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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.
11

Cultivares de algodoeiro herbÃceo submetidas à infestaÃÃo natural de pragas / To cultivate of herbaceous cotton plant submitted to the natural infestation of plagues

Roselayne Ferro Furtado 17 March 2006 (has links)
As cultivares de algodoeiro apresentam caracterÃsticas morfolÃgicas e quÃmicas diferentes que podem influenciar a susceptibilidade Ãs pragas. Neste contexto, esse trabalho teve o objetivo de comparar a suscetibilidade das cultivares de algodoeiro herbÃceo BRS Antares, BRS 201, BRS Facual, BRS IpÃ, BRS ITA 96 BRS Sucupira, CNPA 8H, CNPA ITA 90, CNPA Precoce 3 e DeltaOpal Ãs pragas agrÃcolas, nas condiÃÃes de Fortaleza, CE. No experimento em campo, o delineamento experimental utilizado foi o de blocos casualizados, com trÃs repetiÃÃes para as plantas submetidas à infestaÃÃo natural e uma repetiÃÃo para as plantas com controle da infestaÃÃo. Cada parcela constituiu-se de trÃs linhas de trÃs metros, sendo a Ãrea Ãtil composta somente da linha central constituÃda por treze plantas. Para o monitoramento das pragas fez-se a cada sete dias observaÃÃes em campo. Na InfestaÃÃo por cochonilha (Planococcus sp.) e pulgÃo (Aphis gossypii) anotou-se o nÃmero de plantas infestadas quando essas apresentavam pelo menos uma colÃnia da espÃcie. Para o ataque de besouro-creme (Costalimaita ferruginea) anotou-se o nÃmero de plantas que apresentavam dano ≥ 10% do nÃmero total de folhas. Na infestaÃÃo por lagarta-rosada (Pectinophora gossypiella) anotou-se o nÃmero de plantas atacadas. Foram consideradas as seguintes caracterÃsticas agronÃmicas: (a) altura de inserÃÃo do primeiro ramo frutÃfero, (b) nÃmero de nÃs atà o primeiro ramo frutÃfero, (c) altura de plantas, (d) nÃmero de ramos frutÃferos por planta, (e) nÃmero de capulhos por planta, (f) dias para abertura da primeira flor, (g) dias para abertura do primeiro capulho, (h) peso mÃdio do capulho, (i) percentagem de fibra, (j) peso de 100 sementes, (l) precocidade da colheita e (m) produÃÃo. No experimento de casa-de-vegetaÃÃo, plantas das dez cultivares foram infestadas apÃs dezesseis dias de germinaÃÃo com cinco pulgÃes adultos. A contagem do nÃmero de adultos/planta foi realizada apÃs vinte e quatro horas de infestaÃÃo e a segunda avaliaÃÃo referente ao nÃmero de ninfas e de adultos/planta foi feita decorridos seis dias da instalaÃÃo do experimento. O delineamento experimental utilizado foi o inteiramente casualizado com dez tratamentos e seis repetiÃÃes. As pragas cochonilha, pulgÃo e besouro-creme nÃo demonstraram diferenÃa na preferÃncia das cultivares. A infestaÃÃo pela lagarta-rosada foi maior nas cultivares: BRS Antares, CNPA Precoce 3 e DeltaOpal. Foram encontradas reduÃÃes significativas em relaÃÃo ao controle para as seguintes caracterÃsticas: altura de inserÃÃo do primeiro ramo frutÃfero, altura das plantas, produÃÃo, precocidade e peso mÃdio dos capulhos. Considerando a infestaÃÃo das pragas e o rendimento de fibra na produÃÃo total entre as plantas infestadas, verificou-se que a cultivar CNPA Precoce 3 e CNPA ITA 90 apresentaram valores inferior e superior Ãs outras cultivares, respectivamente. Na infestaÃÃo artificial feita com os pulgÃes, nÃo houve diferenÃa significativa entre as cultivares, as quais apresentaram em mÃdia 4,06 adultos apÃs 24 horas de infestaÃÃo, 7,76 e 62,91 ninfas e adultos apÃs seis dias de infestaÃÃo, respectivamente. Pode-se concluir que a CNPA ITA 90 foi a cultivar com melhor desempenho nesta pesquisa em frente à susceptibilidade Ãs pragas. / The cotton cultivars have different morphological and chemical characteristics that may influence the susceptibility of the plants to pests. The objective of this work was to compare the susceptibility of the Upland cotton cultivars BRS Antares, BRS 201, BRS Facual, BRS IpÃ, BRS ITA 96, BRS Sucupira, CNPA 8 H, CNPA ITA 90, CNPA Precoce 3 and DeltaOpal to agricultural pests in the conditions of Fortaleza-CearÃ, Brazil. In field tests, the experimental design was a completely randomized block with three replications for the plants submitted to natural infestation and one repetition for the plants with control of the infestation. Each experimental unit had three rows with three meters long. The area observation was composed by the central row with thirteen plants. The evaluations of the infestations were made across observations in the field ever each seven days. The number of plants infested by mealybug (Planococcus sp.) and aphid (Aphis gossypii) was recorded each seven days when the plants had at least one colony of the species. The number of plants infested by yellow beetle (Costalimaita ferruginea) was recorded when the plants had at least 10% or more leaves damaged. In the infestation for pink bollworm (Pectinophora gossypiella) it was recorded the number of attacked plants. The following agronomic characteristics were considered: (a) first fruiting branch height, (b) number of nodes for the first fruiting branch, (c) plant height, (d) number of fruiting branches/plant, (e) number of boll/plant, (f) days of first flower open, (g) days of first boll open, (h) average of boll weight, (i) fiber percentage, (j) 100 seeds weight, (l) earliness and (m) yield. In greenhouse test, the plants of the ten cultivars were infested with six adult aphids after six days of germination. The number of adults/plant was recorded twenty four hours after infestation and the number of ninphs and adults/plant was also recorded six days after beginning of the experiment. The experimental design was a completely randomized with six replication of each cultivar. There were no significant differences among the cultivars damaged by Planococcus sp, A. gossypii, C. ferruginea. The cultivars BRS Antares, CNPA Precoce 3 and DeltaOpal were more infested by P. gossypiella than the other cultivars. There were significant differences among infested plants and control plants for the following characters: first fruiting branch height, plant height, earliness, yield and average of boll weight. CNPA Precoce 3 yielded less fibers and CNPA ITA 90 had the highest fiber yield. The greenhouse results indicated that there were no significant differences among the cultivars which showed an average of 4,06 adults twenty four hours after infestation and also 7,76 and 62,91 ninphs and adults respectively, six days after the infestation. CNPA ITA 90 cultivar was the one with smaller susceptibility to pests.
12

Adubação potássica via solo e foliar na produção e qualidade da fibra do algodoeiro / Potassium fertilization in soil and leaves aplications on the yield and technological quality of cotton fibers

FREITAS, Roberto José de 15 August 2006 (has links)
Made available in DSpace on 2014-07-29T16:24:13Z (GMT). No. of bitstreams: 1 Dissertacao Roberto J Freitas.pdf: 239807 bytes, checksum: 4ec206d2fecf55f55df3562fc5e07bbb (MD5) Previous issue date: 2006-08-15 / Cotton as a crop in Brazil has undergone significant changes in production technology and geographical location in recent years. Cultivation has shifted from traditional producing zones in the southeast of Brazil and the south region of the State of Goiás to the cerrados of the country's central-western region and the western part of Bahia. These technological changes were triggered by the adoption of exotic cultivars (American and Australian), with higher yield potential, better fiber quality, but also greater nutritional requirements. During this process, more demanding cultivars were consequently adopted, concurrently with the occupation of soils of lower natural fertility. During this period, a productivity increase in excess of 100% was verified. The conjunction of these factors has disorganized the fertilization recommendation practices adopted for this crop, since they were no longer adequately supported by the existing calibrations, generated under different soil conditions and at a different technological level. The use of fertilizers was then greatly intensified, in a most disorderly manner. Within this context, potassium was the nutrient whose use increased the most, due to the specific characteristics of this nutrient on the plant's metabolism and to its high degree of absorption by cotton plants. The potassium fertilization of cotton in the cerrados has therefore been performed in the various producing areas with great variation in rates and application modes, from total applications in the soil at pre-planting, to split applications in the soil, to supplementary foliar applications, still without the proper support from current experimental results. In this work, we evaluated the effect of combined soil and foliar applications of potassium on the productivity and quality of ginned cotton, under the cerrado conditions of the State of Goiás, by the installation of two experiments, combining different potassium rates in both application modes, organized in random blocks with split-plots. One assay was installed in Ipameri, with the application of five treatments to the soil (0, 60, 120, 180, and 240 kg ha-1 K2O ha-1) combined with four foliar treatments ( 0; 7.2; 14.4; and 21.6 kg K2O ha-1). Another assay was installed in Santa Helena de Goiás, in which four potassium levels were evaluated in the soil (0, 80, 160, and 240 kg K2O ha-1), combined with foliar rates similar to those used in the Ipameri assay. Significant productivity gains were observed for the soil applications in both assays, and for the foliar applications in the Ipameri assay. No interactions were observed between application modes. Also, no significant potassium fertilization effects were observed on the technological quality of the fiber. / A cultura do algodão no Brasil apresentou nos últimos anos significativas mudanças na tecnologia de produção e na localização geográfica. O cultivo deslocou-se de zonas produtoras tradicionais do Sudeste brasileiro e da região Sul do estado de Goiás, para os cerrados da região Centro Oeste e do Oeste da Bahia. As mudanças tecnológicas foram desencadeadas pela adoção de cultivares exóticos (americanos e australianos), com maior potencial produtivo, melhor qualidade de fibra e também maior exigência nutricional. Nesse processo ocorreu então a adoção de cultivares mais exigentes, concomitantemente à ocupação de solos de menor fertilidade natural. Verificou-se ainda nesse período incremento de produtividade superior a 100%. A conjunção desses fatores desorganizou a prática de recomendação de adubação na cultura, não mais amparada adequadamente pelas calibrações existentes, originadas em diferentes condições de solo e em outro nível tecnológico. Ocorreu então grande intensificação, de modo desordenado, na utilização de fertilizantes. O potássio nesse contexto foi o nutriente com maior incremento de utilização, devido às características específicas desse nutriente no metabolismo da planta e a seu alto nível de absorção pelo algodoeiro. A adubação potássica do algodoeiro nos cerrados, tem sido então efetuada nas diversas áreas produtoras, com grande variação nas doses e modos de aplicação, desde aplicações totais via solo em pré-plantio, aplicações via solo parceladas, até aplicações foliares complementares, ainda sem o devido respaldo de resultados experimentais contemporâneos. Esse trabalho avaliou nas condições do cerrado goiano, o efeito da combinação de aplicações de potássio via solo e foliar, na produtividade e qualidade da pluma do algodoeiro, através da instalação de dois experimentos, combinando diferentes doses de potássio nas duas modalidades de aplicação, arranjados em blocos ao acaso, com parcelas subdivididas. Foi instalado um ensaio em Ipameri com aplicação de cinco tratamentos via solo (0, 60, 120, 180 e 240 kg ha-1 de K2O) combinados a quatro tratamentos foliares ( 0; 7,2; 14,4 e 21,6 kg ha-1 de K2O). Outro ensaio foi instalado em Santa Helena de Goiás, onde foram avaliados quatro níveis de potássio via solo (0, 80, 160 e 240 kg ha-1 de K2O), combinados à doses foliares similares às do ensaio de Ipameri. Observaram-se ganhos de produtividade significativos para as aplicações via solo nos dois ensaios, e para as aplicações foliares no ensaio de Ipameri, não tendo sido verificadas interações entre as modalidades de aplicação. Não foram também verificados efeitos significativos da adubação potássica na qualidade tecnológica da pluma.
13

Crescimento e desenvolvimento do algodoeiro em função de doses de silício e ácido salicílico / COTTON PLANT GROWTH AND DEVELOPMENT DUE TO SILICON AND ACID SALICYLIC DOSES

Farias, Angélica Torres Vilar de 17 August 2012 (has links)
Made available in DSpace on 2015-09-25T12:21:28Z (GMT). No. of bitstreams: 1 PDF - Angelica Torres Vilar de Farias Parte 1.pdf: 3084992 bytes, checksum: c8267eaa6950355d73d478c31a92ef16 (MD5) Previous issue date: 2012-08-17 / The herbaceous cotton (Gossypium hirsutum L. race Latifolium Hutch) is one of the top ten species domesticated by human beings. Its main product is the fiber that wears almost half of humanity. It is also a source of protein, the fifth oilseed of the world and the second of Brazil, and the third source of biodiesel in our country with excellent quality oil, which is very good for human consumption and for the production of biofuels, and good chemical stability. Among the limiting factors for the cotton plant development stands mineral nutrition considering that there is little information available for this cultivar about the use of silicon, as a beneficial element and also the use of new plant hormones, that is the case of salicylic acid, used isolated and in combination. The objective of this research to identify and quantify the isolated and in combination effects of these two products on growth and biochemical aspects of herbaceous cotton, cultivar BRS 8H, that is quite drought resistant and produces an average of excellent intrinsic quality fiber. The experiment was conducted in semi-controlled conditions (greenhouse) in Campina Grande, Paraiba, on the premises of Embrapa Algodão in 20 liters capacity vessels. It was used a completely randomized design with three replications and 16 treatments, in a 4 x 4 factorial analysis scheme, having as factor four silicon concentrations: 0; 40; 80 e 120 g L-1 and four salicylic acid concentrations: : 0; 5; 10 e 15 mM. It was measured several variables of growth, such as non-destructive analysis (leaf area, stem diameter and plant height) at various periods of the cycle of the plant besides dry weight, leaf area ratio, leaf weight ratio, specific leaf area and biochemical aspects (total chlorophyll content and peroxidase activity). The cotton plant cv. BRS 8H when grown under foliar application of silicon (SI), and salicylic acid (SA) isolated and in combination, showed significant changes in growth and biochemical aspects, which highlights the need for further research with larger amplitude range of these factors order to obtain more conclusive results for the tested variables. / O algodoeiro herbáceo (Gossypium hirsutum L. raça Latifolium Hutch.) é uma das dez principais espécies domesticadas pelo homem, seu produto principal é a fibra que veste quase metade da humanidade. É ainda fonte de proteína, a quinta oleaginosa do mundo e a segunda do Brasil, e a terceira fonte de biodiesel do nosso país, tendo um óleo de excelente qualidade, muito bom para a alimentação humana e para a produção de biocombustíveis, sendo de boa estabilidade química. Dentre os fatores limitantes para o desenvolvimento do algodoeiro destaca-se a nutrição mineral, tendo em vista que são poucas as informações disponíveis para esta cultivar sobre o uso do silício, como elemento benéfico e também o uso de novos hormônios de plantas, caso do ácido salicílico, utilizados isolados e em conjunto, objetivou-se com este trabalho de pesquisa verificar e quantificar os efeitos isolados e conjuntos destes dois produtos no crescimento e aspectos bioquímicos do algodoeiro herbáceo, cultivar BRS 8H, que é bem resistente a seca e produz fibra média de excelente qualidade intrínseca. O experimento foi conduzido em condições semicontroladas (casa de vegetação), em Campina Grande, PB, nas dependências da sede da Embrapa Algodão em vasos de 20 litros de capacidade. Foi utilizado o delineamento inteiramente casualizado, com três repetições e 16 tratamentos, em esquema de análise fatorial 4 x 4, sendo os fatores quatro concentrações de silício: 0; 40; 80 e 120 g L-1 e quatro concentrações de ácido salicílico: 0; 5; 10 e 15 mM. Foram medidas diversas variáveis do crescimento, tais como análise não destrutiva (área foliar, diâmetro do caule e altura de planta) em vários períodos do ciclo da planta, além de massa seca, razão de área foliar, razão de peso foliar, área foliar específica e aspectos bioquímicos (teor de clorofila total e atividade da peroxidase). O algodoeiro cv. BRS 8H quando cultivado sob a aplicação foliar do silício (SI) e do ácido salicílico (AS) isolados e conjuntamente, apresentou alterações significativas no crescimento e em aspectos bioquímicos, o que evidencia a necessidade do desenvolvimento de novas pesquisas com maior faixa de amplitude desses fatores para que se obtenham resultados mais conclusivos para as variáveis testadas.
14

La résistance du cotonnier Gossypium hirsutum à la bactériose causée par Xanthomonas campestris pathovar malvacearum : rôle du gène GhLOX1 dans la réaction hypersensible / Resistance of cotton plant Gossypium hirsutum to the bacterial blight caused by Xanthomonas campestris pathovar malvacearum : role of GhLOX1 gene in the hypersensitive reaction

Sayegh, Majd 12 November 2009 (has links)
La RH est une réaction de défense. L’interaction entre G.hirsutum et Xcm repose sur le concept gène-à-gène. L’infection du cultivar Réba B50 possédant les gènes R B2B3 par Xcm18 conduit à une RH associée à une activité LOX, responsable de la peroxydation des lipides, et à la transcription du GhLOX1. Premièrement, 6 génotypes de G.hirsutum contenant divers gènes R ont été retenus pour analyser la variabilité de la réponse LOX suite à l’infection par Xcm1, 18 ou 20. Notre étude a porté sur plusieurs critères, le phénotype, la perte en eau, l’activité LOX et la transcription du GhLOX1. Les résultats montrent une variabilité du phénotype RH en fonction des sources de résistances. Pour chaque type d’interaction incompatible, l’activité LOX et la transcription du GhLOX1 révèlent une augmentation significative corrélée à l’apparition des symptômes RH et à la diminution de la teneur en eau. La réponse LOX est conservée lors de la RH, quelle que soit la race de Xcm ou le génotype. Le GhLOX1 considère comme un marqueur moléculaire de la résistance spécifique du cotonnier à Xcm. Deuxièmement, le rôle du GhLOX1dans la mise en place de la RH en analysant sa fonction potentielle par surexpression. Des cotylédons ont été transformés avec la séquence codante GhLOX1 fusionnée au CaMV35S. Ces cotylédons transformés ont révélé (i) une activité LOX significativement supérieure à celle des cotylédons témoins montrant que le GhLOX1 code pour une protéine active et (ii) un phénotype sans modifications apparentes par rapport à celui des cotylédons non transformées, sauf dans certains contextes d’interactions cotonnier/Xcm où la surexpression de ce gène induit l’apparition de symptômes de type RH. L’effet de l’agro-infiltration sur l’expression de certains gènes pendant la transformation a révélé l’induction précoce et non spécifique de l’expression de gènes de défense. Ces travaux constituent une première étape dans l’analyse fonctionnelle du GhLOX1 dans la résistance spécifique du cotonnier à Xcm / The HR is a defense strategy. The interaction between G.hirsutum and Xcm is governed by the gene-for-gene concept. The infection of the cultivar Reba B50 that contains B2B3 R genes by race Xcm18 leads to a HR associated with a LOX activity response involved in peroxidation of lipids and with transcription of GhLOX1. First, 6 genotypes of G. hirsutum containing various R genes were tested to analyze the variability of the LOX response following the infection by Xcm1, 18 or 20. Several criteria were investigated including the phenotype, the water loss, the LOX activity and GhLOX1 transcription. The results showed variation in HR phenotype according to the tested R genes. For each type of the incompatible interaction, LOX activity and transcription of GhLOX1 were always significantly increased paralleled the apparition of the HR symptoms and the decrease in the water content. LOX response (enzymatic activity and GhLOX1 transcription) is associated with HR whatever the genotype of both Xcm races and cotton plant. Thus, the GhLOX1 consider as a molecular marker of the cotton specific resistance to Xcm. Second, the role of the GhLOX1 gene in the execution of the cotton HR to Xcm by analyzing its possible function by over-expression, the cotyledons were transformed with the GhLOX1 coding sequence fused to the CaMV35S. These transformed cotyledons revealed (i) a LOX activity significantly higher than that detected in the control, showing that the GhLOX1 encodes for an active protein and (ii) that the phenotype of these cotyledons was indistinguishable as compared to the non transformed cotyledons, except when the HR symptoms were induced in some GhLOX1-over-expressed cotyledons. The effect of agro-infiltration on expression of some plant genes during the transformation revealed early and nonspecific induction of the expression of defense genes. This work constitutes a preliminary investigation for the functional analysis of the GhLOX1 in order to assess its role in the cotton specific resistance to Xcm
15

Predição não destrutiva de propriedades físicas e química em fibras de algodão naturalmente colorido / Non destructive prediction of physical and chemical proprieties in naturally colored cotton fiber

Silva, Demetrius José da 24 February 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-09T13:08:05Z No. of bitstreams: 1 PDF - Demetrius José da Silva.pdf: 1875869 bytes, checksum: 1061e2217a110ec6fb9511ee004c9cde (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T21:00:30Z (GMT) No. of bitstreams: 1 PDF - Demetrius José da Silva.pdf: 1875869 bytes, checksum: 1061e2217a110ec6fb9511ee004c9cde (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T21:00:39Z (GMT) No. of bitstreams: 1 PDF - Demetrius José da Silva.pdf: 1875869 bytes, checksum: 1061e2217a110ec6fb9511ee004c9cde (MD5) / Made available in DSpace on 2016-07-21T21:00:39Z (GMT). No. of bitstreams: 1 PDF - Demetrius José da Silva.pdf: 1875869 bytes, checksum: 1061e2217a110ec6fb9511ee004c9cde (MD5) Previous issue date: 2014-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The analyzes of the physical properties of cotton fibers are made in HVI, which is characterized by the high cost of acquisition and maintenance, performs invasive analysis and can’t be used to evaluate chemical characteristics of the samples. The classical methods for analysis of cotton fibers are destructive, time consuming, laborious and require large amounts of reagents. The VIS and NIR spectroscopy appears as a good alternative for the analysis of white and naturally colored cotton fiber because this method maintains the integrity of the sample, can perform multiple measurements simultaneously and has a relatively low cost of acquisition if compared to HVI. This work aims to obtain calibration models for the prediction of physical properties of naturally colored cotton fiber using spectroscopy in the visible (VIS) and near-infrared (NIR) spectra, combined with multivariate analysis. A set of 72 independent fiber samples of six cotton cultivars were used, 24 of them of two with white fiber cultivars (BRS Aroeira and BRS 8H) and four with naturally colored fiber (BRS Topázio, BRS Verde, BRS Safira, and BRS Rubi) were analyzed. The samples were analyzed for fiber yield (FIB), upper half mean length (UHM), uniformity index (UNF), short fiber index (SFI), strength (STR), elongation (ELG), micronaire (MIC), maturity (MAT), count strength product (CSP) and wax content (WAX). A Tukey’s test and principal component analysis (PCA) were performed in the reference results. The reflectance spectra were preprocessed (Savitzky-Golay, MSC and SNV) before a partial least squares regression (PLS) calibration method and then obtained within a spectral range of 400-2500 nm. The Tukey’s test and PCA results were statiscally significative for SFI, ELG and WAX (this last one is more specifically for BRS Verde) parameters to all analyzed cultivars but BRS Topázio. The STR, UHM and CSP measurements stand out for the white fiber cultivars and have a negative relationship as compared to the MIC, MAT and FIB variables. In the set of evaluatedsamples, the SFI, ELG and WAX measurements tend to provide an inverse correlation with theother variables analyzed. The results of these measurements using HVI system, for white andnaturally colored fiber, are dependent of the composition and the wax content of the the fiber.The PLS calibration models with pre-processed spectra used for analysis of the principal properties which express cotton fiber quality were consistent with results obtained in the HVI system. The application of VIS-NIR spectroscopy and PLS calibration are strategies that providesatisfactory results for the analysis of cotton fiber with speed, accuracy and reliability. / As análises das propriedades físicas das fibras de algodão são feitas em sistema HVI, que se caracteriza pelo alto custo de aquisição e manutenção, realiza análises invasivas e não pode ser usado para avaliação de características químicas das amostras. Já os métodos clássicos para análise de fibras de algodão são destrutivos, demorados, laboriosos e exigem grandes quantidades de reagentes. A espectroscopia VIS-NIR surge como uma boa alternativa para a análise de fibras de algodão branco e naturalmente colorido, pois se trata de um método que mantem a integridade da amostra, permite várias determinações simultaneamente e tem um custo de aquisição relativamente baixo se comparado ao HVI. Pelo exposto, objetivou-se obter modelos de calibração para a predição de atributos da fibra de algodão naturalmente colorido utilizando espectroscopia na região do visível (VIS) e infravermelho próximo (NIR), aliadas a técnicas de análise multivariada. Um conjunto de 72 amostras independentes de seis cultivares de algodão foi utilizado, sendo 24 delas de duas cultivares de fibra branca (BRS 8H e BRS Aroeira) e 48 amostras de quatro cultivares de fibra naturalmente colorida (BRS Topázio, BRS Verde, BRS Safira e BRS Rubi). As amostras foram analisadas para as propriedades de rendimento de fibra (FIB), comprimento médio (UHM), uniformidade (UNF), índice de fibras curtas (SFI), resistência (STR), alongamento à ruptura (ELG), micronaire (MIC), maturidade (MAT), índice de fiabilidade (CSP) e teor de cera (WAX). Os resultados de referência foram submetidos ao Teste de Tukey e análise de componentes principais (PCA). Os espectros de reflectância foram obtidos na faixa espectral de 400 a 2500 nm, os quais foram pré-processados (Savitzky-Golay, MSC e SNV) antes da calibração pelo método de regressão por Mínimos Quadrados Parciais (PLS). Constatou-se significância entre as variáveis SFI, ELG e WAX, as duas primeiras para as cultivares de fibra naturalmente coloridas, com exceção da BRS Topázio, e a última para a cultivar BRS Verde. As medidas de STR, UHM e CSP destacam-se para as cultivares de fibra branca e possuem relação negativa entre as variáveis MIC, MAT e FIB. No conjunto de amostras avaliadas, as medidas de SFI, ELG e WAX tendem a fornecer correlação inversa com as demais varáveis analisadas. Os resultados dessas medidas em sistema HVI, tanto em fibra branca e naturalmente colorida, são dependentes da composição da fibra para os teores de cera. Os modelos de calibração por PLS, em espectros pré-processados, para as principais propriedades que expressam a qualidade de fibras de algodão foram compatíveis com os resultados obtidos em sistema HVI. A aplicação da espectroscopia VIS-NIR e calibração por PLS são estratégias que fornecem resultados satisfatórios para análise de fibra de algodão com rapidez, precisão e confiabilidade.
16

Mecanismos morfofisiológicos da resistência de raças primitivas de algodoeiro ao bicudo

Carvalho, Thiele da Silva 29 February 2016 (has links)
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No. of bitstreams: 1 PDF - Thiele da Silva Carvalho.pdf: 511949 bytes, checksum: 0f4ebd9e36dd151268ce66e48942d5d7 (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The cotton boll weevil, Anthonomusgrandis Boheman (Coleoptera: Curculionidae), is a very important pest for the Brazilian cotton due to the injuries caused on the squares, flowers and bolls. These injuries reduce the production and are responsible for causing great economic losses to the farmer. Among the alternatives for the management of this pest can highlight the control tactics based on plant resistance to insects. This research aimed to determine the morphophysiological mechanism involved in resistance of some primitive races of cotton against boll weevil. The work were conducted in the field, in an area infested by the bolls weevils, in the greenhouse and in the laboratory of Pathology and Molecular Biology of Insects at EmbrapaCotton, municipality of Campina Grande, state of Paraíba. Two experiments were conducted. The first experiment aimed to select the most promising lines for resistance to boll weevil among the lines TB 15, TB 41, TB 75, TB 80, TB 85, TB 87, TB 90, TB 91 originating fromprimitive races of cotton and BRS 187 8H (control).The experimental design was randomized blocks with nine treatments and 4 repetitions. The treatments were represented by lines and cultivar cited cotton. Data were submitted to analysis of variance a nd the means compared by Tukey test at 5% probability. Pearson correlation coefficients were estimated between the number of punctured squares to feed and oviposition by the boll weevil and the 2 average number of trichomes and gossypol glands per cm leaf, height and diameter of the cotton rods with 120 days old. The second experiment aimed at determining the preference for feeding and oviposition of boll weevil on the squares of the six most promising lines selected in the first experiment in test with and without chance of choice.In the choice test was used completely randomized design in a factorial scheme with six cotton lines (G1=TB 90, G2= TB87, G3= TB 80; G4= TB 75; G5= TB 41 and G6= Grandless) nine hours evaluation (15 min, 30 min, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 12 hours and 24 hours) and ten replicates. In the test no choice, the experimental design was completely randomized, with five treatments, represented by boll weevil adults fed with cotton squares of the same lines of cotton used in the test of choice except to cultivate Grandless and five replications.The average number of trichomes and 2 2 gossypol glands per cm and teeth on bracts and the gossypol glands per cm on the sepals and of the nectaries in squares of cotton lines was determined to establish a correlation with the damage caused by feeding and oviposition of boll weevil on the squares. Data from tests with and without choice were subjected to analysis of variance (ANOVA) at 5% probability and the averages compared by Tukey test at 5% probability.In the field,the less preferred cotton line for ovipositionwasTB80. In the test-choice, the cottonlinewith smaller number of the boll weevil and punctured squares by feedingwasTB41. Under no chance of choice, the cultivarsTB80andTB41 wereless preferredfor food and line TB90showedsmaller number of punctured squares by oviposition.TheMorphophysiologicalmechanismsofresistanceprimitive racetested againstthe boll weevilare related tominor amounts of glands of the gossypol andnectariespresent, respectively, in the leaves and at the base of square. / O bicudo, AnthonomusgrandisBoheman (Coleoptera: Curculionidae), é uma praga de grande importância para a cotonicultura brasileira em função das injúrias provocadas sobre os botões florais, flores e maçãs do algodoeiro. Entre as alternativas para o manejo dessa praga pode-se destacar a tática de controle baseada na resistência de plantas aos insetos. Objetivou -se determinar o mecanismo morfofisiológico envolvido na resistência de algumas raças primitiva s de algodão ao bicudo. Foram realizados dois experimentos. O primeiro experimento visou selecionar as linhagens mais promissoras quanto à resistência ao bicudo entre as linhagens TB15, TB41, TB75, TB80, TB85, TB87, TB90, TB91 oriundas de raças primitivas de algodoeiros e a cultivar BRS 187 8H (testemunha). O delineamento experimental foi em blocos ao acaso, com nove tratamentos e 4 repetições. Os tratamentos foram representados pelas linhagens e a cultivar de algodoeiros citadas. O segundo experimento visou determinar a preferência para alimentação e oviposição do bicudo sobre os botões florais das seis linhagens mais promissoras selecionadas no primeiro experimento em teste com e sem chance de escolha. No teste com escolha, utilizou - se delineamento experimental inteiramente casualizado, em esquema fatorial com seis linhagens de algodoeiro (G1= TB90; G2= TB87; G3= TB80; G4= TB75; G5 = TB41 e G6= Grandless), nove horários de avaliação (15 min, 30 min, 1 hora, 2horas, 4 horas, 6 horas, 8 horas, 12 horas e 24 horas) e dez repetições. No teste sem chance de escolha, o delineamento experimental foi inteiramente casualizado, com cinco tratamentos, representados por adultos do bicudo alimentados com botões florais das mesmas linhagens de algodoeiros utilizadas no te ste de escolha, exceto a cultivar Grandless e cinco repetições.Os dados de ambos os experimentos foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey(P=0,05), utilizando-se o Sistema de Análises Estatíssticas e Genéticas (SAEG) da Universidade Federal de Viçosa. Foram estimados no experimento de seleção de linhagens de algodoeiros resistentes ao bicudo, os coeficientes de correlação de Pearson entre o número de botões florais com orifício de alimentação e oviposição pelo bicudo e os números médios de tricomas e de glândulas de 2 gossipol por cm das folhas e altura e diâmetro das hastes das plantas de algodoeiro com 120 dias de idade. No ensaio de preferência de alimentação e oviposição do bicudo foram estimados os coeficientes de correlação de Pearson entre o número de botões florais com orifício de alimentação e oviposição pelo bicudo e os números médios de tricomas e de glândulas de 2 2 gossipolpor cm e dos dentes nas brácteas, de glândulas de gossipol por cm nas sépalas e o de nectários nos botões florais das linhagens de algodoeiros.No campo, a linhagem de algodoeiro menos preferida para oviposição foi TB80. No teste de chance de escolha, a linhagem de algodoeiro com menor número de bicudos e de orifícios de alimentação foi TB41. Sob condições de confinamento, as cultivares TB80 e TB41 foram menos preferidas para alimentação enquanto que a linhagem TB90 apresentou menor número de orifícios de oviposição. Os mecanismos morfofisiológicos de resistência de raças primitivas testadas contra o bicudo estão relacionados às menoresquantidades de glândulas de gossipole de nectários presentes, respectivamente, nas folhas e na base dos botões florais.
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Screening upland cotton for resistance to cotton fleahopper (Heteroptera: Miridae)

Mekala, Diwakar Karthik 15 November 2004 (has links)
Cotton (Gossypium hirsutum L.) crop maturity is delayed by cotton fleahopper (Pseudatomoscelis seriatus Reuter) (fleahopper) feeding on early-season fruit forms which increases vulnerability to late-season pests such as Helicoverpa zea (Boddie) and Heliothis virescens (Fabricius). The objectives of this research were to evaluate methods of screening for resistance to fleahopper and to screen selected genotypes. Six fleahoppers were caged on plants in the insectary for 72 h. Numbers of live fleahoppers and percent square damage were determined 48 h following the removal of fleahoppers. Fleahopper numbers and percent square set were determined on randomly selected plants of 16 genotypes when grown under field conditions in 2002 and 2003. Across multiple sampling dates, the number of fleahoppers per plant was higher (p=0.05) in G. arboreum and Pilose (G. hirsutum), but no consistent differences were observed among the remaining 15 genotypes which represented several germplasm pools across the United States. Field and no-choice feeding tests suggested that Pilose, Lankart 142, Suregrow 747, and Stoneville 474 were more resistant hairy-leaf genotypes and not different (p=0.05) in resistance than the smooth-leaf genotypes, Deltapine 50 and TAM 96WD-69s. Pin-head, match-head, and one-third grown squares were removed from plants and placed on agar in petri-plates. Four fleahoppers were released per plate and allowed to feed for 48 h. Fleahopper damage, brown areas along the anthers and/or brown and shrunken pollen sacs was most evident in pin-head sized squares.
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Screening upland cotton for resistance to cotton fleahopper (Heteroptera: Miridae)

Mekala, Diwakar Karthik 15 November 2004 (has links)
Cotton (Gossypium hirsutum L.) crop maturity is delayed by cotton fleahopper (Pseudatomoscelis seriatus Reuter) (fleahopper) feeding on early-season fruit forms which increases vulnerability to late-season pests such as Helicoverpa zea (Boddie) and Heliothis virescens (Fabricius). The objectives of this research were to evaluate methods of screening for resistance to fleahopper and to screen selected genotypes. Six fleahoppers were caged on plants in the insectary for 72 h. Numbers of live fleahoppers and percent square damage were determined 48 h following the removal of fleahoppers. Fleahopper numbers and percent square set were determined on randomly selected plants of 16 genotypes when grown under field conditions in 2002 and 2003. Across multiple sampling dates, the number of fleahoppers per plant was higher (p=0.05) in G. arboreum and Pilose (G. hirsutum), but no consistent differences were observed among the remaining 15 genotypes which represented several germplasm pools across the United States. Field and no-choice feeding tests suggested that Pilose, Lankart 142, Suregrow 747, and Stoneville 474 were more resistant hairy-leaf genotypes and not different (p=0.05) in resistance than the smooth-leaf genotypes, Deltapine 50 and TAM 96WD-69s. Pin-head, match-head, and one-third grown squares were removed from plants and placed on agar in petri-plates. Four fleahoppers were released per plate and allowed to feed for 48 h. Fleahopper damage, brown areas along the anthers and/or brown and shrunken pollen sacs was most evident in pin-head sized squares.
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Identification of Root-knot Nematode Resistance Loci in Gossypium hirsutum Using Simple Sequence Repeats

Del Rio, Sonia Y 03 October 2013 (has links)
Gossypium hirsutum, upland cotton, is one of the major crops grown in the United States and the world. Upland cotton is cultivated in areas that are ideal breeding grounds for the difficult to manage, southern root-knot nematode (RKN), Meloidogyne incognita. Host plant resistance is the most effective way to control RKN populations. However, resistance used in most breeding programs stems from a few related sources. Novel sources of resistance have been identified but have yet to be introduced into elite breeding lines or genetically studied. The objectives of this study are two-fold. The first is to develop elite germplasm by introgressing RKN resistance from primitive accessions into modern cotton genotypes via backcrossing. The second is to use simple sequence repeats (SSRs) to identify loci associated with RKN resistance in the primitive accessions. The genotypes used will be: 1) inoculated with M. incognita, 2) phenotypically analyzed by measuring the nematode reproduction as eggs per gram of fresh root and host response using a root gall index, 3) genetically evaluated by using SSR markers to detect polymorphisms between the RKN resistant TX accessions and DP90 (susceptible genotype), and 4) analyzed using linkage and mapping software. Elite germplasm that contains: 1) high yield potential and a high level of RKN- resistance or 2) high fiber quality and RKN-resistance was developed by performing two backcrosses based on phenotypic analyses. A third screen is currently underway to ensure the introgression of the RKN resistance genes. Agronomic tests will need to be done before the germplasm is released. Genetic analyses using SSR-based primer sets of the TX accessions did not yield expected results. Of the 508 primers sets tested, only 31 were polymorphic between the TX accessions and DP90. A bulked segregant analysis approach was used to test the 31 primer sets on the resistant and susceptible bulks of the F2 population but no polymorphisms were seen. However, analyses found that the TX accessions were more genetically similar to Mexico Wild Jack Jones than to Clevewilt 6-3-5. More work needs to be done to understand the mechanism of RKN resistance in the TX accessions.
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Análise da tolerância à salinidade em plantas de sorgo, feijão-de-corda e algodão / Analysis of the salt tolerance in plants of sorgo, cowpea and cotton

Sousa, Carlos Henrique Carvalho de January 2007 (has links)
SOUSA, Carlos Henrique Carvalho de. Análise da tolerância à salinidade em plantas de sorgo, feijão-de-corda e algodão. 2007. 72 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-14T20:06:17Z No. of bitstreams: 1 2007_dis_chcsousa.pdf: 705339 bytes, checksum: f797f36e702e103594bf2a0452343980 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-06-14T20:37:55Z (GMT) No. of bitstreams: 1 2007_dis_chcsousa.pdf: 705339 bytes, checksum: f797f36e702e103594bf2a0452343980 (MD5) / Made available in DSpace on 2016-06-14T20:37:55Z (GMT). No. of bitstreams: 1 2007_dis_chcsousa.pdf: 705339 bytes, checksum: f797f36e702e103594bf2a0452343980 (MD5) Previous issue date: 2007 / The objective of this paper was to evaluate ions concentration and some morphophysiological parameters associates to the salt tolerance in sorghum, cowpea, and cotton plants. Plants were cultivated in plastic pots, using 15 kg of sand soil at greenhouse conditions and subjected to three different salt concentrations (0.5; 4.0; and 8.0 dS.m-1) in irrigation water. A completely randomized design, in a factorial arrangement 3 x 3 (3 species x 3 salt levels), with four replicates was adopted. During the experimental period, plant height and water use was measured. After 42 days of salt application they were measured the salinity of drained water and in the soil, total leaf area and dry masses of leaves, stems and roots. Leaf succulence, specific leaf mass, carbon partitioning and the concentrations of Na, Cl, K, Ca, and proline were also determined. The application of saline water affected the carbon partitioning, reduced plant growth and water use, and caused salt accumulation in drained water and into the soil. However, the percentage of ion extraction from the soil was low in the three species, being higher in cotton and lower in sorghum. The tolerance index, on the basis of the growth data, confirmed the highest sensibility of the cowpea and the highest tolerance of the cotton. The cotton showed some important difference to the other species, presenting greater accumulation and retention of Na and Cl in the roots, greater accumulation of these ions in the leaf blades, lower changes in K concentration and increase in proline contents in response to sat stress application. On the other hand, sorghum showed lower concentrations of potentially toxic ions (Na plus Cl) in the leaf blades. However, it also presented reductions in K and Ca contents, what can contribute to growth inhibition in this species. The high leaf Cl concentration, associated with the absence of the other protection mechanisms, contributed, at least in part, to higher sensibility of the cowpea to salt stress imposed. / O objetivo deste trabalho foi avaliar os teores e distribuição de íons e alguns parâmetros morfosiológicos associados com a tolerância à salinidade em plantas de sorgo, feijão-de-corda e algodão. As plantas foram cultivadas em vasos contendo 15 kg de areia lavada, em condições de casa-de-vegetação, e irrigadas com águas com três níveis de salinidade (0,5, 4,0 e 8,0 dS m-1). O experimento foi montado seguindo um delineamento inteiramente casualizado, com arranjo fatorial 3 x 3 (3 espécies x 3 níveis de salinidade), com quatro repetições. Durante a condução do experimento foram mensuradas a altura da planta e o consumo de água. Após 42 dias do início dos tratamentos foram medidas> acúmulo de sais na água drenada e no solo, a área foliar e a produção de matéria seca de folhas, caules e raízes. Foram também determinados: a suculência foliar, a massa específica foliar, a partição de carbono e os teores de Na+, Cl-, K+, Ca2+ e prolina. A aplicação de água salina afetou a partição de carbono, reduziu o crescimento e o consumo de água pelas plantas, e provocou acúmulo de sais na água drenada e no solo. No entanto, as percentagens de extração de sais foram baixas nas três espécies, sendo maior em algodoeiro e menor em sorgo A tolerância à salinidade foi avaliada através dos dados de crescimento, os quais confirmaram a maior sensibilidade do feijão-de-corda e a maior tolerância do algodão. O algodão se diferenciou das duas outras espécies por apresentar maior acúmulo e retenção de Na+ e Cl- nas raízes, maior acúmulo desses íons nos limbos foliares, menores alterações nos teores de K+ e aumento nos teores de prolina em resposta ao aumento da salinidade. O sorgo apresentou menores teores de íons potencialmente tóxicos (Na+ + Cl-) nos limbos foliares, porém, apresentou reduções nos teores de K+ e Ca2+ na parte aérea. O elevado acúmulo de Cl- nas folhas, associado à falta de outros mecanismos eficientes de proteção, contribuiu, pelo menos em parte, para a maior sensibilidade do feijão-de-corda ao estresse salino.

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