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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.
161

Efeitos de estirpes de Rizóbio em cultivares de Caupi do agreste Paraibano

de Lucena Vieira, Carolina January 2007 (has links)
Made available in DSpace on 2014-06-12T23:17:08Z (GMT). No. of bitstreams: 2 arquivo9128_1.pdf: 550202 bytes, checksum: 28c3246e376fb56bce5fc9929ae0d424 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / A resposta de cultivares locais de caupi à inoculação com estirpes de rizóbios recomendadas pelas instituições de pesquisa e extensão, ainda não está bem estabelecida. Quatro estirpes rizobianas (BR2001, BR3267, EI6 e NFB700) foram avaliadas em seis cultivares (Sedinha, Corujinha, Canapu, Sempre verde, Azul e IPA-206) tradicionalmente plantadas no Agreste Paraibano. Num experimento conduzido em casa de vegetação foram usados vasos de Leonard, com substrato estéril e as plantas, colhidas 40 dias após germinação. BR 3267 e BR 2001 foram as estirpes mais efetivas com todas as variedades, resultando em nodulação, teores e conteúdos de N maiores que os obtidos com EI 6 e NFB 700. Entretanto, quanto à biomassa das plantas, só BR 2001 diferiu significativamente das duas últimas estirpes. NFB 700 e EI 6 apresentaram efeitos positivos apenas com Sedinha e em relação a duas variáveis: número de nódulos e biomassa de parte aérea. IPA-206 não nodulou com EI 6 e mostrou os mais baixos valores de biomassa, teores e conteúdos de N. Em geral, Sempre Verde e Sedinha foram as variedades com os melhores resultados, destacando-se Sempre Verde com boas respostas a inoculação com todas as estirpes
162

Antimicrobial activity and fumonisins associated with cowpea (Vigna unguiculata)

Kritzinger, Quenton 22 February 2006 (has links)
A survey involving 71 farmers from rural communities in Mpumalanga, South Africa was conducted to gather information regarding the importance and utilisation of cowpea. Cowpea was rated third most important in contributing to household security, preceded by maize and vegetable production. Cowpea was mainly produced for own consumption, as a source of income and as fodder for livestock to a lesser extent. The crop was used by 8.5% of the farmers for medicinal purposes. Results indicated that 20% of the farmers encountered problems with mouldiness during storage, with insect infestation to a lesser degree. Cowpea seed samples from South Africa and Benin, West Africa were analysed for seed mycoflora and various fungal genera, particularly Aspergillus, Phoma and Lasiodiplodia were recorded. The results indicated an array of Fusarium spp. including F. equiseti, F. chlamydosporum, F. graminearum, F. proliferatum, F. sambucinum, F. scirpi, F. semitectum and F. subglutinans. The seed samples and the F. proliferatum isolates, cultured on maize patty media, were analysed for fumonisin production. Samples were extracted with methanol/water (70:30) and cleaned-up on strong anion exchange solid phase extraction cartridges. High-performance liquid chromatography with pre-column derivatisation using o-phthaldialdehyde was used for the detection and quantification of FB1, FB2 and FB3. The cowpea cultivars from South Africa had levels of FB1 ranging between 0.12 – 0.61 µg/g. All the F. proliferatum isolates produced FB1, FB2 and FB3 with total fumonisin concentration levels between 0.80 - 25.30 µg/g. The highest level of FB1 detected was 16.86 µg/g. Surface-disinfected seeds were imbibed in sterile distilled water amended with FB1 to yield final concentrations of 10, 25, 50 and 100 ppm. Percentage germination was determined in paper towels according to the International Seed Testing Association (ISTA) rules. Root and shoot length was measured after 9 days. All the toxin concentrations significantly decreased seed germination whilst root and shoot elongation was inhibited by the 50 and 100 ppm concentrations. Embryonic seed tissue treated with FB1 indicated compaction of the protoplasm and separation of the plasma membrane from the cell wall. Lipid bodies accumulated and seemed to line the cell wall. Acetone and ethanol extracts of the leaves of two cowpea cultivars exhibited significant inhibition of the growth of fungal plant pathogens at 5.0 mg/ml, with the exception of Fusarium equiseti. The growth of some fungi, in particular Alternaria alternate, was also reduced by lower concentrations of certain extracts. Acetone extracts of the Bechwana White cultivar inhibited growth of Staphylococcus aureus and Enterococcus faecalis at 2.5 mg/ml and Bacillus cereus, B. subtilis and Enterobacter cloacae at 5.0 mg/ml. Ethanol extracts of the same cultivar showed antibacterial activity against E. faecalis and E. cloacae at 5.0 mg/ml. This study represents the first report on the natural occurrence of fumonisins on cowpea seed and the potential of F. proliferatum isolates from cowpea seed to produce fumonisins. The phytotoxic effects of FB1 on cowpea seeds as well as the antimicrobial potential of cowpea leaf extracts were demonstrated for the first time. / Thesis (PhD)--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted
163

Enhancing the capacity of seeds as turbidity removal agents in water treatment. : A Minor Field Study. / Fröproteiner som fällningsmedel för minskning av turbiditet vid vattenrening.

Blix, Annika January 2011 (has links)
The aim of this master’s thesis was to investigate if defattening of Parkinsonia aculeata (in swahili “mkeketa”) and Vigna unguiculata (in swahili “choroko”) would enhance the capacity of the seed’s properties in removing suspended particles from surface water. The seeds are used in local traditional treatment of drinking water in Tanzania. The aim was also to investigate the possibility to reduce high concentrations of fluoride with the seeds. The seeds contain proteins that act as coagulants. Coagulated particulate matter can be flocculated and separated from the water. A purification of the coagulants by defattening was expected to enhance the coagulating capacity. Experiments were conducted in jar-tests with dosages of coagulant solutions of undefattening and defattened seed solutions and alum (aluminium sulphate). The experiments showed that both Parkinsonia aculeata and Vigna unguiculata seeds can compete with alum in drinking water treatment of surface water, reaching the same or better final results in turbidity removal. Both seeds also produce less sludge volumes than alum and functions in turbidity removal together with alum. The seeds may be used as coagulant aids to reduce the usage of chemicals and sludge production. They were not able to clarify turbid waste water and did not reduce high concentrations of fluoride in groundwater. Further, the turbidity-removal capacity of the coagulants had reduced capacities in water with low pH-values.
164

Levantamento de Nemat?ides Associados ? Cultura do Caupi no Estado do Rio de Janeiro e Avalia??o de Linhagens de Caupi ? Infec??o por Meloidogyne incognita ra?a 1, M. javanica e Rotylenchulus reniformis. / Levantamento de Nemat?ides Associados ? Cultura do Caupi no Estado do Rio de Janeiro e Avalia??o de Linhagens de Caupi ? Infec??o por Meloidogyne incognita ra?a 1, M. javanica e Rotylenchulus reniformis. / Survey of Nematodes Associated with Cowpea Crop in the State of Rio de Janeiro and Evaluation of Cowpea Lines to Infection by Meloidogyne incognita ra?a 1, M. javanica and R. reniformis. / Survey of Nematodes Associated with Cowpea Crop in the State of Rio de Janeiro and Evaluation of Cowpea Lines to Infection by Meloidogyne incognita ra?a 1, M. javanica and R. reniformis.

Nascimento, Rhadyson Reinaldo Silva do 03 September 2008 (has links)
Made available in DSpace on 2016-04-28T14:57:35Z (GMT). No. of bitstreams: 1 2008 - Rhadyson Reinaldo Silva do Nascimento.pdf: 1733739 bytes, checksum: b1070eca267f85de92499d2e245add23 (MD5) Previous issue date: 2008-09-03 / Cowpea (Vigna unguiculata L. Walp.) is a very important crop in Brazil, mainly in the north and northeast regions of the country, and is gaining importance in the southeast region. In this crop, nematodes are a great threat, because they can cause yield decrease. Information about these pathogens is very few. In a first approach this work aimed at surveying for the occurrence of plant parasitic nematodes that are associated to cowpea in the State of Rio de Janeiro, through sampling achieved in some locations of Nova Igua?u, Mag?, Serop?dica, S?o Francisco de Itabapoana, and Itagua?, where cowpea is grown cultivated. Eight genera of plant parasitic nematodes we found, besides others, that are free leving that were not identified. At the level of species M. incognita and Rotylenchulus reniformis were identified. Nematode identification was done on the bases of morphometric characteristics descriptive keys M. incognita by juvenile (J2 ) and males characteristics and perineal female patterns and esterases profile. In this step, surveys were carried out aiming at the detection of esterases activity for a population of R. reniformis. Protocols routinely used in isoezymes analysis were tested and showed negative results. On the other hand, assays using PCR tubes with the objective to identify esterase activity demonstrated that it was positive for R. reniformis. Modifications in the common protocols, such as changes in buffer solution at the and steps of the procedures, as well as adjusting pH near to neutrality enabled the establishment of a three band pattern of esterase in the studied populations of R. reniformis. In another phase of this work, six cowpea lines in advanced phase of improvement from determining their behavior when inoculated with M. incognita race 1, M. javanica and R. reniformis. The tomato cv. TRural was used as susceptible pattern. The experiments were carried out under greenhouse condition, using 5,000 eggs + juveniles per experimental plots, as inoculum level; for Meloidogyne species evaluation was done 50 days after nematodes inoculations based in the following parameters: galls indices (IG), egg mass indices (IMO) and reproductions rate (FR), calculated by the relation Pf/Pi ( Pf = final populations and Pi= start population). Among the tested lines, five of then RJ 04-04, RJ 04-08, RJ 04-26, RJ 04-48 and RJ 04-65 showed to be highly resistant and line RJ 04-29 was moderately resistant to M. incognita race 1. In the case of M. javanica all lines were highly susceptible. For evaluation of R. reniformis it was used as inoculum and "pure" population multiplied vegetation home. It was inoculated 5000 eggs and juvenile of males and of immature females. As parameter for evaluation of the resistance of the cowpea lineages to the nematode, the reproduction factor was used (Fr) appraised to the 45 days after inoculation. It was verified that all of the tested lineages were considered susceptible; to cultivate "Costel?o" included as witness showed equal behavior. / O caupi (Vigna unguiculata Walp.) ? uma cultura de grande import?ncia para o pa?s, principalmente na regi?o Norte e Nordeste e vem ganhando espa?o na regi?o Sudeste. Nesta cultura, os nemat?ides possuem influ?ncia significativa, chegando ao ponto de limitar a sua produ??o. As informa??es sobre estes pat?genos no Estado do Rio de Janeiro s?o escassas. Assim, numa primeira etapa, este trabalho teve por objetivo fazer um levantamento de nemat?ides fitoparasitas associados a cultura do caupi no Estado do Rio de Janeiro, por meio de coletas realizadas em alguns munic?pios produtores de caupi cultura. Foram encontrados, um total de oito g?neros de nemat?ides fitoparasitas, al?m de outros de vida livre n?o identificados. Em n?vel de esp?cie foram identificadas Meloidogyne incognita ra?a 2 e Rotylenchulus reniformis. As identifica??es foram efetuadas a partir de caracter?sticas morfom?tricas e aux?lio de chaves descritivas. M. incognita foi identificada pelas caracter?sticas dos juvenis (J2) e de machos, configura??o do modelo perineal das f?meas e perfil de esterases. Foram realizados ensaios com o objetivo de detec??o de atividade de esterase, para uma popula??o do nemat?ide R. reniformis. Para tanto foram testados protocolos rotineiramente usados em an?lises isoenzim?ticas, que apresentaram resultados negativos. Entretanto, ensaios montados em microtubos para PCR, evidenciaram atividade ester?sica para R. reniformis. Finalmente, modifica??es nos protocolos usuais como mudan?as na concentra??o da solu??o tamp?o de revela??o, assim como a fixa??o do pH da mesma pr?ximo a neutralidade, permitiram estabelecer um padr?o com tr?s bandas distintas de esterases na popula??o de R. reniformis estudada. Em uma segunda etapa deste trabalho, seis linhagens de caupi em fase avan?ada de melhoramento para resist?ncia a viroses, foram testadas visando determinar a rea??o das mesmas quando inoculadas com M. incognita ra?a 1, ou M. javanica, ou R. reniformis. A cultivar de tomate TRural foi usada como testemunha suscet?vel nos testes com as duas esp?cies de nemat?ide das galhas radiculares. Os experimentos foram realizados em casa de vegeta??o e usou-se uma carga de in?culo de 5000 ovos + juvenis/repeti??o; para as esp?cies de Meloidogyne a avalia??o ocorreu 50 dias ap?s inocula??o e os par?metros usados foram: ?ndice de galhas (IG), ?ndice de massa de ovos (IMO) e fator de reprodu??o (Fr) calculado pela rela??o Pf/Pi (Pf = popula??o final e Pi = popula??o inicial). Das cinco linhagens testadas, RJ 04-04, RJ 04-08, RJ 04-26, RJ 04-48 e RJ 04-65 comportaram-se como altamente resistentes e a linhagem RJ 04-29 como moderadamente resistente para M. incognita ra?a1. Enquanto que, para M. javanica, todas as linhagem foram altamente suscet?veis. Para avalia??o de R. reniformis foi usado como in?culo uma popula??o pura multiplicada em casa de vegeta??o. Inoculou-se 5000 ovos e/ ou juvenis de machos e de f?meas imaturas. Como par?metro para avalia??o da resist?ncia das linhagens de caupi ao nemat?ide, foi usado o fator de reprodu??o (Fr) avaliado aos 45 dias ap?s inocula??o. Verificou-se que todas as linhagens testadas foram consideradas suscet?veis; a cultivar Costel?o inclu?da como testemunha mostrou igual comportamento.
165

Bases para o cultivo org?nico de feij?o-caupi [Vigna unguiculata L. (Walp.)] no estado do Rio de Janeiro. / Organic farming systems for cowpea [Vigna unguiculata L. (Walp.)] in the state of Rio de Janeiro.

Guedes, Rejane Escrivani 25 March 2008 (has links)
Made available in DSpace on 2016-04-28T14:59:00Z (GMT). No. of bitstreams: 1 Rejane Escrivani Guedes.pdf: 2537678 bytes, checksum: fa415f1591e33c3b7c367223fc134c67 (MD5) Previous issue date: 2008-03-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Cowpea genotypes submitted to organic management were evaluated for grain yield and green manure, as well as intercropped with corn, under field conditions of Serop?dica, state of Rio de Janeiro. In the year of 2005, 53 cowpea genotypes were compared at the Integrated Agroecology Produc tion System ( SIPA Km 47 Agroecologic Farm) relating to qualitative and quantitative agronomic traits. Data were treated by following univariate and multivariate statistical analysis. Significant differences were detected with respect to all the evaluated parameters. Genotypes EES-02, EES-08, EES-26, EES47, Feij?o-Caupi and Feij?o Mau? showed favourable attributes for immature (=green) grain yield. They presented determinate growth habit with moderate branchding and flowering stage up to 45 days after sowing, only differing by pod and grain colors. Univariete analysis demonstrated high variability among cowpea genotypes. However, multivariate analysis was more efficient to joint selected agronomic traits for identification of genotyp ic groups, which can be important in cowpea breeding programs. Cowpea and corn intercrops also submitted to organic cultivation were evaluated by means of two field experiments carried out at SIPA. In Experiment 1, the cowpea cultivars Mau?, BRS Mil?nio and Olho de Peixe were intercropped with corn (cv. AG-1051) to function as green manures. A randomized blocks design was employed in factorial 2x3 scheme (two corn plant spacing x three cowpea cultivars). In Experiment 2, Mau? cowpea and AG-1051 corn were intercropped for harvesting immature (=green) grains and spikes, respectively. Treatments consisted of four time intervals between cowpea and corn sowing. As for Experiment 1, corn planted in double rows favoured cowpea aboveground biomass production, probably due to a greater amount of light admitted into the system. Results from Experiments 2 indicated that intercrop with cowpea did not decrease corn yield which reached averages of 9,5 and 5,9 Mg ha-1 of ears with and without straw, respectively. Regarding cowpea grain yield of Mau? cultivar its single crop was superior to the intercrops exceeding 1400 kg ha-1. Treatment corresponding to 21 days of interval between cowpea and corn sowing differed from the other types of intecrops, with yield attaining 978,75 ka ka-1. It is concluded that the intercropping system can se adopted in the region without risks of lowering corn yield due to competition, being three weeks (21 days) the most adequate time interval between sowing. / Foi avaliado, em sistema org?nico de produ??o, o desempenho de gen?tipos de feij?o-caupi com potencial para produ??o de gr?os verdes e aduba??o verde, e em cons?rcios com o milho, nas condi??es da Baixada Fluminense, munic?pio de Serop?dica, estado do Rio de Janeiro. No ano de 2005, em ?rea do SIPA, (Sistema Integrado de Produ??o Agroecol?gica Fazendinha Agroecol?gica Km. 47 ), foram avaliados 53 gen?tipos de feij?o-caupi, segundo caracter?sticas fitot?cnicas qualitativas e quantitativas. Os dados foram submetidos a an?lise de vari?ncia univariada e a an?lise multivariada. Houve diferen?a significativa para todos os par?metros avaliados. Os gen?tipos EES-02, EES-08, EES-26, EES-47, Feij?o-Caupi e Feij?o Mau? reuniram caracter?sticas mais adequadas para colheita de gr?os verdes, apresentando porte semi-ramador, h?bito de crescimento determinado, com florescimento at? 45 dias ap?s semeadura, diferindo apenas pela colora??o da vagem e do gr?o. Os resultados da an?lise univariada demonstraram alta variabilidade entre os gen?tipos. Por?m, para o caso de se reunir v?rios atributos fitot?cnicos, constituindo grupos de gen?tipos, a an?lise multivariada se mostrou mais eficiente e pode ser de valia para o melhoramento do feij?o-caupi. Foi avaliado, ainda, o desempenho agron?mico dos cons?rcios do milho com o feij?o-caupi submetidos ao manejo org?nico, atrav?s de dois experimentos conduzidos no SIPA. No Experimento 1, avaliou-se o desempenho de tr?s cultivares de feij?o-caupi para aduba??o verde do milho (cv. AG-1501) em cons?rcios simult?neos. As cultivares de feij?o-caupi Mau?, BRS Mil?nio e Olho de Peixe foram utilizadas, adotando-se delineamento de blocos ao acaso, em esquema fatorial 2 x 3 (dois espa?amentos de milho e tr?s cultivares de feij?ocaupi). No Experimento 2, avaliou-se o cons?rcio entre feij?o-caupi (cv. Mau?) e milho (cv. AG-1051) para colheitas de gr?os verdes e de espigas verdes, respectivamente. Os tratamentos constaram de quatro intervalos entre as semeaduras de feij?o-caupi e de milho. No Experimento 1, o espa?amento do milho em fileiras duplas favoreceu a produ??o de biomassa a?rea fresca de feij?o-caupi, muito provavelmente pela maior entrada de luz no sistema. Os resultados do Experimento 2 indicaram que o cons?rcio n?o interferiu na produtividade do milho, colhendo-se, em m?dia, 9,5 e 5,9 Mg ha-1 de espigas verdes empalhadas e desempalhadas, respectivamente. Com rela??o ? produ??o de gr?os verdes da cv. Mau? de feij?o-caupi, o monocultivo superou os cons?rcios com o milho, ultrapassando 1400 kg ha-1. O cons?rcio correspondente a 21 DAM (dias antes do milho) diferiu dos demais tipos de cons?rcio, sendo superior, em produ??o, que atingiu 978,75 kg ha-1. Concluiu-se que o sistema de cons?rcio com o feij?o-caupi pode ser adotado na regi?o sem risco de perdas na produtividade do milho por efeito de competi??o, sendo de tr?s semanas (21 DAM) o intervalo mais adequado entre as semeaduras.
166

Ecofisiologia de feijão-caupi submetido a deficiência hídrica nos sistemas de plantio direto e convencional / Cowpea ecophysiology subjected to water stress in no-tillage and conventional

Freitas, Rômulo Magno Oliveira de 07 July 2015 (has links)
Made available in DSpace on 2016-08-12T19:18:34Z (GMT). No. of bitstreams: 1 RomuloMOF_TESE.pdf: 1235930 bytes, checksum: d0668b69077e4b615b5b9b7e4cd858f6 (MD5) Previous issue date: 2015-07-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The cowpea crop has great importance for the Brazilian Northeast, especially for the poorest population. One of the major problems encountered for this crop is drought stress caused by erratic rainfall, coupled with the high temperatures common in this region. The no-tillage system has features, such as reduction of soil water evaporation, higher water retention and lower soil temperature fluctuations, and can be a way to minimize the water stress in a cowpea crop. Two experiments were carried out at the experimental garden in the Departamento de Ciências Vegetais of the Universidade Federal Rural do Semi-Árido (UFERSA), in Mossoró city, RN, with the aim of evaluating the use and use efficiency of water, and the ecophysiological traits of cowpea plants under water shortage in tillage and no-till cropping systems. The first experiment was conducted in a randomized complete blocks design with subsampling and four replications. The treatments were the two cropping systems (tillage and no-till), and the subsamples were the six periods of irrigation suspension (2; 6; 10; 14; 18 e 22 days), applied at the beginning of the flowering stage. The plants parts dry mass and the leaf area 64 days after sowing (DAS), and the grain production, water use and water use efficiency at that 70 DAS were evaluated. For the second experiment, it was used a randomized complete blocks design with subsampling and sub-subsampling, with four replications. The treatments were the cropping systems (tillage and no-till), and the subsamples were three water availability conditions (no shortage, moderate shortage and severe shortage), and the sub-subsampling were the evaluation periods. Plants dry mass, leaf areas, photosynthesis, stomatal conductance, transpiration, lowest leaf CO2 internal concentration and leaf water potential were evaluated. In the first experiment, it was observed that the no-till system is promising for the cowpea crop, with better grain production and better water use efficiency. In this system, the cowpea cultivation was possible even under a moderate water shortage. Prolonged water shortage periods did affect the dry mass accumulation, grain yield and water use efficiency. In the second experiment, the water shortage affected all the studied variables, with the exception of the leaves water potential. The cowpea fully recovered all physiological traits after moderate and severe water shortage. Stomatal closure was the main mechanism of resistance to water shortage, and the cowpea may be considered as a water-saving species. The cropping system did not affect the photosynthesis rates. The plants had more dry weight and leaf areas at the no-till system / A cultura do feijão-caupi possui grande importância para a região Nordeste, principalmente para a população mais carente. Um dos grandes problemas encontrados para essa cultura é o estresse hídrico, provocado pela irregularidade das chuvas, aliado a altas temperaturas, comuns a esta região. O sistema de plantio direto possui características como redução da evaporação da água do solo, maior retenção do solo e menores oscilações da temperatura, e pode ser uma forma de minimizar o efeito do estresse hídrico para a cultura do feijão-caupi. Dois experimentos foram conduzidos na horta didática do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido (UFERSA), no município de Mossoró-RN, com o objetivo de avaliar o consumo, e eficiência de uso da água, bem como as respostas ecofisiológicas de feijão-caupi sob estresse hídrico nos sistemas de plantio direto e convencional. O primeiro experimento foi realizado no delineamento experimental em blocos casualizados completos, no esquema de parcelas subdivididas, com quatro repetições. Nas parcelas, foram avaliados dois sistemas de plantio (convencional e direto) e nas subparcelas, seis períodos de suspensão da irrigação (2; 6; 10; 14; 18 e 22 dias) aplicados no início do período reprodutivo. Foram avaliadas a biomassa das partes das plantas e a área foliar, aos 64 dias após a semeadura (DAS) e o rendimento de grãos, consumo de água e eficiência de uso da água, aos 70 DAS. No segundo experimento, utilizou-se o delineamento experimental em blocos casualizados completos, no esquema de parcelas subsubdivididas, com quatro repetições. Nas parcelas, foram avaliados dois sistemas de plantio (direto e convencional), nas subparcelas, três condições hídricas (sem estresse, estresse moderado e estresse severo) e nas subsubparcelas, períodos de avaliação. Foram determinados: área foliar, matéria seca total, fotossíntese, condutância estomática, transpiração, concentração interna de CO2 e potencial hídrico foliar. No primeiro experimento, constatou-se que o sistema de plantio direto foi promissor para cultura do feijão-caupi, apresentando maior rendimento de grãos e maior eficiência de uso da água. Nesse sistema de plantio, foi possível o cultivo de feijão-caupi, sem perdas, mesmo com períodos de veranico moderados. Veranicos prolongados afetaram negativamente o acúmulo de biomassa, rendimento de grãos e eficiência de uso da água. No segundo experimento, o estresse hídrico afetou todas as variáveis avaliadas, com exceção do potencial hídrico foliar. O feijão-caupi apresentou recuperação de todas as características fisiológicas após estresse hídrico moderado e severo. O fechamento estomático foi o principal mecanismo de resistência à seca, sendo o feijão-caupi uma espécie conservadora. Os sistemas de plantio não afetaram as taxas de fotossíntese. O sistema de plantio direto promoveu maior acúmulo de biomassa e de área foliar
167

CaracterizaÃÃo de dois cultivares de Vigna unguiculata em reposta a seca combinada ou nÃo com ozÃnio: regulaÃÃo de proteÃnas membranares (AOX, pUCP E PTOX) / Characterization of two varieties of Vigna unguiculata in response the drought or not combined with ozone: adjustment membrane proteins (AOX, pUCP and PTOX)

Francisco Yuri Maia de Sousa 23 November 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A FotossÃntese e a respiraÃÃo sÃo bem conhecidos como sendo responsÃveis pela produÃÃo de energia no interior das cÃlulas de plantas. Acoplados à estes processos bioenergÃticos, a transferÃncia de elÃtrons que ocorre nas membranas do cloroplasto e mitocÃndria, tambÃm sÃo considerados com tendo potencial de produÃÃo de ROS. PossÃveis interaÃÃes no funcionamento dessas organelas permanecem pouco conhecidas, especialmente em resposta a condiÃÃes de estresse. Sob estas condiÃÃes, sugere-se que as vias de transferÃncia de elÃtrons ligadas à AOX, à pUCP ou à PTOX poderia limitar a formaÃÃo de ROS reduzindo assim danos oxidativos Ãs organelas celulares. Em nosso trabalho, foram selecionadas duas cultivares de Vigna unguiculata, inicialmente caracterizados como sensÃvel (cv 1183) ou tolerante (cv EPACE1) à seca. Sob condiÃÃes experimentais, as duas cultivares nÃo apresentaram diferenÃas significativas na sensibilidade à seca. Entretanto o cultivar EAPCE1 foi mais tolerante ao ozÃnio com base no desenvolvimento de necrose e de vÃrios parÃmetros fisiolÃgicos (ϕPSII) e bioquÃmicos (teor de glutationa). Para os perfis de expressÃo de genes que codificam AOX, PUCP e PTOX duas respostas foram claramente identificadas no cultivar EPACE1. Em um tempo curto, a expressÃo destas proteÃnas à geralmente estimulada. Em um perÃodo mais longo (14 dias), a resposta à diferente, dependendo da tipo de estresse. Sob o ozÃnio, um aumento da expressÃo das proteÃnas mitocondriais à mantida enquanto o gene que codifica para a PTOX à sub-regulada. Sob seca a proteÃna desacopladora do plastÃdio (PTOX) à superexpressa. Sob condiÃÃes de combinaÃÃo stress, seca combinada com ozÃnio, o efeito da seca sobre o fluxo de ozÃnio nas folhas nÃo foi alterado, e os genes VuPTOX e VuUCP1b sÃo super-expressos depois de 3 e 7 dias de stress. Este aumento da expressÃo, jà observado em resposta à seca por aplicada separadamente poderia desempenhar um papel na prevenÃÃo da formaÃÃo de ROS tanto em mitocÃndrias e cloroplastos prevenindo assim os danos causados pelo ozÃnio. / Possible interactions between chloroplast and mitochondria remain poorly known, particularly in response to stress conditions. Under these conditions, it is suggested that the electron transfer pathways linked to AOX or pUCP (mitochondrial uncoupling proteins) and PTOX (plastidial uncoupling protein) could limit the formation of ROS to reduce oxidative damage in cellular organelles. In our work, we selected two cultivars of Vigna unguiculata, cv 1183 and cv EPACE. Under our experimental conditions, both cultivars showed no real differences in sensitivity to drought. However cv EPACE was more tolerant to O3 based on the development of necrosis and several physiological parameters (Fv/Fm, ϕPSII) and biochemical (glutathione content). For the expression profiles of genes encoding AOX, PUCP and PTOX two responses were clearly identified in the cultivar EPACE. On a shortterm, expression of these proteins is generally stimulated. On a longer term (14 days), the answer differs depending on the treatment. Under O3, the strongest expression of mitochondrial proteins is maintained while the gene encoding the PTOX is own-regulated. Under drought only the plastid protein (PTOX) is upregulated. Under conditions of stress combination, drought has little effect on the influx of O3 in the leaves, and the VuPTOX and VuUCP1b genes are up-regulated after 3 and 7 days of stress. This ver-regulation, already observed in response to drought alone could play a role in preventing the formation of ROS in both mitochondria and chloroplasts.
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Aproveitamento de resÃduos de caranguejo uÃÃ gerados pelas barracas da praia do futuro como fonte alternativa de adubo orgÃnico em cultura de feijÃo caupi. / Exploitation of crab residues uÃÃ generated by the tents of the beach of the future as alternative organic seasoning source in beans culture caupi.

Francisco Josà Freire de AraÃjo 26 June 2007 (has links)
nÃo hà / O atual gerenciamento dos ResÃduos SÃlidos Urbanos (RSU) na maioria das cidades brasileiras vem se mostrando pouco eficaz para o atendimento das populaÃÃes, tanto pela explosÃo demogrÃfica ocorrida nas Ãltimas dÃcadas como pelo seu estilo de vida consumista. A produÃÃo massiva de resÃduos sÃlidos, lÃquidos e gasosos tambÃm està ligada diretamente à tecnologia empregada no beneficiamento dos produtos extraÃdos da natureza, os quais, na maioria das vezes, sÃo difÃceis de serem reabsorvidos pelos ecossistemas. Dessa maneira, a limpeza urbana assume um importante papel dentre as necessidades da sociedade brasileira, adquirindo importÃncia sanitÃria, econÃmico-financeira, social e estÃtica. Estudos realizados quanto ao aproveitamento e reciclagem dos lixos revelaram suas potencialidades e uma excelente alternativa como destino final de muitos resÃduos urbanos. O presente estudo ressalta a problemÃtica dos RSU, tendo como objetivo propor uma alternativa para reduÃÃo de resÃduos orgÃnicos de caranguejo uÃa gerados pelas barracas de praia, localizadas na Praia do Futuro, na cidade de Fortaleza, bem como sugerir, aos demais estabelecimentos comerciais que produzem o mesmo tipo de resÃduo, transformÃ-los em fertilizantes orgÃnicos. A pesquisa tambÃm procurou verificar a viabilidade do produto gerado dos resÃduos de caranguejo como uma fonte nutricional alternativa para uma cultura de feijÃo caupi. A escolha dessa cultura se deve primeiramente pela sua relevÃncia para populaÃÃo e por oferecer uma rÃpida resposta, sendo uma cultura de ciclo curto. AlÃm de estudar a composiÃÃo do lixo gerado por esses estabelecimentos, a pesquisa tambÃm buscou analisar sua composiÃÃo quÃmica, seu rendimento e buscar dados de produtividade como altura da planta, nÃmero de vagens, tamanho das vagens, peso das vagens, nÃmero de sementes por vagens e peso de cem sementes. Para este estudo foram testados vinte e dois tratamentos com quatro repetiÃÃes, os quais variavam quanto Ãs proporÃÃes de adubo de caranguejo e fertilizante quÃmico de ambos para que fossem verificadas suas respostas. O percentual de matÃria orgÃnica reciclÃvel desse lixo estudado à de aproximadamente 87,34%, entretanto, os resÃduos de caranguejo contribuem com 52% desses rejeitos. O rendimento desse material à de aproximadamente 24%. Alguns parÃmetros analisados como nitrogÃnio, fÃsforo, cÃlcio e magnÃsio ganharam destaque devido seus valores percentuais, encontrados nesse produto orgÃnico, variarem de duas a quatro vezes mais quando os mesmos sÃo observados numa amostra de esterco bovino. Os dados relativos à produtividade revelaram que os tratamentos que proporcionaram os melhores resultados tinham em comum a presenÃa da farinha de caranguejo, mostrando que a adiÃÃo desse composto orgÃnico melhora as respostas quanto aos parÃmetros de produtividade, implicando na reduÃÃo da quantidade de fertilizantes quÃmicos no solo, no aumento da economia para o produtor e um destino adequado para os resÃduos sÃlidos orgÃnicos gerados. / The current management of the Urban Solids Residuals (URS) in most Brazilian cities have been considered to be slightly inefficient for the demand of the population, due to the rapid growth of the population in the last few decades and also because of their consuming lifestyle. The massive production of solid, liquids and gas residuals is also directly linked with the technology employed to benefit products extracted from nature, which most cases are difficult to be reabsorbed by the ecosystems. In this way, the urban cleanliness assumes an important role among the needs of the Brazilian society; gaining sanitary, economic, social and aesthetic importance. Studies conducted regarding the positive outcomes and the recycling of rubbish have shown its potentialities and an excellent alternative to the final disposal of many urban residuals. The current study highlights the problems and concerns with the URS, and suggests an alternative for the reduction of crabâs organic residuals generated by the restaurants at Futuroâs Beach in Fortaleza. In addition, the present study also proposes to other commercial establishments that produce such residuals, opportunity to transform them in organic fertilizers. The research aims to verify the viability for a better use of crabâs residuals generated by the restaurants at Futuroâs Beach as an alternative organic compost, working as a nutritional resource for a culture of Caupi beans. The choice for this culture is primarily due to its relevance to the wide population and also for being able to offer a quick response, as it is a culture of short cycle. Further to the study of the composition of the rubbish generated by such establishments, the research also aimed to analyse its chemical composition, its income and to look for productivity items such as plantâs height, number and size of string beans, weight of string beans, number of seeds per string beans, and the weight of a hundred seeds. For the purpose of this study, twenty two treatments, with four repetitions, which varied between the proportions of crab compost and chemical fertilizers in both of them were used in order to verify the results. The percentage of recyclable organic contents of this rubbish studied is about 87, 34%. However, crabâs residuals contributed with 52%. The income of this material is around 24%. Some parameters analysed like nitrogen, phosphorus, potassium, calcium and magnesium stood out due to its percentage values, found in this organic product, vary between 3 and 4 times more than those found in a sample of bovine compost. The data related to the productivity revealed that the treatments which obtained the best results had in common the presence of crabâs flour. This shows that by adding this organic compost enhances productivity parameters, which has a direct impact in the reduction of the amounts of chemical fertilizers used in the soil, a financial saving for the farmer and an adequate means for the organic solid residuals generated.
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Irrigation of cowpea with saline water at different growth stages and their effects on the plant and soil / IrrigaÃÃo do feijÃo-de-corda com Ãgua salina em diferentes estÃdios de desenvolvimento e seus efeitos na planta e no solo.

AntÃnia Leila Rocha Neves 11 April 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A sensibilidade à salinidade varia com o estÃdio de desenvolvimento da cultura. O feijÃo-de-corda [Vigna unguiculata (L.) Walp.] constitui uma das principais culturas, em diversas regiÃes semi-Ãridas do mundo. Avaliou-se o efeito da irrigaÃÃo com Ãgua salina, aplicada em diferentes estÃdios de desenvolvimento de plantas de feijÃo-de-corda. O experimento foi conduzido no campo, e obedeceu ao delineamento em blocos ao acaso, com cinco tratamentos (T1, T2, T3, T4 e T5) e cinco repetiÃÃes. O feijÃo-de-corda foi cultivado no espaÃamento de 0,8 m entre linhas e 0,3 m entre plantas, com duas plantas por cova. Os tratamentos utilizados foram: T1 - plantas irrigadas com Ãgua do poÃo (CEa de 0,8 dS m-1) durante todo o ciclo; T2 - Ãgua salina com CEa de 5,0 dS m-1, com aplicaÃÃo iniciada apÃs a germinaÃÃo e permanecendo atà o final do ciclo; T3 - Ãgua salina com CEa de 5,0 dS m-1, da semeadura atà 22 dias apÃs o plantio (DAP), correspondendo Ãs fases de germinaÃÃo e crescimento inicial, e Ãgua do poÃo no restante do ciclo; T4 - Ãgua salina com CEa de 5,0 dS m-1, aplicada de 23 a 42 DAP (fase de intenso crescimento vegetativo atà a prÃ-floraÃÃo), e Ãgua do poÃo nas demais fases do ciclo; T5 - Ãgua do poÃo da semeadura atà 42 DAP e Ãgua salina (CEa de 5,0 dS m- 1) aplicada a partir dos 43 DAP (floraÃÃo e frutificaÃÃo). Foram avaliadas a cobertura vegetal do solo, crescimento vegetativo, fotossÃntese, transpiraÃÃo, condutÃncia estomÃtica, produtividade, partiÃÃo de matÃria seca, os teores, os totais extraÃdos e a distribuiÃÃo dos nutrientes na planta, a eficiÃncia nutricional, eficiÃncia no uso da Ãgua e o acÃmulo de sais no solo. A irrigaÃÃo com a combinaÃÃo de Ãgua do poÃo com Ãgua salina reduziu o acÃmulo de sais no solo, em relaÃÃo ao T2. O T2 reduziu as taxas de fotossÃntese e transpiraÃÃo, em relaÃÃo ao T1. O T3 provocou reduÃÃo das trocas gasosas somente na primeira mediÃÃo, enquanto, que similar aplicaÃÃo nos outros estÃdios (T4 e T5) nÃo provocou reduÃÃes significativas nas trocas gasosas das plantas. O T2 inibiu o crescimento vegetativo da planta, enquanto o T3 provocou retardo no desenvolvimento da planta. Os tratamentos T2 e T3 provocaram reduÃÃes significativas no nÃmero de vagens e na produÃÃo de sementes por planta, em relaÃÃo aos demais tratamentos. Por outro lado, os tratamentos T4 e T5 nÃo afetaram o crescimento e a produtividade da cultura, sendo que o T4 causou aceleraÃÃo no ciclo reprodutivo da cultura. Os minerais foram extraÃdos pelo feijÃo-de-corda na seguinte ordem decrescente: N > K > Cl > Ca > Na > P > Fe > Zn > Mn > Cu, no entanto, o T2 reduziu a extraÃÃo da maioria dos elementos analisados, com exceÃÃo do Na e Cl. Os minerais Na, Cl, K, Ca, Fe e Mn permaneceram preferencialmente nas partes vegetativas enquanto N e P foram exportados em maiores proporÃÃes pelos frutos. O T3 reduziu a eficiÃncia de utilizaÃÃo da maioria dos nutrientes. O T2 reduziu a eficiÃncia agronÃmica de utilizaÃÃo de N, P e K, entretanto nÃo afetou a eficiÃncia de utilizaÃÃo dos nutrientes extraÃdos pelas plantas. / The sensitivity of crops to salinity often changes from one growth stage to another. Cowpea [Vigna unguiculata (L.) Walp.] is an important crop specie cultivated in different semi-arid regions of the world. The objective of this work was to evaluate the effect of the irrigation with saline water, applied at different growth development stages of cowpea. The experiment was set up in the field, during the dry season. A completely randomized block design, with five treatments (T1, T2, T3, T4 and T5) and five repetitions, was adopted. The distance between lines and plants were 0.8 m and 0.3 m, respectively, with two plants per hole. The treatments studied were: T1 - Groundwater with electrical conductivity (ECw) of 0.8 dS m-1 during the whole crop cycle; T2 - Saline water (ECw = 5.0 dS m-1) during the whole crop cycle, starting after germination; T3 - Saline water (ECw = 5.0 dS m-1) from sowing until the 22th day after sowing (germination and initial growth) and groundwater in remaining stages of the crop cycle; T4 - Saline water (ECw = 5.0 dS m-1) from the 23th to the 42nd day after germination (intense growth and pre-flowering), and groundwater irrigation for the remaining growth stages. T5 - Groundwater from sowing to the 42nd day after sowing and saline water (ECw = 5.0 dS m-1) during flowering and pod-filling stages. Soil coverage, gas exchange, vegetative growth and crop yield were measured. The mineral concentration and quantity of nutrient removed from the soil, as well as the nutrient use efficiency and salt accumulation in soil were also determined. The irrigation with combination of groundwater and saline water reduced the salt accumulation in soil, in relation to continuous use of saline water. The continuous application of water with ECw of 5.0 dS m-1 (T2) reduced the rates of photosynthesis and transpiration, in relation to the well water (T1). Plants of the treatment 3 showed reduction in gas exchanges only in the first measurement, while the saline water application in other growth stages (T 4 and T5) did not provoke significant reductions in leaf in the gas exchanges of the plants. It was found that the continuous use of saline water inhibits plant growth, while the irrigation with saline water during germination and initial growth causes retardation in plant development. For treatments 2 and 3, reduction in the number of pods and in seed production was verified. Irrigation with saline water from the 23rd to the 42nd day (T4) and from the 43rd to the 63rd (T5) day after sowing did not affect reproductive and vegetative growth, but the saline water application in the pre-flowering (T4) caused anticipation of reproductive cycle. Cowpea plants removed the minerals analyzed in the following decreasing sequence: N > K > Cl > Ca > Na > P > Fe > Zn > Mn > Cu, but the continuous use of saline water (T2) reduced the total extracted for the most nutrients, except for Na e Cl. The minerals Na, Cl, K, Ca, Fe and Mn were distributed preferentially to vegetative plant parts, while the most of N and P were exported in the pods. The irrigation with saline water during germination and initial growth stage (T3) reduced the mineral use efficiency of most of analyzed nutrients. The continuous application of saline water (T2) reduced the agronomic efficiency of the fertilizer application (N, P and K), but it did not affect the nutrient use efficiency by the plants.
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The role of indigenously-associated abuscular mycorrhizal fungi as biofertilisers and biological disease-control agents in subsistence cultivation of morogo / Mohlapa Junior Sekoele

Sekoele, Mohlapa Junior January 2006 (has links)
The study examined interactions between morogo plants, arbuscular mycorrhizal fungi (AMF) and Fusarium species. Morogo refers to traditional leafy vegetables that, together with maize porridge, are dominant staple foods in rural areas of the Limpopo Province such as the Dikgale Demographic Surveillance Site (DDSS). Morogo plants grow either as weeds (often among maize), occur naturally in the field or are cultivated as subsistence crops by rural communities. Botanical species of morogo plants consumed in the DDSS were determined. Colonisation of morogo plant roots by AMF and Fusarium species composition in the immediate soil environment were investigated in four of eight DDSS subsistence communities, Isolated AMF were shown to belong to the genera Acaulospora and Glomus. Twelve Fusarium species were isolated from soil among which Fusariurn verticilliodes and Fusarium proliferaturn occurred predominantly. Greenhouse pot trials were conducted to examine the effect of AMF on morogo plant growth (cowpea; Mgna unguiculata) and Fusarium proliferatum levels in soil, Interaction between plants and AMF, as well as tripartite interactions of cowpea plants, AMF and Fusarium proliferatum were investigated. Non-inoculated cowpea plants served as controls for the following inoculations of cowpea in pots: (i) Fusarium proliferatum; (ii) commercial AMF from Mycoroot (PTY) Ltd. (a mixture of selected indigenous Glomus spp referred to commercial AMF for the purpose of this study); (iii) indigenous AMF obtained from DDSS soil (referred to iocal AMF for the purpose of this study); (iv) commercial AMF plus Fusarium proliferatum; (v) local AMF plus Fusariurn proliferatum. Results showed reduced root colonization by local as well as commercial AMF when Fusarium proliferatum were present. Local AMF significantly enhanced cowpea growth while commercial AMF apparently reduced the level of Fusarium proliferatum in the rhizosphere and surrounding soil. Results suggest that AMF may have potential as biological growth enhancers and bioprotective agents against Fusarium proliferatum. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.

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