation of simple cultural practices that could reduce disease incidence.

Made available in DSpace on 2014-06-11T19:25:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-16Bitstream added on 2014-06-13T18:53:09Z : No. of bitstreams: 1 campos_ap_me_jabo.pdf: 283557 bytes, checksum: 460ed3df0cf7a95babadb02e25a47755 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho teve como objetivo avaliar possíveis fontes de resistência de cultivares de amendoim de hábitos de crescimento ereto e rasteiro, a Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) dos tipos não-preferência para oviposição, alimentação (com e sem chance de escolha) e antibiose. Os experimentos foram conduzidos em laboratório, sob condições controladas de temperatura (25 ± 2°C), umidade (60 ± 10%) e fotofase (12 horas). Foram utilizadas cultivares de amendoim de hábitos de crescimento ereto (IAC 5, IAC 8112, IAC 22 e IAC Tatu ST) e rasteiro (IAC 503, IAC 505, IAC 147, IAC 125, IAC Caiapó e IAC Runner 886). Estas cultivares foram avaliadas separadamente devido ao hábito de crescimento do material em todos os testes. Os testes de não-preferência para oviposição foram realizados com adultos recém-emergidos, os quais foram alimentados com solução de mel a 10%, permanecendo nas gaiolas por quatro dias até o início das avaliações. Estas consistiram na quantificação do número de ovos e posturas, com posterior cálculo do número de ovos por postura. Para os testes de não-preferência para alimentação foram colocados discos foliares das cultivares em placas de Petri, liberando uma lagarta de terceiro ínstar por cultivar. Avaliou-se a atratividade a 1; 5; 10; 15; 30; 60; 120; 360; 720; 1440 minutos, contando o número de lagartas que se alimentavam nas cultivares e, ao término do experimento, quantificou-se a área foliar consumida por cultivar. No teste de antibiose, além da identificação de cultivares de amendoim resistentes a S. frugiperda, determinaram-se, também, os graus de resistência através da análise multivariada. As cultivares foram semeadas em campo. Lagartas de primeiro ínstar foram individualizadas em placas de Petri forradas com papel filtro umedecido. Diariamente, foram fornecidos folíolos novos. Avaliaram-se... / This study aimed to evaluate possible sources of resistance of peanut cultivars of the upright growth and runner growth habit, to Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) by non-oviposition and non-feeding preference (tests choice and no-choice) and antibiosis. The experiments were conducted in laboratory under controlled conditions of temperature (25 ± 2°C), humidity (60 ± 10%) and photophase (12 hours). Peanut cultivars of upright growth habit (IAC 5, IAC 8112, IAC 22 and IAC Tatu ST) and runner growth habit (IAC 503, IAC 505, IAC 147, IAC 125, IAC Caiapó and IAC Runner 886) were evaluated. These cultivars were evaluated separately due to the material growth habit in all tests. Tests of non-oviposition preference were conducted with newly emerged adults, and they were fed with a 10% honey solution, remaining in the cages for four days until the start of evaluations. Evaluations consisted of quantifying the eggs and egg masses numbers, followed by calculation the number of eggs per egg masses. To perform non-feeding preference tests, leaves discs from different cultivars were placed in disposable Petri dishes followed by releasing of a third instar caterpillar for each cultivar. The attractiveness at 1; 5; 10; 15; 30; 60; 120; 360; 720 and 1,440 minutes was evaluated by counting the caterpillars number which were fed on cultivars, quantified the leaf area consumed by cultivar was evaluated at the end of the experiment. Additionally, identification of peanuts cultivars resistance to S. frugiperda, and the resistance degree was evaluated by multivariate analysis of the antibiosis test. The cultivars were planted in plots on the field. First instar larvae were placed individually in disposable Petri dishes plates, over a moistened filter paper. New leaflets were provided every day. The duration (days), weight (mg) and viability... (Complete abstract click electronic access below)

Resumo: O amendoinzeiro (Arachis hypogaea L.) tem o tripes do prateamento Enneothrips flavens como praga limitante à sua produção. O controle desse inseto atualmente é realizado com inseticidas convencionais, entretanto, a integração de táticas de controle poderá proporcionar uma solução mais estável e duradoura para o controle desta praga na cultura. Este trabalho teve por objetivo estudar o efeito de cultivares, espaçamentos e modos de aplicação de inseticidas sobre o tripes do prateamento E. flavens e seus reflexos na produção do amendoinzeiro. Os experimentos foram conduzidos na Fazenda de Ensino, Pesquisa e Extensão - FEPE/UNESP, localizada no município de Selvíria-MS. O primeiro experimento foi instalado na época da seca com semeadura realizada em 17/02/2004, no delineamento em blocos casualizados, com parcelas subdivididas, num esquema fatorial 2x2x4 representado por espaçamentos (0,70 e 0,90 m entre linhas), cultivares de crescimento rasteiro (IAC-Caiapó e Tégua) e modos de aplicação de inseticidas (1- granulado no solo + 8 pulverizações foliares; 2- tratamento de sementes; 3- 9 pulverizações foliares e 4- testemunha, sem controle). O segundo experimento foi instalado na época das águas com semeadura em 23/11/2004, no delineamento em blocos casualizados, com parcelas subdivididas, num esquema fatorial 2x2x3 representado por espaçamentos (0,70 e 0,90 m entre linhas), cultivares de crescimento rasteiro (IAC-Caiapó e IAC-886) e modos de aplicação de inseticidas (1-tratamento de sementes + 5 pulverizações foliares; 2- 6 pulverizações foliares e 3- testemunha, sem controle). Nas avaliações foram realizadas contagens de adultos e de ninfas do tripes em 10 folíolos fechados ou semi-abertos por parcela; para avaliar os sintomas de injúrias causadas pelos tripes no limbo foliar, utilizou-se uma escala visual de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The peanut (Arachis hypogaea L.) has the silvery thrips Enneothrips flavens as the limiting pest of yield. Nowadays, the control of this insect is accomplished with conventional insecticides, however the integration of control taticals will be able to provide a stable and lasting solution for the control of this pest in the culture. This work has the goal of studying the effect of cultivars, spacings and insecticides application manners on the population of silvery thrips E. flavens, and its reflexes on yield. The experiments were conducted in the Fazenda de Ensino, Pesquisa e Extensão - FEPE/UNESP, located in the Selvíria-MS. The first experiment was installed at that time of the drought with sowing accomplished in 17/02/2004, in the design in randomized blocks, with subdivided plots, in the factorial outline 2x2x4 represented by spacings (0,70 and 0,90 m between lines), groundnut growth cultivars (IACCaiapó and Tégua) and insecticides application manners (1- granulated in the soil + 8 leaf insecticide applications; 2- seeds treatment; 3- 9 leaf insecticide applications and 4-control, without control). The second experiment was installed at the time of waters with sowing accomplished in 23/11/2004, in the design in randomized blocks, with subdivided plots, in the factorial outline 2x2x3 represented by spacings (0,70 and 0,90 m between lines), groundnut growth cultivars (IAC-Caiapó and IAC-886) and insecticides application manners (1-seeds treatment + 5 leaf insecticide applications, 2- 6 leaf insecticide applications and 3-control, without control). In the evaluations, thrips adults and nymphs were counted in 10 leaflets closed or half-open for plots; to evaluate the injury symptoms caused by thrips in the leaf blade it was used visual scale of notes from 1 to 9. The peanut yield was evaluated in 4 m of the two central lines... (Complete abstract, access undermentioned electronic address) / Orientador: Alcebíades Ribeiro Campos / Coorientador: Valter Veriano Valério Filho / Coorientador: Edson Lazarini / Banca: Marco Eustaquio de Sa / Banca: Edson Luiz Lopes Baldin / Mestre

The bulk of Zimbabwe’s groundnut (Arachis hypogaea L.) crop is grown on sandy soils in the smallholder sector where sustainable production is hindered by acid soil infertility. The study goal was thus to examine the effects of soil acidity amelioration by four Ca-containing materials on nutrient composition, vegetative and reproductive growth, and quality of groundnut to formulate ameliorative strategies to improve productivity on acid soils. The effectiveness of calcitic lime (CL), dolomitic lime (DL), gypsum (G) and single superphosphate (SSP) in ameliorating soil acidity was determined in field experiments conducted for three seasons at two Research Stations in Zimbabwe, and in greenhouse experiments conducted for two seasons at Harare Research Station. In both experiments the lime application rates were from 0 to 4000 kg ha-1, while G application rates were from 0 to 3450 kg ha-1, and those of SSP were from 0 to 250 kg ha-1. Calcitic or dolomitic lime applied at 2000 or 4000 kg ha-1 increased soil pH and Ca and Mg contents in the pod and root zones, and in the plant material. Gypsum and SSP applications at 200 and 250 kg ha-1 respectively, had no significant effects on pH, Ca and Mg levels, but when applied in equivalent amounts of Ca as lime, gypsum improved soil Ca status. Effects of the four ameliorants on the N, P and K levels in the soils and in plant material were generally neither significant nor consistent. The direct and residual benefits of application of CL or DL were manifested in improved plant stands, better growth, nodulation, productivity and quality of groundnut. Gypsum applied at equal Ca rates as CL or DL was the superior Ca-source in improving pod and kernel quality. By the end of the third season, the increases in cumulative kernel yields due to application of 4000 kg ha-1 lime over non-application were up to 319%. The major growth-limiting factors on the studied acid soils were identified as deficiencies of Ca and Mg, and low pH per se. In a field experiment conducted to evaluate the tolerance of 15 groundnut genotypes to soil acidity, significant differences in yield and nutrient utilization efficiency of the genotypes were observed, implying that productivity on acid soils can be increased by growing genotypes efficient in uptake and utilization of nutrients. Results from greenhouse and growth chamber studies conducted to examine the effects of pH (3.0 - 7.0) and its interactions with Ca (0 - 2000 µM Ca) on early seedling growth and reproductive growth of groundnut indicated that low pH per se has a major detrimental impact on seedling survival, growth, pod formation, yield and quality of groundnut, but not on germination. The adverse effects of low pH were more pronounced in the absence of Ca, and became progressively less as the solution Ca concentrations increased. Further experiments showed that it is feasible to mitigate the adverse effects of soil acidity on groundnut germination and seedling survival by pelleting seeds with small amounts of CaCO3, or priming with CaSO4. / Dissertation (PhD (Plant Production: Agronomy))--University of Pretoria, 2003. / Plant Production and Soil Science / unrestricted