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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.
121

Synchrony between catalases and ascorbate peroxidases in cowpea leaves protection against the water and salt stress-induced oxidative damage / Sincronia entre catalases e peroxidases de ascorbato na proteÃÃo contra danos oxidativos em folhas de feijÃo Caupi expostas aos estresses hÃdrico e salino

JoÃo Paulo Matos Santos Lima 03 July 2007 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Water stress, induced by drought or salinity, is the major environmental restriction to plant survive and crop sustainability, specially in semi-arid areas, where they are often associated to high temperatures and high radiation rates. Part of the effects exerted by these abiotic stresses on plant metabolism is mediated by oxidative damage due to an increased production of active oxygen species (AOS). The present study aims to elucidate the interactions and the importance of the catalase (CAT) and ascorbate peroxidase (APX) enzymatic antioxidants systems in the protection of cowpea leaf tissues [Vigna unguiculata (L.) Walp.] against the oxidative damage induced by water deficit and salinity. The experimental approach adopted, involved 3 different experiments, using PEG-induced water stress or NaCl-induced salt stress, combined to the CAT inhibitor 3-Amino-1,2,4-trizole (3-AT) application. These experiments were conduced under two environmental conditions: in a growth chamber, under controlled conditions, and in a greenhouse, under the typical semiarid conditions of the Brazilian Northeast. PEG and NaCl treatments were applied to the nutritive solution for 72 h, while the 3-AT was daily sprayed in the shoot. The osmotic stress induced by PEG or NaCl caused acute declines in the transpiration rates, due to increase in stomatal resistance, as well as an intense growth reduction, in the plants cultivated in the greenhouse conditions. The osmotic stressed plants presented significant increases on lipid peroxidation and on the ascorbate content, in addition to a CAT activity reduction. The osmotic stress and 3-AT combination raised the APX activity levels that counteracted, at least in part, the CAT absence. The fall in the CAT activity was related to a strong mRNA expression restraint, followed by an up-regulation of the cytosolic APX mRNA. These results indicate the presence of a controlled synchrony between the expression and enzymatic activity of these antioxidant systems, in the regulation and detoxification of the AOS produced in plant cells, during environmental stresses situations. / O estresse hÃdrico induzido por seca ou salinidade à a principal restriÃÃo ambiental à sobrevivÃncia das plantas e sustentabilidade das culturas, principalmente nas regiÃes semiÃridas, onde estÃo frequentemente associados a altas temperaturas e taxas de luminosidade. Uma grande parte dos efeitos destes estresses ambientais no metabolismo das plantas à mediada por danos oxidativos devido ao aumento na produÃÃo de espÃcies ativas de oxigÃnio (AOS). O presente estudo se propÃs a estudar a interaÃÃo e a importÃncia dos sistemas antioxidantes enzimÃticos da catalase (CAT) e da peroxidase de ascorbato (APX) na proteÃÃo dos tecidos foliares de feijÃo caupi [Vigna unguiculata (L.) Walp.] contra os danos oxidativos induzidos por condiÃÃes de deficiÃncia hÃdrica e salinidade. Para isso, foi utilizada uma abordagem experimental envolvendo 3 experimentos, utilizando combinaÃÃes de estresse hÃdrico, induzido por polietilenoglicol (PEG), ou salino, induzido por NaCl, com a pulverizaÃÃo do inibidor de catalases 3-Amino-1,2,4-Triazol (3-AT). Estes experimentos foram, ainda, realizados em duas condiÃÃes ambientais: uma em cÃmara de crescimento sob condiÃÃes controladas e em casa de vegetaÃÃo, sob condiÃÃes tÃpicas do semi-Ãrido. O PEG e o NaCl foram aplicados na soluÃÃo nutritiva durante 72 h, e o 3-AT pulverizado diariamente na parte aÃrea. O estresse osmÃtico causado pela aplicaÃÃo de PEG ou de NaCl induziu uma forte reduÃÃo na transpiraÃÃo, associada a uma maior resistÃncia estomÃtica, e uma acentuada reduÃÃo no crescimento nas plantas submetidas as condiÃÃes de casa de vegetaÃÃo. Houve um considerÃvel aumento na peroxidaÃÃo de lipÃdeos e do conteÃdo do antioxidante ascorbato das plantas tratadas, bem como uma diminuiÃÃo da atividade de CAT. As plantas submetidas a uma combinaÃÃo de estresse osmÃtico e a aplicaÃÃo do 3-AT apresentaram um acentuado aumento da atividade da enzima APX, compensando, em parte a ausÃncia da atividade da enzima CAT. Esta diminuiÃÃo da atividade enzimÃtica de CAT foi acompanhada por uma forte repressÃo dos mRNAs para esta enzima, enquanto que houve uma induÃÃo dos mRNAs da APX citossÃlica. Estes resultados indicam que hà uma controlada sincronia entre a expressÃo e a atividade enzimÃtica destes dois sistemas, na regulaÃÃo e desintoxicaÃÃo das AOS produzidas na cÃlula vegetal, durante situaÃÃes de estresse ambiental.
122

Study of the membrane lipid metabolism and associated genes in Vigna unguiculata (L.) Walp under combined abiotic stress (drought/ozone) / Estudo do metabolismo de lipÃdios de membrana e da expressÃo dos genes relacionados em cultivares de Vigna unguiculata (L.) walp sob estresses abiÃticos combinados (seca/ozÃnio)

Deborah Moura RebouÃas 31 October 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Global climate changes are responsible for the increased frequency of episodes of drought and high concentrations of tropospheric ozone, which can occur simultaneously reducing plant growth, limiting agricultural production and affecting the food supply for an increasing world population. These environmental stresses can lead to the overproduction of reactive oxygen species, promoting oxidative stress and causing metabolic imbalance. Cell membranes are the primary targets of damage induced by stresses and the preservation of cell integrity through remodeling of membrane lipids is essential for plant survival under adverse conditions. The objective of this study was to investigate the effects of drought, ozone and the combined stresses in two cowpea cultivars with different degrees of drought tolerance: EPACE-1 (tolerant) and IT83-D (susceptible) through physiological responses and a study focused on the content and composition of membrane lipids, as well as on the expression of genes related to the biosynthesis and degradation of these lipids. Drought and ozone (120 ppb), isolated or in combination, were applied on three-week-old seedlings during two weeks. After 7 and 14 days of treatments, physiological parameters were determined. Lipids extracted from leaves were analyzed by gas chromatography/mass spectrometry. Transcript accumulation (VuMGD1, VuMGD2, VuDGD1, VuDGD2, VuCLS, VuFAD7, VuFAD8, VuPLD1 and VuPAT1) was detected in leaves by real time PCR. In both cultivars, drought inhibited the plant growth and photosynthesis through stomatal closure, which appeared to involve the gene expression of phospholipase D (VuPLD1). Ozone caused foliar injury and degradation of galactolipids, mainly in IT83-D. In this cultivar, the damage resulted in an increase in DGDG:MGDG ratio and in VuDGD2 expression. Furthermore, a partial decrease in the phospholipids content in response to ozone was associated with an increase in VuPLD1 expression, suggesting a replacement of phospholipids by DGDG. Differently, EPACE-1 cultivar in the presence of ozone, concomitantly with the degradation of galactolipids, showed an increase in storage lipids and DPG (cardiolipin) contents. The two stresses in combination led to results similar to those observed in response to the drought treatment alone, in both cultivars, which likely reflected the severe restriction of ozone uptake resulting from drought-induced stomatal closure. In conclusion, the present results highlight the prominent role of membrane lipids in the metabolic adjustments that occur for the plant tolerance to drought and ozone. / As mudanÃas climÃticas globais sÃo responsÃveis pelo aumento da frequÃncia de episÃdios de seca e de elevadas concentraÃÃes de ozÃnio troposfÃrico, que podem ocorrer simultaneamente, reduzindo o crescimento das plantas, limitando a produÃÃo agrÃcola e afetando o suprimento de alimentos para a crescente populaÃÃo mundial. Esses estresses ambientais podem levar à superproduÃÃo de espÃcies reativas de oxigÃnio, promovendo o estresse oxidativo e causando desequilÃbrio metabÃlico. As membranas celulares sÃo os primeiros alvos de danos induzidos por estresses e a preservaÃÃo da integridade celular atravÃs da remodelaÃÃo dos lipÃdios de membrana à essencial para a sobrevivÃncia da planta sob condiÃÃes adversas. O objetivo deste trabalho foi investigar os efeitos da seca, do ozÃnio e dos estresses combinados em dois cultivares de feijÃo-de-corda dotados de diferentes graus de tolerÃncia à seca: EPACE-1 (tolerante) e IT83-D (sensÃvel) atravÃs de respostas fisiolÃgicas e de um estudo focado no teor e na composiÃÃo de lipÃdios de membrana, assim como na expressÃo de genes relacionados à biossÃntese e à degradaÃÃo desses lipÃdios. A seca e o ozÃnio (120 ppb), isolados ou combinados, foram aplicados nas plantas apÃs trÃs semanas de germinaÃÃo, durante duas semanas. ApÃs 7 e 14 dias de tratamentos, parÃmetros fisiolÃgicos foram determinados. Os lipÃdios extraÃdos de folhas foram analisados por cromatografia gasosa/espectrometria de massa. O acÃmulo de transcritos (VuMGD1, VuMGD2, VuDGD1, VuDGD2, VuCLS, VuFAD7, VuFAD8, VuPLD1 e VuPAT1) foi detectado em folhas por PCR em tempo real. Em ambos os cultivares, a seca inibiu o crescimento e a fotossÃntese atravÃs do fechamento estomÃtico, o que pareceu envolver a expressÃo gÃnica da fosfolipase D (VuPLD1). O ozÃnio causou injÃria foliar e degradaÃÃo de galactolipÃdios, principalmente em IT83-D. Neste cultivar, os danos implicaram no aumento da relaÃÃo DGDG:MGDG e da expressÃo de VuDGD2. AlÃm disso, uma diminuiÃÃo parcial no teor de fosfolipÃdios em resposta ao ozÃnio foi associada ao aumento da expressÃo de VuPLD1, sugerindo-se uma substituiÃÃo de fosfolipÃdios por DGDG. Diferentemente, o cultivar EPACE-1 em presenÃa de ozÃnio, concomitantemente com a degradaÃÃo de galactolipÃdios, mostrou um aumento nos teores de lipÃdios de reserva e de DPG (cardiolipina). A combinaÃÃo dos estresses levou a resultados semelhantes aos encontrados com a seca aplicada isoladamente, em ambos os cultivares, o que provavelmente reflete a forte restriÃÃo da absorÃÃo de ozÃnio devido ao fechamento dos estÃmatos induzido pela seca. Em conclusÃo, os presentes resultados ressaltam o proeminente papel dos lipÃdios de membrana nos processos de ajustamento metabÃlico que ocorrem para regular a tolerÃncia das plantas à seca e ao ozÃnio.
123

Simbiose feij?o-caupi e riz?bio: diversidade de bact?rias associadas aos n?dulos / Symbiosis cowpea and rhizobia: bacteria diversity associated to root nodules

LEITE, Jakson 27 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-23T18:13:31Z No. of bitstreams: 1 2015 - Jakson Leite.pdf: 1055808 bytes, checksum: fa105f74410a81a1f30e45ae5e911c9d (MD5) / Made available in DSpace on 2017-08-23T18:13:31Z (GMT). No. of bitstreams: 1 2015 - Jakson Leite.pdf: 1055808 bytes, checksum: fa105f74410a81a1f30e45ae5e911c9d (MD5) Previous issue date: 2015-02-27 / CAPES / Cowpea [Vigna unguiculata (L.) Walp] is an important crop in northeastern Brazil with strategic advantages for production in semi-arid region, such its drought tolerance and good performance in low fertility soils. In addition, the nitrogen (N) fixed in symbiosis with rhizobia eliminates the demand for N fertilizers, with economic, social and environmental benefits. Little is known about the genetic diversity of bacteria associated to cowpea nodules in Brazilian semi-arid. The aim of the study was to characterize the bacterial diversity of Brazilian semi-arid soils associated with nodules of different cowpea cultivars by dependent and independent bacterial cultivation strategy. Initially a collection of 86 bacteria cowpea nodules isolated from semiarid soils was genetically characterized by partial 16S rRNA gene sequencing and symbiotic genes nifH and nodC. The sequences were compared with the NCBI database to identify isolates and phylogenetic relationships were built. In another study, we applied the independent cultivation method to evaluate bacterial communities associated with the nodules of two cowpea cultivars (BRS and BRS Acau? Pujante), in Ultisol with no history of cowpea cultivation. Nodules (N) were collected 35 days after germination, and soil samples (BS) from 0-20 cm deeper. DNA was extracted for analysis of bacterial communities with 454 pyrosequencing of the 16S ribosomal gene rRNA. The analysis of the diversity of the bacterial collection of the nodules 54 of the 86 isolates were Bradyrhizobium. Other (32) belong to Rhizobium (13) and Microvirga (1), Alfaproteobact?ria class; Burkholderia (8), and Ralstonia (1), Betaproteobacteria class; Acinetobacter (1), Cronobacter (3), Enterobacter (1), and Pantoea (1), Gamaproteobact?ria; and Leifsonia (3), phylum Actinobacteria. As Bradyrhizobium predominated, analyzes were performed with the almost full 16S rRNA, nifH and nodC and isolates were distributed in 5 lines: 16S rRNA type I (44 isolates), type II (6), Type III (1), Type IV ( 2) and type IV (1). Phylogenetic analysis of the 16S rRNA gene grouped the Type I strain in the large group Bradyrhizobium japonicum and close to the type strain of Bradyrhizobium yuanmingense. The analyses of the nifH and nodC gene separated the isolates in 5 symbiotic lines (I, II, III, IV and IV) and were congruent among them, which supports the theory of monophyletic in origin symbiotic gene Bradyhrizobium. The symbiotic lineages I and II are nearby and correspond to all isolates with 16S rRNA type I, being the dominant group associated with nodules. The partial 16S rRNA gene sequencing of bacterial communities showed high diversity in the three environments (BS, RS and N). The communities associated with the nodes were significantly different (p> 0.01) from the surrounding nodules (LS and RS). Phyla Actinobacteria, Bacteriodetes, Proteobacteria were plentiful for BS and RS. In nodes, the Proteobacteria and Bacteriodetes phyla predominated, Gammaproteobacteria being (58.8%) and Alphaproteobacteria (37.4%) in the phylum Proteobacteria and dominant Flavobacteriia (84.8%) and Sphingobacteriia (10.9%) in the phylum Bacteriodetes. For gender, Chryseobacterium, Entreobacter and Bradyrhizobium dominate in all nodes samples where Chryseobacterium prevailed in BRS Acau? and Enterobacter in BRS Pujante. / O feij?o-caupi [Vigna unguiculata (L.) Walp] ? uma das principais culturas no Nordeste do Brasil com vantagens estrat?gicas para produ??o no semi?rido, como toler?ncia a seca e bom desempenho em solos de baixa fertilidade. Al?m disso, fixa N em simbiose com riz?bios eliminando a demanda de fertilizantes nitrogenados, com benef?cios econ?micos, sociais e ambientais. Pouco se sabe sobre a diversidade gen?tica de bact?rias associadas aos n?dulos de feij?o-caupi no semi?rido. O objetivo do estudo foi caracterizar a diversidade de bact?rias de solos do semi?rido brasileiro associadas aos n?dulos de diferentes cultivares de feij?o-caupi com arbordagem que depende e independe de cultivo das bact?rias. Inicialmente uma cole??o de 86 bact?rias de n?dulos de feij?o-caupi isoladas de solos do semi?rido foi caracterizada geneticamente pelo sequenciamento parcial do gene 16S rRNA e dos genes simbi?ticos nifH e nodC. As sequ?ncias foram comparadas com as do banco de dados do NCBI para identificar os isolados e as rela??es filogen?ticas dos mesmos com as de esp?cies conhecidas. Em outro estudo, aplicou-se o m?todo independente de cultivo para avaliar comunidades de bact?rias associadas aos n?dulos de dois cultivares de feij?o-caupi (BRS Pujante e BRS Acau?), em Argissolo Amarelo sem hist?rico de uso com a lavoura. Os n?dulos (N) foram coletados 35 dias ap?s a germina??o e a amostragem do solo (BS) de 0-20 cm. O DNA das amostras foi extra?do para an?lises das comunidades bacterianas com 454 pirosequenciamento do gene ribossomal 16S rRNA. Na an?lise da diversidade da cole??o de n?dulos 54 dos 86 dos isolados foram de Bradyrhizobium. Os demais (32) pertencem aos g?neros Rhizobium (13) e Microvirga (1), classe Alfaproteobact?ria; Burkholderia (8) e Ralstonia (1), classe Betaproteobact?ria; Acinetobacter (1), Cronobacter (3), Enterobacter (1) e Pantoea (1), Gamaproteobact?ria; e Leifsonia (3), filo Actinobact?ria. Como Bradyrhizobium predominou, foram feitas an?lises com os genes 16S rRNA, nifH e nodC e os isolados distribu?ram-se em 5 linhagens: 16S rRNA tipo I (44 isolados), tipo II (6), tipo III (1), tipo IV (2) e tipo IV (1). A an?lise filogen?tica do gene 16S rRNA agrupou a linhagem tipo I no grande grupo Bradyrhizobium japonicum e pr?ximo da estirpe tipo de Bradyrhizobium yuanmingense. A an?lise dos genes nifH e nodC separou os isolados em 5 linhagens simbi?ticas (I, II, III, IV e IV) e as ?rvores foram congruentes, o que suporta a teoria da origem monofil?tica de genes simbi?ticos em Bradyhrizobium. As linhagens simbi?ticas I e II s?o pr?ximas e correspondem a todos os isolados com 16S rRNA tipo I, sendo o grupo dominante associado aos nodulos. O sequenciamento parcial do gene 16S rRNA das comunidades bacterianas mostrou alta diversidade nos tr?s ambientes (BS, RS e N). As comunidades associadas aos n?dulos foram significativamente diferentes (p> 0,01) das que cercam os n?dulos (LS e RS). Os filos Actinobacteria, Bacteriodetes, Proteobacteria foram abundantes para BS e RS. Em n?dulos, os filos Proteobacteria e Bacteriodetes predominaram, sendo Gammaproteobacteria (58,8%) e Alphaproteobacteria (37,4%) dominantes no filo Proteobacteria e Flavobacteriia (84,8%) e Sphingobacteriia (10,9%) no filo Bacteriodetes. Para g?nero, Chryseobacterium, Entreobacter e Bradyrhizobium dominam em todas as amostras de n?dulos, onde Chryseobacterium predominou em BRS Acau? e Enterobacter em BRS Pujante.
124

Nodula??o e desenvolvimento do feij?o-caupi em fun??o de diferentes doses de P, Co e Mo / Nodulation and development of cowpea bean under different dosages of P,Co and Mo

PAULO, Fernanda Santana de 27 February 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-10-04T17:35:36Z No. of bitstreams: 1 2013 - Fernanda Santana de Paulo.pdf: 1349643 bytes, checksum: 8da583439baf6dcac85c9ddb6af5ffbc (MD5) / Made available in DSpace on 2017-10-04T17:35:36Z (GMT). No. of bitstreams: 1 2013 - Fernanda Santana de Paulo.pdf: 1349643 bytes, checksum: 8da583439baf6dcac85c9ddb6af5ffbc (MD5) Previous issue date: 2013-02-27 / CAPES / Embrapa / The cowpea bean is a legume that has a wide economic potential, but it has not been explored efficiently. For this reason it has shown a yield potential far from the expectations of a so efficient legume in NBF as can be. The objective of this study is to obtain appropriate levels of P, Co, Mo nutrients. It is believed that these nutrients can optimize nodulation, nitrogen biological fixation and the growth of cowpea bean plants in representative soils from Cerrado, Mato Grosso. Based on the chemical analysis from the soil cited before, calculations for fertilization and liming were made. From the results obtained, were established doses for the elements of the present work (P, Co and Mo). The experiment was conducted in a greenhouse conditions and performed in a randomized block design. It was used a factorial arrangement 2 x 5 (2 soils; five doses of each element of the present study ? inoculated with 3262 strain) + 1 + 3 replicates. The additional treatment (+1) was included to evaluate crop performance when applied 50 Kg.ha-1 of nitrogen. The study was split in two trials. In the first trial, different dosages of phosphorous were tested: control (without Phosphorus application); low (44 mg.vase-1 of P), medium (88 mg.vase-1 of P), medium-low (130mg.vase-1 of P) and high (175 mg.vaso-1 of P). These tests were made to obtain a optimum dosage. In the second trial, cobalt and molybdenum nutrient was tested as the following levels respectively: 0, 2, 3, 4, 6 mg and 0, 8, 16, 32 and 64 mg. In the thirty-fifth day, the experiment developed in a greenhouse was collected. From the plants were evaluated height and plant diameter, nodulation (dry matter and number of nodules), shoot dry matter, root dry matter, chlorophyll content and N accumulation in shoot. The 88mg of P.vase-1 dosage that corresponds to 200 kg.ha-1 of P2O5 and the medium-high Cobalt and Molybdenum dosage that corresponds the application of 32g of Mo.ha-1 + 4g.ha-1 of Co provided higher nodulation in cowpea bean plants with consequent increase of biomass and nitrogen accumulation. The site where soil was collected had influence on the development and on the nodulation of the cowpea bean crop, when submitted to different dosages of P and Co+Mo. / O feij?o-caupi ? uma leguminosa de vasto potencial econ?mico, por?m n?o est? sendo explorado de maneira eficiente apresentando-se com potencial produtivo bem aqu?m das expectativas de uma leguminosa t?o eficiente em FBN. Sendo ent?o, o objetivo deste trabalho obter os n?veis adequados dos nutrientes P, Co e Mo que otimizem a nodula??o, a fixa??o biol?gica de nitrog?nio e o crescimento de plantas de feij?o-caupi em solos representativos do Cerrado do Mato Grosso. Com base na an?lise qu?mica do solo, foram realizados os c?lculos da necessidade de calagem e aduba??o e foram estabelecidas as doses dos elementos em estudo (P, Co e Mo). O experimento foi realizado em condi??es de casa de vegeta??o. O delineamento experimental foi em blocos ao acaso em esquema fatorial 2 x 5 (2 solos; 5 doses de cada elemento de estudo ? inoculadas com a estirpe 3262) +1 e 3 repeti??es. O tratamento adicional (+1) foi inclu?do para avaliar o desempenho da cultura na dose de N proporcional a 50 kg.ha-1. O trabalho foi dividido em dois ensaios, onde primeiro foram testadas dosagens diferenciadas de f?sforo que foram denominadas: controle, (sem aplica??o de F?sforo); baixa (44 mg.vaso-1 de P), m?dia (88 mg.vaso-1 de P), m?dia-alta (130 mg.vaso-1 de P), alta (175 mg.vaso-1 de P) para a obten??o de uma dosagem ?tima. Na segunda fase, foram testados os micronutrientes Co nas doses: 0, 2,3 ,4 ,6 mg e Mo nas doses: 0, 8, 16, 32 e 64 mg. Em casa de vegeta??o, aos 35 dias foi feita a coleta, as vari?veis avaliadas foram: altura e di?metro da planta, nodula??o (massa de n?dulos secos e n?mero de n?dulos), massa seca da parte a?rea, massa seca da raiz, teor de clorofila e ac?mulo de N na parte a?rea. A dose de 88 mg de P. vaso-1, que corresponde a 200 kg.ha-1de P2O5 e at? a dose m?dia-alta de cobalto e molibd?nio com correspondente a aplica??o de 32 g de Mo. ha-1 + 4 g ha-1de Co proporcionou maior nodula??o das plantas de feij?o-caupi com consequente aumento da biomassa do vegetal e ac?mulo de nitrog?nio. O local de coleta de solo influenciou no desenvolvimento e nodula??o da cultura do feij?o-caupi, quando submetida a diferentes doses de P e Co+Mo.
125

Water Supply in Tanzania and Performance of Local Plant Materials in Purification of Turbid Water

Marobhe, Nancy January 2008 (has links)
Water supply services in urban and rural areas of Tanzania were reviewed and specific studies were carried out on water supply and on purification of turbid water sources using locally available plant materials in rural villages of Singida Rural District. The review showed that large proportions of urban and rural populations in Tanzania face acute water supply problems mainly due to poor planning, implementation and management of water supply projects, including an inability to address social, technical, operation and maintenance and financial issues. Laboratory-scale experiments studied the effectiveness of crude seed extracts (CSEs) and purified proteins of Vigna unguiculata (VUP), Parkinsonia aculeata (PAP) and Voandzeia subterranea (VS) seeds, which are used traditionally for clarification of turbid water. The VUP and PAP were purified from CSEs using simple and straightforward two-step ion exchange chromatography. The coagulant proteins are thermoresistant and have a wide pH range for coagulation activity. Coagulation of turbid waters with CSEs, VUP and PAP produced low sludge volumes and removed turbidity along with other inorganic contaminants in line with Tanzania drinking water quality standards. The PAP also showed antimicrobial effect against river water bacteria. Citrus fruit juice (CF) enhanced the coagulation of turbid water by CSEs and inhibited bacterial growth, rendering it useful for disinfection of water prior to drinking in rural areas. It was concluded that natural coagulants should not be regarded as a panacea for rural water supply problems, but rather a tool in the development of sustainable water supply services in Tanzania. / QC 20100825
126

Anti-inflammatory Effect of Vigna Unguiculata Polyphenols in Raw 264.7 Macrophages

Siska, Karla P 08 October 2013 (has links)
This study investigated the association between flavonoid profiles of different cowpea (Vigna Unguiculata) varieties with anti-inflammatory properties as a possible benefit against inflammatory bowel disease. Cowpea, a drought tolerant annual herbaceous legume that originated in Africa, is known to possess high levels of polyphenolics, which have demonstrated anti-inflammatory, immunoregulatory and antioxidant properties. Black, red, white, brown and light brown cowpeas were investigated for phenolic content and composition using UV-Visible Spectroscopy and HPLC; antioxidant activation mechanism (AOX) by oxygen radical absorbance capacity (ORAC). Anti-inflammatory activity was measured via NF-κB activation in Raw 264.7 macrophages challenged with a lipo-polysaccharide. Phenols, tannins and AOX activity were generally similar within phenotypes; however among light brown varieties, 09FCV-CC-27M, had among the highest phenols, tannins and AOX, whereas IAR-48 had among the lowest. White cowpea (EARLY ACRE) variety showed the least amount of total phenol content (78.2 mg GAE/g) and condensed tannin content (4.1 mg CE/g); whereas the red varieties (IT82D-889, IT97K-1042-3) contained the highest amounts of tannins (242 and 132 mg CE/g), and phenols (431 and 454 mg GAE/g) respectively. Antioxidant activity correlated with phenol content data. Anthocyanins were only found in the black cowpea. The red varieties had the highest levels of flavonols, which were mostly quercetin derivatives; the white and light brown (IAR-48) varieties had quercetin-3-O-diglucoside as the dominantcompound. The light brown variety (09FCV-CC-27M) had the highest amount of flavan-3-ols while in the white variety no flavan-3-ols were detected. Unexpectedly, the cowpea extracts with lower phenolic and tannins content, the white and light brown (IAR-48) varieties, showed significant (p<0.05) anti-inflammatory properties in the LPS induced macrophages, inhibiting the activation of NF-κB at different concentrations (0.33, 1.67 and 3.33 μg extract/mL). Conversely, extracts with higher phenolic and tannin content did not induce anti-inflammatory response at similar concentrations, suggesting that tannins or other phenolics interfered with anti-inflammatory response at these concentrations. These results suggest that cowpea composition is an important determinant of anti-inflammatory response in inflammatory bowel disease.
127

Severidade de isolados de Macrophomina spp. de plantas daninhas a feijão-caupi / Severity of Macrophomina spp. from weed to cowpea

Silva Neto, Alfredo Nogueira da 12 July 2017 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-12-21T14:52:27Z No. of bitstreams: 1 AlfredoNSN_DISSERT.pdf: 517385 bytes, checksum: 2cd80874c311dec2c7e627a39c2b9f2e (MD5) / Rejected by Socorro Pontes (socorrop@ufersa.edu.br), reason: corrigir referencia on 2017-12-22T13:44:44Z (GMT) / Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-12-22T13:45:50Z No. of bitstreams: 1 AlfredoNSN_DISSERT.pdf: 517385 bytes, checksum: 2cd80874c311dec2c7e627a39c2b9f2e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-02-20T14:29:34Z (GMT) No. of bitstreams: 1 AlfredoNSN_DISSERT.pdf: 517385 bytes, checksum: 2cd80874c311dec2c7e627a39c2b9f2e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-02-20T14:32:10Z (GMT) No. of bitstreams: 1 AlfredoNSN_DISSERT.pdf: 517385 bytes, checksum: 2cd80874c311dec2c7e627a39c2b9f2e (MD5) / Made available in DSpace on 2018-02-20T14:32:17Z (GMT). No. of bitstreams: 1 AlfredoNSN_DISSERT.pdf: 517385 bytes, checksum: 2cd80874c311dec2c7e627a39c2b9f2e (MD5) Previous issue date: 2017-07-12 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The fungus Macrophomina phaseolina is a polyphagous phytopathogen, which attacks more than 600 species of plants, including weeds that can host it. Pega-pinto (Boerhavia diffusa L.) and bredo (Trianthema portulacastrum L.) are common weeds that occur in areas of feijão-caupi (Vigna unguiculata L.), in Rio Grande do Norte and Ceará. When infected by M. phaseolina, this culture causes gray stem rot, drastically reducing yield. Therefore, the present work aimed to verify the virulence of Macrophomina spp. obtained from pega-pinto and bredo. The experiments were conducted in Vegetation House of the Universidade Federal Rural do Semi-Árido (UFERSA), in Mossoró-RN. Two trials were carried out to evaluate the severity of 100 isolates of Macrophomina, not first to posteriori 50 isolates in the pega-pinto roots and, in the second, 50 isolates from roots of bredo. In both assays, a Macrophomina Feijão-caupi isolate was used. The experimental design was completely randomized, with five replicates. All 50 isolates of Macrophomina spp. caused gray stem rot symptoms in caupi and 64% these isolate showed a similar severity to the caupi isolate. In the bredo, 90% of the isolates caused the disease, however none of them presented severity equal to the caused by caupi isolates / O fungo Macrophomina phaseolina é um fitopatógeno polífago que ataca mais de 600 espécies de plantas, incluindo espécies daninhas que podem ser suas hospedeiras. Pega-pinto (Boerhavia difusa L.) e bredo (Trianthema portulacastrum L.) são espécies daninhas que ocorrem com frequência em áreas de produção do feijão-caupi (Vigna unguiculata L.), no Rio Grande do Norte e Ceará. Quando infectada por M. phaseolina, esta cultura causa a podridão cinzenta do caule, reduzindo drasticamente a produção. Sendo assim, o presente trabalho teve como objetivo verificar a severidade de isolados de Macrophomina spp. obtidos de pega-pinto e bredo. Os experimentos foram conduzidos em Casa de Vegetação da Universidade Federal Rural do Semi-Árido (UFERSA), no município de Mossoró-RN. Foram realizados dois ensaios para avaliar a severidade de 100 isolados de Macrophomina. No primeiro, foram avaliados 50 isolados provenientes das raízes de pega-pinto e, no segundo, 50 isolados oriundos de raízes de bredo. Em ambos os ensaios, utilizou-se um isolado de Macrophomina de feijão-caupi. O delineamento utilizado nos experimentos foi o inteiramente casualizado, com cinco repetições. Todos os 50 isolados de Macrophomina spp. oriundos de pega-pinto causaram sintomas de podridão cinzenta do caule nas plantas de feijão-caupi e 64% destes isolados apresentaram incidência igual ao isolado oriundo de caupi, entretanto apenas um isolado apresentou severidade igual ao isolado do caupi. Para o bredo, 90% dos isolados causaram a doença, porém, nenhum deles tendo apresentado severidade igual à ocasionada pelo isolado de feijão-caupi / 2017-12-19
128

Horticulture production in conditions of Sub-Sahara Africa

Milanda, Johannes January 2014 (has links)
This paper was written to provide the literature review on the topic of horticultural production in Namibia or in neighboring countries, with a focus on vegetable species. To suggest a prospective representative vegetable species from the study area, which could have production potential in the Czech Republic. Four chosen cultivars (Metro, Nakare, Bira and Shidimba) from the Cowpea (Vigna uinguiculata L Walp) species were experimentally tested in conditions of the Czech Republic. They were grown naturally extensively with no fertilizers, herbicides or pesticides used. They're morphological parameters were then recorded and laboratory analyzed using ANOVA and three valuables [flavonoids, total antioxidants capacity (TAC) and polyphenols] were determined using different methods with the spectrophotometry.
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Avaliação de um ciclo de rotação cultural milho e feijão-de-corda, utilizando-se água de baixa e de alta salinidade. / Evaluation of a cycle of the crop rotation of corn-and bean-string, using water of the low and high salinity.

Sousa, Geocleber Gomes de January 2008 (has links)
SOUSA, G. G. Avaliação de um ciclo de rotação cultural milho e feijão-de-corda, utilizando-se água de baixa e de alta salinidade. 2008. 92 f. Dissertação (Mestrado em Agronomia/Solos e Nutrição de Plantas) - Centro de Ciências Agrárias, Universidade Federal do Ceará, Fortaleza, 2008. / Submitted by Francisco Lacerda (lacerda@ufc.br) on 2014-09-02T21:22:55Z No. of bitstreams: 1 2008_dis_ggsousa.pdf: 1395455 bytes, checksum: 5a27d3e7fd45c48510f1bbd48c2dbd9e (MD5) / Approved for entry into archive by José Jairo Viana de Sousa(jairo@ufc.br) on 2014-09-03T18:20:53Z (GMT) No. of bitstreams: 1 2008_dis_ggsousa.pdf: 1395455 bytes, checksum: 5a27d3e7fd45c48510f1bbd48c2dbd9e (MD5) / Made available in DSpace on 2014-09-03T18:20:53Z (GMT). No. of bitstreams: 1 2008_dis_ggsousa.pdf: 1395455 bytes, checksum: 5a27d3e7fd45c48510f1bbd48c2dbd9e (MD5) Previous issue date: 2008 / Aiming to assess the effects of salinity in the chemical characteristics of the soil, growth, partition of dry matter and productivity, and the effects of soil salinity on the levels mineral elements contend and the total extracted Na, macronutrients (Ca, K, Mg, P) and micronutrients (Cl, Fe, Cu, Zn and Mn), according to the salinity of the water irrigation, an experiment was carried out in the field according with randomized block design, with four treatments (T1, T2, T3 and T4) and five repetitions. In the cropping rotation was planted the maize in the spacing between lines of 0.8 m and 0.2 m between plants irrigated with water from high salinity and cowpea in the spacing between lines of 0.8 m and 0.3 m between plants irrigated with water with low salinity. The treatments used in the dry season maize crop in were: T1 (plants irrigated with water with low salinity), T2 (saline water with ECw of 2.2 dS m-1); T3 (saline water with ECw of 3.6 dS m-1); T3 (saline water with ECw ds of 3.6 m-1) and T4 (saline water with ECw of 5.0 dS m-1). For cropping of cowpea in the rainy season the plots were demarcated. During the rotation croppoing were assessed the following characteristics: chemical characteristics of soil, vegetation growth, partition of dry and productivity. They were also evaluated the levels of elements and minerals extracted from the total nutrients in the corn crop at 90 days after sowing. The application of saline waters caused increased salinity and sodicity soil during the dry period, and rainfall in the rainy season have been effective in washing the excess salts in the soil profile,increasing salinity of irrigation water above 2,2 dS m-1 reduced the vegetative growth, productivity and rate of harvest of maize, the accumulation of salts in the soil for the cultivation of maize in the dry season did not affect the productivity of cowpea, which was due to the high volume of rain that occurred just before and after the cultivation, this excess of rain, however, caused an no normal growth of cowpea with predominance vegetative of shares to the detriment of the production of grains. The levels of mineral elements varied in the maize crop to 90 days after the planting, being affected by salinity of irrigation water, as the higher the level of salinity irrigation water to 90 days after sowing as lower the levels of potassium in the leaves, magnesium and phosphorus in grains, and the plants of maize under low salinity irrigation water, extract nurtrient in the following order: K> Mg> Cl> Ca> P> Na> Fe> Zn> Mn> Cu however under salinity estress the maize crop extract the minerals to higher salinity level in the following order: K> Cl> Ca> Na> P> Mg> Mn> Zn> Cu and the salt decreases the extraction total the following minerals: K, Ca, Mg e P. The salinity has the following distribution of mineral elements: Na and K remained in the vegetative parts, Ca, Mg and P was exported in larger proportions to the reproductive organs, Cl, Mn and Cu were mainly in the vegetative parts, Fe and Zn was exported in larger proportions by grain. / O presente trabalho teve por objetivos avaliar os efeitos da água de baixa salinidade (0,8 dS m-1) e de alta salinidade (2,2; 3,6 e 5,0 dS -1) nos atributos químicos do solo, no desenvolvimento de plantas de milho (Zea mays l.) e feijão-de-corda (Vigna unguiculata L. (Walp), nos teores de elementos minerais e nos totais extraídos de Na, de macronutrientes (Ca, K, Mg, P,) e de micronutrientes (Cl, Fe, Cu, Zn e Mn), cultivadas em um ciclo de rotação cultural milho e feijão-de-corda. O experimento foi conduzido no campo em um Argissolo Vermelho Amarelo Eut´rofico (Santos et al., 2006) obedecendo a um delineamento em blocos ao acaso, com quatro tratamentos (T1, T2, T3 e T4) e cinco repetições. Na rotação cultural o milho foi plantado no espaçamento de 0,8 m entre linhas e 0,2 m. na estação seca (Set a Dez/2007) irrigados com água de alta salinidade. Os tratamentos aplicados no cultivo do milho foram os seguinetes: T1 (água de baixa salinidade com condutividade elétrica de 0,8 dS m-1); T2 (condutividade elétrica de 2,2 dS m-1); T3 (condutividade elétrica de 3,6 dS m-1) e T4 (condutividade elétrica de 5,0 dS m-1). Os tratamentos (T2, T3 e T4) representam as águas de alta salinidade. Na estação chuvosa (Jan a Abr/2008) sucedendo o milho, cultivou-se o feijão-de-corda. Nesse cultivo utilizou-se apenas irrigações suplementares com água de baixa salinidade (0,8 dS m-1). O delineamento estatístico aplicado na rotação cultural foi o de blocos ao acaso, com cinco repetições, totalizando 20 unidades experimentais. Cada parcela com 3 m de comprimento e 5 linhas de plantio, sendo utilizado milho na estação seca e feijão-de-corda na estação chuvosa. Durante a rotação cultural foram avaliadas as seguintes características: atributos químicos do solo, crescimento vegetativo, partição de matéria seca e produtividade. Na cultura do milho foram também avaliadas os teores dos elementos minerais e os totais extraídos de Na, Ca, K, Mg, P, Cl, fe, Cu, Zn e Mn em função da salinidade da água de irrigação. A irrigação com águas salinas aumentou a salinidade e a sodicidade do solo durante o período da estiagem, e as precipitações no período chuvoso foram eficientes para a lavagem do excesso de sais do perfil do solo, enquanto a salinidade da água de irrigação acima 2,2 dS m-1 inibiu o crescimento vegetativo e a capacidade produtividade do milho, já o acúmulo de sais no solo durante o cultivo do milho na estação seca não afetou a produtividade do feijão-de-corda e a um a predominância do crescimento vegetativo do feijão-de-corda em detrimento da produção de grãos ocorreu pelo excesso de chuvas. Aos 90 dias após a semeadura os teores de elementos minerais foram afetados pela salinidade da água de irrigação, o aumento da salinidade da água de irrigação, aos 90 dias após a semeadura inibiu a absorção de potássio nas folhas, de magnésio e fósforo nos grãos, a extração dos nutrientes e sódio pelas plantas irrigadas com água de baixa salinidade obedeceu à ordem: K > Mg > Cl > Ca > P > Na > Fe > Zn > Mn > Cu, e com águas salinas: K > Cl > Ca > Na > P > Mg > Fe > Mn > Zn > Cu e a salinidade provocou redução da extração dos elementos minerais: K, Ca, Mg e P. O estresse salino proporcionou a seguinte distribuição de elementos minerais: Na e K permaneceram nas partes vegetativas, Ca, Mg e P foram exportados em maiores proporções para os órgãos reprodutivos, Cl, Mn e Cu permaneceram preferencialmente nas partes vegetativas, Fe e Zn foram exportados em maiores proporções pelos grãos.
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Resistência do feijão-caupi a Colletotrichum truncatum / Resistance of cowpea to Colletotrichum truncatum

Belmino, Claudia Sponholz 12 July 2004 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-04-27T18:15:46Z No. of bitstreams: 1 texto completo.pdf: 237390 bytes, checksum: 76cf331b0ce8463a4d0ef25be2192638 (MD5) / Made available in DSpace on 2017-04-27T18:15:46Z (GMT). No. of bitstreams: 1 texto completo.pdf: 237390 bytes, checksum: 76cf331b0ce8463a4d0ef25be2192638 (MD5) Previous issue date: 2004-07-12 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os objetivos Colletotrichum deste truncatum de trabalho plantas foram: de i) obter isolados de feijão-caupi e testar sua patogenicidade; ii) estudar a relação entre a concentração de inóculo, o tempo de molhamento foliar e a idade das plantas de feijão-caupi no desenvolvimento da mancha-café causada por C. truncatum; iii) identificar genótipos de feijão-caupi com resistência à mancha-café; iv) quantificar os componentes epidemiológicos da resistência do feijão-caupi à mancha-café. Foram obtidos isolados de C. truncatum de diferentes regiões produtoras de feijão-caupi. O isolado BGR, obtido de Baixa Grande do Ribeiro-PI foi selecionado para os ensaios de resistência por ser o que esporulou abundantemente em meio de cultura BDA. Os isolados de C. truncatum obtidos de feijão-caupi e de soja foram igualmente patogênicos a ambas as culturas. A concentração do inóculo de 10 6 conídios/mL, incubação das plantas, após a inoculação, sob período de molhamento foliar de 48 horas e inoculação das plantas com três semanas de idade, foram as condições ideais para o desenvolvimento da doença. No ensaio de campo em José de Freitas-PI destacaram-se três genótipos classificados como imunes (AR-87- 435, IT89KD-260 e Sanzi-Sambili) e cinco altamente resistentes (TE97-309G-2, MNC99-548F-1, MNC99-542F-7, MNC99-537F-14 e MNC99-537F- 1). No campo em Teresina-PI, nenhum genótipo foi imune e quatro foram altamente resistentes (AR-87-435, IT91K-118-2, IT93K-452-1 e MNC99- 537F-14). Em casa de vegetação detectaram-se 18 genótipos imunes e 29 altamente resistentes. Não houve correlação entre a severidade da mancha- café e a produção de grãos. Vários genótipos foram considerados resistentes e podem ser utilizados como fontes de resistência à mancha-café nos programas de melhoramento de feijão-caupi. Analisando-se o comportamento de cada genótipo, nas diferentes condições testadas, destacaram-se: MNC99-537F-14, Sanzi-Sanbili, MNC99-548F-1, MNC99- 541F-18, TE97-309G-9, BR14-Mulato, Urubuquara-113, TE97-309G-10, TE97309G-13, MNC99-508G-2, MNC99-518G-1, MNC99541F-21, Vita-3, TE97-321G-3, MNC 99-537F-9, IT81D-1228-14, TE97-411-1F-9, TE97-411- 1F-16, MNC99-537F-7, MNC99-552F-1, IT98K-1101-5, MNC99-537F-4, MNC99-541F-6, IT93K-452-1, IT91K-118-2 e AR-87-435. A severidade da doença foi o componente epidemiológico que melhor discriminou os genótipos de feijão-caupi quanto às reações de resistência a C. truncatum, os demais componentes usados não foram eficientes. A resistência do cultivar BR14-Mulato (testemunha resistente) caracterizou-se por um maior período latente (PL), reduzido número de lesões com acérvulos (NLA) e grau de severidade e menor valor de área abaixo da curva de progresso da doença (AACPD). O cultivar BR3-Tracuateua (testemunha suscetível) apresentou menor período de incubação (PI) e PL, maior AACPD e grau de severidade. / The objectives of this work were: i) to obtain isolates of Colletotrichum truncatum from cowpea plants and to test their pathogenicity ii) to study the relationship among the inoculum concentration, the dew period and the cowpea plants' age for disease development; iii) to identify cowpea genotypes resistant to C. truncatum; iv) to quantify the epidemic components of the cowpea resistance to C. truncatum. Colletotrichum truncatum from different cowpea production areas were isolated. The BGR isolated, obtained from Baixa Grande do Ribeiro-PI, was selected to be studied due to its better sporulation in BDA culture medium. The C. truncatum isolates from cowpea and soybean were equally pathogenic to both crops. Three weeks of age, 10 6 conidium/mL and 48 hours of dew were the ideal conditions of dew period, conidial concentration and cowpea plants' age for disease development. In a cultivated cowpea field, in José de Freitas- PI, three immune (AR-87-435, IT89KD-260 and Sanzi-Sambili) and five highly resistant (TE97-309G-2, MNC99-548F-1, MNC99-542F-7, MNC99- 537F-14 and MNC99-537F-1) genotypes stood out. In the Teresina-PI field, four genotypes were highly resistant (AR-87-435, IT91K-118-2, IT93K-452-1 and MNC99-537F-14). Under greenhouse conditions 18 immune and 29 highly resistant genotypes were observed. No correlation was found among the disease severity and grain production. Several genotypes by being considered resistant can be used as resistance sources to C. truncatum in the cowpea improvement programs. For most of the environments and evaluated traits the genotypes MNC99-537F-14, Sanzi-Sanbili, MNC99- 548F-1, MNC99-541F-18, TE97-309G-9, BR14-Mulato, Urubuquara-113, TE97-309G-10, TE97309G-13, MNC99-508G-2, MNC99-518G-1, MNC99541F-21, Vita-3, TE97-321G-3, MNC 99-537F-9, IT81D-1228-14, TE97-411-1F-9, TE97-411-1F-16, MNC99-537F-7, MNC99-552F-1, IT98K- 1101-5, MNC99-537F-4, MNC99-541F-6, IT93K-452-1, IT91K-118-2 and AR- 87-435 stood out. The disease severity was an efficient epidemic component to discriminate the resistance reaction of cowpea genotypes to C. truncatum but others used components had low efficiency. The BR14-Mulato genotype resistance was characterized by a higher latent period (LP), reduced number of lesions with acervulus (NLA), severity and area below the disease progress curve (ABDPC). The susceptible BR3-Tracuateua genotype showed lower incubation period and lower LP, higher ABDPC and severity degree. / Tese importada do Alexandria

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