Orientador: André Rodrigues dos Reis / Resumo: O selênio (Se) é um nutriente para humanos e animais e um elemento benéfico para as plantas, sua baixa concentração nos solos do Brasil pode gerar deficiência nos animais e humanos. O fitato é a principal forma de reserva de fósforo (P) encontrado nas sementes de plantas, sendo considerado um “anti-nutriente” por formar complexos não digeríveis com nutrientes como Fe, Ca e Zn. Desta forma, existe a necessidade de se buscar alternativas para aumentar os teores de Se e reduzir o teor de fitato nas partes comestíveis de cultivares modernos. O objetivo do trabalho foi avaliar doses e fonte ótimas de Se a serem aplicadas em condições brasileiras, bem como a influência do Se na produção e qualidade nutricional em 29 genótipos de feijão-caupi. Para isso, foram desenvolvidos dois experimentos a seguir: Experimento 1: Foi avaliada a eficiência da biofortificação agronômica utilizando 2 fontes de Se (selenato e selenito) e 7 doses de Se (0; 2,5; 5,0; 10,0; 20,0; 40,0 e 60 g ha-1) aplicados via solo, foi realizada analise de fitatos nos grãos. Experimento 2: Foi realizado um experimento para caracterizar a absorção e acúmulo de Se, teor de fitatos, açucares, proteínas de reversa e amino ácidos nos grãos de diferentes genótipos de feijão-caupi, nesse experimento, 29 genótipos foram avaliados na presença e ausência de Se (0 e 25 kg ha-1), cultivados até o final do ciclo para a obtenção dos grãos. No experimento 1, observou-se que a aplicação de selenato proporciona maiores concentrações d... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

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.

Thesis (M.Sc. (Agronomy )) --University of Limpopo, 2007 / Intercropping is the growing of two or more crops simultaneously on the same field, and it is a common traditional practice among resource-poor farmers throughout the Limpopo Province of South Africa. Field studies were conducted at two locations in the province namely, the University of Limpopo experimental farm at Syferkuil, and a farmer’s field at Dalmada during the 2002/2003 growing season, to determine patterns of nodulation in cowpea and lablab varieties under sole culture and in an intercropping system with maize, variety SNK2147 and also to assess biomass accumulation and grain yielding abilities of the component crops in the system. The experiments were established as a randomized complete block design with three replications at each location. Treatments examined were sole maize, two cowpea cultivars: Bechuana white and Glenda; two lablab cultivars, Rongai and Common. The legumes were intercropped alternately within 90 cm inter-row spacing of maize, thus creating a distance of 45 cm between the maize and the legume rows. Cropping system had no effect on cowpea grain yield at Syferkuil, but at Dalmada cowpea yield was reduced. Maize grain yield was significantly affected by the cropping system at both Syferkuil and Dalmada. At both locations, the yields of all the intercropped maize were lower than those of the sole crop maize. The dry matter production of different cropping systems was generally similar during the different sampling dates. / the National Research Foundation,and the Gauteng Department of Agriculture Conservation and Environment

Phytophthora vignae, causal agent of stem and root rot of cowpea (Vigna unguiculata), was reported for the first time in Sri Lanka. The pathogen was found in cowpea field soils from 3 of 5 geographic regions sampled. Only one site however, had plants exhibiting disease symptoms. Of the eight cowpea varieties grown in Sri Lanka, four were shown to be relatively resistant; all other legumes inoculated were completely resistant. Two morphologic and physiologic races of P. vignae were identified among the 24 isolates recovered, based on differential pathogenicity on cowpea varieties. Bacteria isolated from field soils, and other known bacterial biocontrol agents, inhibited P. vignae in culture, but only three Sri Lankan isolates considerably suppressed the disease in greenhouse tests. Volatile substances produced by most bacteria inhibited mycelial growth and sporangial production by P. vignae. The increased pH of the exposed medium suggested the involvement of ammonia. Volatile inhibitors were produced by these bacteria in soil, but only with added substrate; Strain DF-3101 also reduced oospore germination in soil. Cowpea plants inoculated with the VA mycorrhizal (VAM) fungus Glomus intraradices in P. vignae-infested soil were larger than non-mycorrhizal plants, but only at low levels of the pathogen. VAM colonization was reduced at high levels of the pathogen, and root infection by the pathogen was reduced by VAM. The fungicides metalaxyl, fosetyl-Al, Banrot, and Manzate-200DF reduced in vitro mycelial growth, but at different concentrations. Sporangia formation and germination, and oogonia formation by P. vignae, was reduced significantly by metalaxyl and fosetyl-Al. In greenhouse tests, metalaxyl, even at low concentrations, reduced disease; Fosetyl-Al was effective at high concentrations; Manzate-200DF was effective as a soil drench but not as a foliar spray; Banrot effectively reduced disease at 50 mg a.i./L. Exposure of a bacterial biocontrol agent to these fungicides in vitro did not affect its capacity to subsequently produce volatile inhibitors, but exposure to 10 ug/ml of metalaxyl and 50 ug/ml of Manzate-200DF reduced its capacity to subsequently inhibit mycelial growth of P. vignae. / Graduation date: 1991

Cowpea (Vigna ungiculata L. Walp) is a major food and fodder legume in poor countries, particularly Sub-Saharan Africa countries. It is generally produced in sandy, acid soils, deficient in phosphorus (P) which severely limits its production. Because processed phosphate fertilizers are expensive and poorly available to farmers, rock phosphate is viewed as a cheap alternative phosphate source. The present study evaluated 696 U.S Core Collection and IITA cowpea accessions for adaptation to low soil P environments and for response to rock phosphate application. Subsequently, organic acid exudation by selected cowpea genotypes as a mechanism for P acquisition from Fe-oxide and Ca bound P was investigated. A low P soil from Nacogdoches pine forest was used to grow plants. There were two P treatments: 0 and 300 mg P/kg of soil as Tahoua (Niger) rock phosphate. At harvest, plant height, shoot and root dry weights were determined and total biomass and shoot-to-root ratios were computed. Shoot P contents of 100 selected accessions were measured. Sixteen accessions reflecting the wide array of responses observed were selected for the organic acid study. Plants were grown in a growth chamber hydroponically with no P and +P nutrient solutions for 3 weeks. Organic acids were collected in a CaCl2-KCl solution. The nature and quantity of the collected organic acids was determined. Cowpea accessions were significantly different in their ability to adapt to Pdeficiency stress and to acquire P from rock phosphate. The parameters most effective in separating the accessions were shoot mass and total biomass. This data will be potentially useful in the selection of cowpea germplasm for (1) adaptation to West African soils of low P fertility, and (2) ability to utilize P from poorly soluble rock phosphate. The predominant organic acid exuded by cowpea roots was a tricarboxylic acid not yet identified. There was surprisingly more exudation of this acid under +P than under –P conditions. Exudation was more highly correlated to roots than to shoots.

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.

Overall soil productivity is declining in the U.S. due to loss of soil organic matter (SOM). Decreased SOM lowers soil water storage, reduces water infiltration, slows aggregate formation, and depletes soil of nutrients. In many systems, crop nutrients are replaced by expensive synthetic fertilizers that can lead to environmental concerns. This practice is not economically or environmentally sustainable in the long term. To secure future soil use and crop production, sustainable management practices are needed to prevent further SOM depletion. Incorporating legumes into cropping systems is one alternative that can bolster soil organic C (SOC) (key indicator of SOM) and reduce N fertilizer applications through symbiotic legume N fixation. Three studies were conducted over multiple years at the Texas A&M AgriLife Research and Extension Center near Overton, TX. Annual cool- and warm-season legumes were evaluated as potential green manure crops and intercrops under grain sorghum [Sorghum bicolor (L.) Moench], high-biomass sorghum [Sorghum bicolor (L.) Moench], and annual forage cropping systems. These studies quantified legume soil moisture usage and C and N contributions to the soil and subsequent crop yields in East Texas. Primary project objectives were to maintain or maximize primary crop yields at reduced N fertilizer rates and to build SOC through the integration of legume green manures and intercrops. Green manuring cool-season legumes showed the most beneficial effect on SOC, soil total N, and crop yields; however, significant increases in yield were only detected after three years in rotation. Intercropping Iron-and-Clay cowpea (Vigna unguiculata L. [Walp]) decreased yield of both high-biomass sorghum and grain sorghum due to competitive vegetative growth. Iron-and-Clay did however improve biomass yields of high-biomass sorghum in two subsequent years when implemented as a green manure. Despite large N yields as high as 310 kg ha-1, impacts of legumes on annual forage crops was limited. Poor response was likely a result of previous field history in which a permanent warm-season grass pasture was cultivated for site preparation and mineralized SOC released substantial amounts of available N. Under low soil N conditions, legume green manures produce enough N to likely reduce N fertilizer requirements cost-effectively for subsequent crops in East Texas.

No description available.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 5 uppsatser.

Made available in DSpace on 2014-06-11T19:28:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-29Bitstream added on 2014-06-13T19:16:43Z : No. of bitstreams: 1 cruz_pl_me_botfca.pdf: 370611 bytes, checksum: c967531537c8ec8ab5ddf5f8592a5a08 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O feijão-caupi (Vigna unguiculata L. Walp.) apresenta grande importância econômica e social nas regiões Norte e Nordeste do Brasil e tem conquistado mercado na região Centro-Oeste. Dentre as pragas dessa cultura, destaca-se a mosca-branca Bemisia tabaci (Gennadius 1889) biótipo B (Hemiptera: Aleyrodidae), com grande importância econômica. O inseto causa danos diretos, através da sucção de seiva, e indiretos, devido à transmissão de vírus. Diante da importância desse inseto como praga na cultura do feijão-caupi e da necessidade de se estabelecer métodos alternativos de controle em relação ao método químico convencional, a presente pesquisa teve como objetivo avaliar o comportamento de genótipos de feijão-caupi frente ao ataque de B. tabaci biótipo B, visando identificar possíveis tipos de resistência. Inicialmente, foram realizados testes preliminares com 51 genótipos, divididos aleatoriamente em dois grupos, avaliando-se a atratividade e a preferência para oviposição com chance de escolha. Dentre estes, foram selecionados TE93-244-23 F-1, Patativa, BRS- Marataoã, MNC99-541-F-21, TE 94-309-G-9, TVU-36, BR 17 - Gurguéia, TE97-304-G-4, BRS – Urubuquara e BRS – Rouxinol (promissores quanto à resistência), Pingo-de-ouro-1-1, TVU-1593 e IT81 D-1045 Enramador (suscetíveis), além do genótipo Canapu (testemunha), para as etapas subsequentes. Com esses 14 genótipos selecionados foram realizados ensaios de atratividade, preferência para oviposição e preferência para alimentação e/ou antibiose com B. tabaci biótipo B. Na primeira etapa, em casa de vegetação, verificou-se que para o Grupo 1, os genótipos TE93-244-23 F-1, Epace 10, MNC99-541-F-21, MNC04-786-B87-2, BRS – Marataoã, Patativa, TE94 309 G-9, IT86 D-716-1 e Corujinha foram menos atrativos aos adultos... / Cowpea (Vigna unguiculata L. Walp.) has social and economic importance to several regions in Brazil, including North, Northeast and the Midwest. The silverleaf whitefly Bemisia tabaci (Gennadius 1889) biotype B (Hemiptera: Aleyrodidae) has caused considerable damage and yield loss to the cowpea crops. Damage caused by this insect is related to its feeding and also through the virus transmission. Due the importance of this insect pest to cowpea cultivation and the need to establish alternative control methods compared to conventional chemical method, the present study evaluated the performance of cowpea genotypes against B. tabaci biotype B, in order to identify possible types of resistance. Initially, preliminary free choice tests were conducted with 51 genotypes, evaluating attractiveness and oviposition preference. In the second phase, it was selected TE93-244-23 F-1, Patativa, BRS-Marataoã, MNC99-541 F-21, TE94-309 G-9, TVU-36, BR17 - Gurguéia, TE97-304-G-4, BRS – Urubuquara and BRS – Rouxinol (promising as resistance); Pingo-de-ouro-1-1, TVU- 1593 and IT81 D-1045 Enramador (susceptible), as well Canapu genotypes (control), for subsequent steps. With 14 selected genotypes tests for attractiveness, oviposition preference and antibiosis and/or feeding preference to B. tabaci biotype B were performed. In greenhouse (Group 1), the genotypes TE93-244-23 F-1, Epace 10, MNC99-541-F-21, MNC04-786-B87-2, BRS – Marataoã, Patativa, TE94-309 G-9, IT86 D-716-1 and Corujinha were less attractive to adults of B. tabaci biotype B; TE93-244-23 F-1, Patativa, BRS - Marataoã, MNC99-541 F-21 and TE94-309 G-9 expressed oviposition non-preference. IntoGroup 2, the genotypes BRS - Urubuquara, TVU-36, TE97-304 G-4, BRS-Potengi, IT82 D-889, BR 17 – Gurguéia and BRS – Rouxinol were... (Complete abstract click electronic access below)