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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.
1

Assistência de ar e volumes de pulverização na deposição de gotas e controle do arroz vermelho (Oryza sativa L.)

Viganó, Leopoldo Luís de Souza [UNESP] 23 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-23Bitstream added on 2014-06-13T20:28:24Z : No. of bitstreams: 1 vigano_lls_me_botfca.pdf: 315511 bytes, checksum: 1c704179aaf952553a743ea80191f02c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve como objetivo avaliar o efeito da assistência de ar junto à barra de pulverização e três volumes de aplicação na dessecação e deposição da calda em arroz vermelho sob cultivo de nabo forrageiro em recuperação de áreas de várzeas, pulverizado com herbicida paraquat e corante azul brilhante, respectivamente. Os volumes de calda de pulverização foram 100, 200 e 300 L ha-1, da solução contendo corante alimentício (0,15%, p/v). Tanto na presença do ar junto à barra quanto na sua ausência foram utilizadas pontas de pulverização de jato plano tipo AXI 110015 a pressão de 117,3 kPa, AXI 11002 e AXI 11003 a pressão de 276 kPa. A avaliação da deposição da pulverização deu-se em folhas de plantas de arroz vermelho. Verificou-se nos resultados que houve diferença na deposição entre diferentes técnicas e volumes de calda testados nas plantas de arroz vermelho. Maior deposição foi alcançada pelo maior volume aplicado (300 L ha-1) com a assistência de ar junto à barra pulverizadora. Não se constatou diferença na deposição quando aplicados os volumes de 100, 200 e 300 L ha-1 sem assistência de ar e 200 e 300 L ha-1 com assistência de ar. As maiores porcentagens de dessecação de arroz vermelho foram constatadas com a aplicação de 300 L ha-1, tanto na presença quanto na ausência de assistência de ar junto à barra pulverizadora. / The aim of this research was to evaluate the effect of air-assistance on spraying at three volumes in the dessecation and deposition on red rice under fodder radish cultivation. To evaluate the dessecation and spray deposition were used paraquat herbicide and a Brilliant Blue dye, respectively. The three volumes of spray were 100, 200 and 300 L ha-1, using a tracer dye at 0,15% (w/v). Both solution used flat fan nozzles AXI 110015 at 117.3 kPa, AXI 11002 and AXI 11003 at 276 kPa. The evaluation of deposition was made on red rice leaves. We observed no significant different deposition between spray techniques and application volumes on red rice plants. Higher deposition was obtained by 300 L ha-1 application with air assistance in the spray boom. No difference it was observed on spray deposition at 100, 200 and 300 L ha-1 volumes without air assistance and at 200 as well as 300 L ha-1 with air assistance. The highest percentages of red rice dessecation were observed with 300 L ha-1 application with or without air assistance at the sleeve boom sprayer.
2

Genetic diversity and species relationships in the Oryza complex and glufosinate tolerance in rice

Vaughan, Laura Kelly 29 August 2005 (has links)
The weed red rice is a major problem in rice producing areas world wide. All of the red rice in commercial rice fields in the United States has traditionally been considered to be the same species as commercial rice, Oryza sativa. However, using DNA markers it was found that most of the red rice with black hulls was sufficiently divergent to be considered a separate species. This includes TX4, a red rice ecotype that has been reported to have considerable natural tolerance to the herbicide glufosinate. TX4 is closely related to samples that have been classified as Oryza rufipogon. However, it was shown that both the TX4-like red rice from commercial fields and most of the Oryza rufipogon accessions in the US National Small Grains Collection are more accurately classified as Oryza nivara. This is significant since Oryza rufipogon is regulated under the Federal Noxious Weed Act, while Oryza nivara is not. Oryza nivara closely related to TX4 was found to be widely distributed across the rice production areas of Texas and was also found in Arkansas, Louisiana, and Mississippi. Of 240 samples from across Texas, 23 samples from six different counties were identical with TX4 with all 18 DNA markers tested. The reported glufosinate tolerance of TX4 is a potential problem since this same herbicide would be used in conjunction with genetically modified (GM) that is being developed as a method of red rice control. Thus, field, greenhouse and tissue culture studies were conducted to evaluate the degree of glufosinate tolerance in TX4. TX4 typically was severely damaged by glufosinate, but not efficiently controlled. Even with the maximum number of herbicide applications at the proposed maximum label rate, TX4 often re-sprouted and produced viable seed. Herbicide tolerance was found to be variable, but appears to be sufficient to present a problem with the use of the GM glufosinate resistant varieties currently under development, particularly when combined with variation in the response of ??sensitive?? varieties.
3

Mechanisms facilitating and evolutionary consequences of gene flow in two crop-wild hybrid complexes sunflower and rice /

Reagon, Michael, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 114-129).
4

Chinese Red Rice-induced Myopathy

Smith, Dena J., Olive, Kenneth E. 01 December 2003 (has links)
A middle-aged man presented with joint pain and muscle weakness that had begun 2 months before presentation. Three months before presentation, he had begun to take the herbal preparation Chinese red rice. Laboratory testing revealed a moderately elevated creatine phosphokinase level. Symptoms and laboratory abnormalities resolved with discontinuation of the Chinese red rice. Eight months later, he resumed the product and his creatine phosphokinase level rose again. Lovastatin is a naturally occurring component of Chinese red rice and was the probable cause of his myopathy.
5

Características químicas, tecnológicas e sensoriais de extrusados expandidos a partir de arroz pigmentado / Chemical, technological and sensory characteristics of extrudates from pigmented rice.

Meza, Silvia Leticia Rivero 21 October 2015 (has links)
O arroz integral pigmentado (vermelho ou preto) (Oryza sativa, L.) é saudável. Ambos são nutritivos, possuem elevado teor de compostos bioativos, e apresentam características sensoriais diferenciadas ao arroz integral branco. O grande destaque sob o ponto de vista de composição química é o seu elevado teor de compostos fenólicos, associado à alta capacidade antioxidante. A demanda por arroz pigmentado ainda é reduzida, porém, existe uma tendência e o interesse em agregar valor a esses grãos, produzindo alimentos alternativos como flocos de arroz, cereais matinais e snacks. O objetivo deste estudo foi desenvolver produtos extrusados expandidos a partir de duas novas cultivares comerciais de arroz integral preto (SCS 120 ÔNIX) e vermelho (SCS 119 RUBI), provenientes da Epagri/SC. Na otimização do processo considerou-se as melhores propriedades tecnológicas e a retenção de compostos bioativos. Foi investigado o efeito do processo de extrusão nos fitoquímicos e sua atividade antioxidante, antes e após a extrusão. Além disso, a aceitabilidade de dois produtos finais foi realizada com 150 consumidores. O arroz preto apresentou teores significativamente maiores de macronutrientes (proteínas, fibras e minerais) do que o arroz vermelho. O teor de compostos fenólicos totais (CFT) e flavonoides no arroz preto foi de 25% (569,3 mg eq. ác. ferúlico/100g) e 44% (496,9 mg eq. catequina/100 g), respectivamente, superior ao do arroz vermelho. Os flavonoides são representados principalmente por antocianinas no arroz preto e por proantocianidinas no arroz vermelho. O arroz preto apresentou maior atividade antioxidante. A partir do delineamento composto central rotacional as condições ótimas de extrusão foram de 15,5 e 16% de umidade e de 159 e 150ºC de temperatura, para o arroz preto e vermelho, respectivamente. O processo de extrusão resultou em perdas drásticas de TPC, flavonoides, proantocianidinas e o conteúdo remanescente não foi maior que 14% no arroz vermelho e a atividade antioxidante residual também foi baixa. O arroz preto também foi afetado significativamente pela extrusão mas em menores proporções. A concentração após a extrusão foi de 32 % (TPC), 22% (flavonoides), 11% (antocianinas) e a atividade antioxidante remanescente de 40% e 30% pelos métodos de ORAC e DPPH, respectivamente. Quanto à análise sensorial, os extrusados obtidos de arroz preto e vermelho não tiveram diferença significativa na aceitação (p≤0,05). As notas médias atribuídas por 150 provadores para todos os atributos avaliados ficaram situadas no intervalo de 4,8 a 7,7 (correspondente as categorias \"nem gostei/nem desgostei\" a \"gostei muito\") da escala hedônica de 9 pontos. Altos valores de aceitabilidade (maiores que 70%) foram observados para formato, tamanho, cor e crocância no cereal seco e consistência no cereal com leite. A menor aceitabilidade (60%) foi notada no sabor. Isto pode ser explicado pela ausência de aromatizante e/ou edulcorante na formulação. Ainda, foi observado que 26% dos provadores certamente comprariam ambos os extrusados. A farinha de arroz pigmentado é uma alternativa para a elaboração de cereais matinais extrusados na qual apresentam coloração própria, boas características nutricionais e sensoriais, além de ser um produto isento de glúten. / Whole pigmented rice (black and red) (Oryza sativa, L.) is a healthy food. Both types present are nutritious and present high contents of bioactive components, and show distinguishing sensorial properties, unlike those found in whole white rice. However, the most noticeable difference regarding the chemical composition of black and red rice is their high content of phenolic compounds, associated to a high antioxidant activity. Consumption of pigmented rice is still low, but there is an increasing trend and interest in adding value to pigmented grains, producing alternative food products such as rice flakes, breakfast cereals and snacks. Then, the objective of this study was to produce extruded rice from whole grain of black (SCS 120 ÔNIX) and red rice (SCS 119 RUBI). Rice cultivars were grown at experimental fields of Epagri/SC. The conditions of the extrusion process were optimized to achieve the best technological properties and to attain the retention of bioactivties. The phytochemical composition antioxidant activity and technological properties of the pigmented rice flour were investigated before and after extrusion. In addition, the acceptability of the two selected final products was assessed by 150 consumers. The black rice showed significantly higher contents of macronutrients (protein, fiber and minerals) than red rice. The total phenolic compounds (TPC) and total flavonoids in black rice were also 25% (569.3 mg eq. ac. ferulic/100 g) and 44%, (496.9 mg eq. catechin/100 g) respectively, higher than in red rice. In black rice flavonoids were represented mainly by anthocyanins, while in red rice the main flavonoids were proanthocyanidins. Black rice showed the highest antioxidant activity. The predicted optimum extrusion conditions were settled down at 15.5 and 16 % of moisture and 159 and 150ºC of temperature for black and red rice, respectively. The extrusion process induced a drastic loss of TPC, flavonoids and proanthocyanidins and remaining contents were not higher than 14% in red rice and residual antioxidant activity was also very low. Black rice was also significantly affected by the extrusionm but in a lesser degree. The concentration after extrusion was 32% (TPC), 22 % (flavonoids), 11% (anthocyanins) and a remaining 40 % and 30 % antioxidant activity by ORAC and DPPH methods, respectively. Consumer acceptability of extrudates was similar and the average scores awarded were located between 4.8 to 7.7 (corresponding to the categories \"not liked/disliked to \"liked so much\") for all attributes evaluated in the 9-point hedonic scale. High acceptability scores (higher than 70 %) were observed for shape, size, color and texture hardness in dry extrudates and consistency in extrudates with milk. The lowest acceptability (60 %) was noted for flavor. It could be explained because of the extrudates were not flavoured. Furthermore, it was shown that 26 % of consumers certainly would buy both extrudates. The pigmented rice flour demonstrated to be a good alternative to produce extruded breakfast cereals which had his own color, showed good nutritional and sensory properties, besides being a gluten-free product.
6

Assistência de ar e volumes de pulverização na deposição de gotas e controle do arroz vermelho (Oryza sativa L.) /

Viganó, Leopoldo Luís de Souza, 1981- January 2006 (has links)
Orientador: Carlos Gilberto Raetano / Banca: Dagoberto Martins / Banca: Marcelo da Costa Ferreira / Resumo: O presente trabalho teve como objetivo avaliar o efeito da assistência de ar junto à barra de pulverização e três volumes de aplicação na dessecação e deposição da calda em arroz vermelho sob cultivo de nabo forrageiro em recuperação de áreas de várzeas, pulverizado com herbicida paraquat e corante azul brilhante, respectivamente. Os volumes de calda de pulverização foram 100, 200 e 300 L ha-1, da solução contendo corante alimentício (0,15%, p/v). Tanto na presença do ar junto à barra quanto na sua ausência foram utilizadas pontas de pulverização de jato plano tipo AXI 110015 a pressão de 117,3 kPa, AXI 11002 e AXI 11003 a pressão de 276 kPa. A avaliação da deposição da pulverização deu-se em folhas de plantas de arroz vermelho. Verificou-se nos resultados que houve diferença na deposição entre diferentes técnicas e volumes de calda testados nas plantas de arroz vermelho. Maior deposição foi alcançada pelo maior volume aplicado (300 L ha-1) com a assistência de ar junto à barra pulverizadora. Não se constatou diferença na deposição quando aplicados os volumes de 100, 200 e 300 L ha-1 sem assistência de ar e 200 e 300 L ha-1 com assistência de ar. As maiores porcentagens de dessecação de arroz vermelho foram constatadas com a aplicação de 300 L ha-1, tanto na presença quanto na ausência de assistência de ar junto à barra pulverizadora. / Abstract: The aim of this research was to evaluate the effect of air-assistance on spraying at three volumes in the dessecation and deposition on red rice under fodder radish cultivation. To evaluate the dessecation and spray deposition were used paraquat herbicide and a Brilliant Blue dye, respectively. The three volumes of spray were 100, 200 and 300 L ha-1, using a tracer dye at 0,15% (w/v). Both solution used flat fan nozzles AXI 110015 at 117.3 kPa, AXI 11002 and AXI 11003 at 276 kPa. The evaluation of deposition was made on red rice leaves. We observed no significant different deposition between spray techniques and application volumes on red rice plants. Higher deposition was obtained by 300 L ha-1 application with air assistance in the spray boom. No difference it was observed on spray deposition at 100, 200 and 300 L ha-1 volumes without air assistance and at 200 as well as 300 L ha-1 with air assistance. The highest percentages of red rice dessecation were observed with 300 L ha-1 application with or without air assistance at the sleeve boom sprayer. / Mestre
7

Red rice (Oryza sativa L.) ecotype tolerance to herbicides and winter weed management practices

Nanson, Weldon Duane 15 May 2009 (has links)
Studies were conducted in 2004, 2005, and 2006 in south Texas to evaluate fall, winter, and spring weed control for commercial rice production, study tillage intensity and herbicide rate interactions for rice production, and determine the tolerance of red rice ecotypes from Texas rice fields using selected herbicides at varying rates. A single application of any herbicide or combination of herbicides was not adequate for weed control throughout the fall, winter, and spring. Fall applications of clomazone plus flumioxazin provided consistent weed control. Addition of flumioxazin to glyphosate provided excellent winter annual grass control with winter application. A residual herbicide, coupled with the proper contact herbicide is the key to extending control. In 2006, all tillage by herbicide treatments in all studies provided ≥ 90% control of all weed species. The conventional tillage treatment with low herbicide input provided the highest rice grain yield in 2005 and 2006, though they were not significantly different from the spring stale seedbed program with medium or high herbicide input in 2006. In 2006, fall stale seedbed treatments were among the lowest in yield. A stale seedbed program may be useful, but with substantial weed pressure, increasing the intensity of herbicide applications is necessary to overcome the absence of tillage. All rice ecotypes were adequately controlled by glyphosate and only one ecotype was found to be tolerant to 2x rates of both imazethapyr and imazamox. All ecotypes were adequately controlled by 2x rates of more than two of the four herbicides which included imazethapy, imazamox, glufosinate, and glyphosate. Ecotypes from the 3.2 group, genetically similar to the ecotype TX4, appear to be the most likely to exhibit tolerance to a given herbicide. Tolerance to glufosinate was found in 70% of the group 3.2 ecotypes. Sixty percent of ecotypes from group 3.1, genetically similar to Oryza rufipogon were not adequately controlled by glufosinate.
8

Red rice (Oryza sativa L.) ecotype tolerance to herbicides and winter weed management practices

Nanson, Weldon Duane 15 May 2009 (has links)
Studies were conducted in 2004, 2005, and 2006 in south Texas to evaluate fall, winter, and spring weed control for commercial rice production, study tillage intensity and herbicide rate interactions for rice production, and determine the tolerance of red rice ecotypes from Texas rice fields using selected herbicides at varying rates. A single application of any herbicide or combination of herbicides was not adequate for weed control throughout the fall, winter, and spring. Fall applications of clomazone plus flumioxazin provided consistent weed control. Addition of flumioxazin to glyphosate provided excellent winter annual grass control with winter application. A residual herbicide, coupled with the proper contact herbicide is the key to extending control. In 2006, all tillage by herbicide treatments in all studies provided ≥ 90% control of all weed species. The conventional tillage treatment with low herbicide input provided the highest rice grain yield in 2005 and 2006, though they were not significantly different from the spring stale seedbed program with medium or high herbicide input in 2006. In 2006, fall stale seedbed treatments were among the lowest in yield. A stale seedbed program may be useful, but with substantial weed pressure, increasing the intensity of herbicide applications is necessary to overcome the absence of tillage. All rice ecotypes were adequately controlled by glyphosate and only one ecotype was found to be tolerant to 2x rates of both imazethapyr and imazamox. All ecotypes were adequately controlled by 2x rates of more than two of the four herbicides which included imazethapy, imazamox, glufosinate, and glyphosate. Ecotypes from the 3.2 group, genetically similar to the ecotype TX4, appear to be the most likely to exhibit tolerance to a given herbicide. Tolerance to glufosinate was found in 70% of the group 3.2 ecotypes. Sixty percent of ecotypes from group 3.1, genetically similar to Oryza rufipogon were not adequately controlled by glufosinate.
9

Imazethapyr: red rice control and resistance, and environmental fate

Avila, Luis Antonio de 01 November 2005 (has links)
Imazethapyr was recently approved for use in rice, but limited information is available regarding its efficacy, environmental fate or potential red rice resistance. Therefore, experiments were conducted to 1) determine the effect of flooding time, and stage of imazethapyr application in red rice control, 2) assess the acetolactate synthase resistance to imazethapyr on red rice ecotypes, 3) determine the relative photolysis of imazethapyr, and 4) determine the effect of soil and moisture on imazethapyr adsorption and availability. When imazethapyr was applied in sequential application of PRE followed by a POST application, to achieve >95% red rice control, flood needed to be established within 14 DAT when imazethapyr was applied EPOST, and 7 DAT when imazethapyr was applied LPOST. Delaying the flood up to 21 DAT reduced rice grain yield for both EPOST and LPOST application timings. Based on enzymatic activity, the mean I50 values were 1.5, 1.1, 1.5, 1.6, 20.8, and 590.6 mM of imazethapyr, respectively, for LA 5, MS 5, TX 4, ??Cypress??, ??CL-121??, and ??CL-161??. CL-161 was 32 times more resistant than CL-121, and at least 420 times more resistant than the average of the red rice ecotypes and ??Cypress??. Results from the ALS assay showed that red rice ecotypes and Cypress had high susceptibility to imazethapyr when compared with the tolerant CL-121 and the resistant CL-161. Measurable enzymatic tolerance to ALS-inhibiting herbicides has not yet developed in these red rice ecotypes. Imazethapyr quantum yield (fI ) was 0.023 ?? 0.002 while the hydroxyl radical rate constant ( I OH k?? ) was 2.8 ?? 0.44 x 1013 M-1 h-1. These results show that imazethapyr is susceptible to both direct and indirect photolysis. The results also show that imazethapyr photolysis in paddy water will be affected by turbidity due to its impact on the availability of sunlight to drive direct and indirect photolysis reactions. Imazethapyr was more available and more concentrated in sandy soil. With higher amounts of water in soil there was greater amount of imazethapyr in soil solution and a lower concentration of herbicide due to dilution. The double centrifuge method provided a better estimate of plant available herbicide.
10

Antioxidant properties of spaghetti and infant cereals and characterization of major phenolic compounds by LC/MS analysis

Hirawan, Rhanissa 08 April 2011 (has links)
The present study investigated the antioxidant properties of commercial regular- and whole- wheat spaghetti. The antioxidant properties comprise the total phenolic content, DPPH radical scavenging activity, oxygen radical absorbance capacity. The contents of ferulic acid, C-glycosyl flavones and SDG were measured by using LC/MS techniques. Whole wheat spaghetti showed significantly higher TPC and ORAC. The contents of ferulic acid, C-glycosyl flavones and SDG were significantly higher in whole wheat spaghetti. The TPC was found to decrease 48 – 78% after cooking. The results showed that consumption of whole grain is strongly recommended. The present study also compared the antioxidant properties of commercial infant cereals. Purple wheat and red rice were used in making home-made and lab-made infant cereals. Pigmented infant cereals showed higher TPC, total anthocyanin content (TAC) and ORAC then brown rice and commercial ones. Anthocyanins were found only in purple wheat while a C-glycosyl flavone was found at higher levels in purple wheat than in red rice samples. Home-made samples did not show significant differences in TPC, TAC and ORAC with lab-made ones; however, the contents of anthocyanins and C-glycosyl flavones were significantly different. Home-made purple wheat infant cereals showed higher cellular antioxidant activity (CAA) than lab-made purple wheat, red rice and commercial ones. Whole purple wheat holds potential to improve the antioxidant properties of infant cereals.

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