Efeito de Alum?nio, Molibd?nio e de Estirpes de Riz?bio em Arachis pintoi

• Main Author: Silva, Humberto Ant?o de Sousa e
• Other Authors: Goi, Silvia Regina
• Format: Others
• Language: Portuguese
• Published: Universidade Federal Rural do Rio de Janeiro 2016
• Subjects: Arachis pintoi; leguminosa; fixa??o biol?gica de nitrog?nio; legume; biological nitrogen fixation; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA
• Online Access: https://tede.ufrrj.br/jspui/handle/tede/540

Made available in DSpace on 2016-04-28T14:58:56Z (GMT). No. of bitstreams: 1 2007-Humberto Antao de Sousa e Silva.pdf: 1812876 bytes, checksum: fc5dddb0fe3112c5b22807ccdce3e05b (MD5) Previous issue date: 2007-02-14 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior === In a modern cattle-breeding using pastures that allows a gain of weight is an essential factor. The Arachis pintoi is an option to a good alimentary diet and to the recuperation of degraded pastures, due to its potential in biological fixation of nitrogen and resistance to acid soil with high contents of aluminium. Experiments were conducted in greenhouse and growth chamber condition, in order to study the behavior of Arachis pintoi (Amarillo cv., Belmonte cv. and accession BRA-031534) in its relation to inoculation with rhizobial strains, aluminium tolerance and Mo influence. Strains CIAT-5067, CIAT-5083, CIAT-5087, BR-1432 e BR-1433 were used in inoculation experiments. In experiments with aluminium were used: a) A simple nutritive solution, initially with rates 10μM, 20μM, 40μM, 80μM and 160μM, and later 2μM, 4μM, 8μM, 16μM e 32μM, b) A complete nutritive solution with rates 20μM, 40μM, 80μM, 160μM and 320μM at Amarillo cv. and access BRA-031534 propagated by seeds and at the Amarillo and Belmonte cv. and access BRA-031534 vegetatively propagated. In the experiment with Mo, four rates of molybdenum (0g.ha-1, 50g.ha-1, 100g.ha-1 e 200g.ha-1), three levels of pH (4,0; 5,0 e 6,0) and two collection dates (49 days and 78 days) were used. The plants inoculated with CIAT strains, presented a good response to nodulation especially in relation to Belmonte cv., and with the same effectiveness of native strain. It was observed deleterious effect of nitrogen in the number of nodules. The results in simple nutritive solution had shown reduction in growth and dry mass of the root and a reduction evaluated in 27% by the relative root length between the concentration of 16μM and the control. In these experiments were observed responses to the concentration of aluminium, with appearance of mucilage and darkening of the primary root. In studies involving complete nutritional solution, Amarillo cultivar and accession BRA-031534 propagated by seeds had had reduction in the growth of the primary root and in relative length of the root in relation to the control. In the concentrations of 320μM and 160μM, a reduction of 51% and 49% respectively, in the Amarillo cultivar and access BRA-031534. It was also observed in this study with the Amarillo cultivar, roots with tip dark in the concentrations of 160μM and 320μM, and increase in the number of secondary roots from the concentration of 80μM. Pyrocatecol violet dyes seems to be promising in allowing a visualization of aluminum effects to Amarillo cultivar and accession BRA-031534. The aluminum in vegetative propagation influenced the cultivars and accession tested. Belmonte cultivar formed a higher number of adventitious roots when compared with Amarillo cv and accession BRA-031534, and with a concentration of 80μM a reduction in the adventitious roots length of the tested cultivars and access occurred. The molybdenum application promote answer in the second harvest in the pH 6,0 being obtained a larger number of nodules in the concentration of 200g.ha-1.The pH intervened in the nodulation. === Na pecu?ria moderna, o uso de pastagens que permitem um bom ganho de peso ? um fator imprescind?vel. A leguminosa Arachis pintoi apresenta-se como uma op??o tanto para uma dieta alimentar eficiente, como para recupera??o de pastagens degradadas devido ao seu potencial em fixa??o biol?gica de nitrog?nio e resist?ncia a solos ?cidos com teor elevado de alum?nio. Com a finalidade de estudar o comportamento do Arachis pintoi em rela??o ? inocula??o com estirpes de riz?bio, toler?ncia ao alum?nio e a influ?ncia do molibd?nio, foram conduzidos experimentos em condi??es de casa de vegeta??o e c?mara de crescimento. Nos experimentos de inocula??o utilizaram-se as estirpes CIAT-5067, CIAT-5083, CIAT-5087, BR-1432 e BR-1433. Nos experimentos com alum?nio foram utilizadas: a) Solu??o nutritiva simples, (10μM, 20μM, 40μM, 80μM e 160μM) e (2μM, 4μM, 8μM, 16μM e 32μM), na cultivar Amarillo. b) Solu??o nutritiva completa (20μM, 40μM, 80μM, 160μM e 320μM) na cultivar Amarillo e acesso BRA-031534 propagadas por sementes e nas cultivares Amarillo, Belmonte e acesso BRA-031534 propagadas vegetativamente. No experimento com molibd?nio, foi utilizada a cultivar Amarillo, quatro dosagens de molibd?nio (0gha-1, 50g.ha-1, 100g.ha-1 e 200g.ha-1), tr?s n?veis de pH (4,0; 5,0 e 6,0) e duas ?pocas de coleta (49 e 78 dias). Nos experimentos de sele??o de estirpes, as plantas inoculadas com as estirpes CIAT, apresentaram uma boa resposta ? nodula??o principalmente em rela??o ? cultivar Belmonte, e com a mesma efetividade que as estirpes nativas. Na cultivar Belmonte foi observado efeito delet?rio do nitrog?nio no n?mero de n?dulos por planta. Os resultados obtidos nos experimentos com Al, em solu??o nutritiva simples mostraram uma redu??o no crescimento, redu??o na massa seca da raiz e uma redu??o avaliada em 27% pelo comprimento radicular relativo entre as concentra??es de 16μM e o controle. Ocorreram nestes experimentos respostas ?s concentra??es de alum?nio, com aparecimento de mucilagem e escurecimento da raiz prim?ria. Nos estudos envolvendo solu??o nutritiva completa, as pl?ntulas da cultivar Amarillo e do acesso BRA-031534 propagadas por sementes tiveram redu??o no crescimento da raiz prim?ria e no comprimento relativo da raiz em rela??o ? testemunha. Nas concentra??es de 320μM e 160μM, observou-se uma redu??o de 51% e 49% respectivamente, na cultivar Amarillo e no acesso BRA-031534. Tamb?m foi observado na cultivar Amarillo, ra?zes com as extremidades escurecidas nas concentra??es de 160μM e 320μM e aumento no n?mero de ra?zes secund?rias a partir da concentra??o de 80μM. O corante violeta de pirocatecol parece promissor em permitir uma visualiza??o dos efeitos do alum?nio para a cultivar Amarillo e acesso BRA-031534. O alum?nio influenciou as cultivares e acesso testados com a cultivar Belmonte formando um maior n?mero de ra?zes advent?cias que a cv Amarillo e o acesso BRA-031534. A partir da concentra??o de 80μM, ocorreu uma redu??o no comprimento das ra?zes advent?cias das cultivares e acesso testados. A aplica??o de molibd?nio foi eficiente na segunda colheita no pH 6,0 sendo obtido um maior n?mero de n?dulos na concentra??o de 200g.ha-1. O pH interferiu na nodula??o.