Dispers?o de sementes de leguminosas forrageiras tropicais atrav?s das fezes de bovinos

• Main Author: Silva, Tatiana Oliveira da
• Other Authors: Almeida, Jo?o Carlos de Carvalho
• Format: Others
• Language: Portuguese
• Published: Universidade Federal Rural do Rio de Janeiro 2016
• Subjects: Seed dormancy; Germination; Dung plates; Calopo; Dorm?ncia das sementes; Placa fecal; Germina??o; Calopog?nio; Estilosantes; Kudzu tropical; Macrotiloma; Soja perene; Ci?ncias Agr?rias
• Online Access: https://tede.ufrrj.br/jspui/handle/jspui/1269

Submitted by Leticia Schettini ([e-mail]) on 2016-10-10T14:09:10Z No. of bitstreams: 1 2008 - Tatiana Oliveira da Silva.pdf: 1137658 bytes, checksum: 31af0cd49ed243269ee071f1dbf32c78 (MD5) === Made available in DSpace on 2016-10-10T14:09:10Z (GMT). No. of bitstreams: 1 2008 - Tatiana Oliveira da Silva.pdf: 1137658 bytes, checksum: 31af0cd49ed243269ee071f1dbf32c78 (MD5) Previous issue date: 2008-09-04 === Legumes have some characteristics which make them able to improve pasture productivity, since they act as green manure and prevent soil erosion by weather agents. They contribute, furthermore, to maintaining or increasing soil organic matter level, since they draw carbon and fix atmospheric Nitrogen, so mobilize and recycle nutrients, increasing microbiological soil activity. Considering the useful potential of these forage plants the seed dispersal of five legume species (Pueraria phaseoloides, Neonotonia wightii, Calopogonium mucunoides, Macrotyloma axillare and Stylosanthes cv. Mineir?o) through bovine feces in an established pasture of B. decumbens was studied in two trials. In the first one seeds mixed with concentrate were offered in the late afternoon to five crossbred (Holsten-Zebu) heifers weighing 250 kg. This experiment was carried out in a crop-pasture rotation system with five paddocks occupied for 4 days. Field evaluation were made from 12 to 30 hrs after seed ingestion, consisting in marking with sticks of different colors the sites of animal droppings in order to discriminate legume species. After 73 days of pasture vacancy was made the first evaluation in order to set the number of sprouts in the research field and Pueraria phaseoloides (puero) showed the best results, followed by Macrotyloma axillare (archer) and Calopogonium mucunoides (calopo). We accessed, in addition, the drought resistance after 266 days of pasture closure counting the survival legume plants in the pasture. The best performance for plant survival after dry season was observed in archer, followed by calopo. Concerning germination after the dry season of seeding made at the beginning of the experiment, best results were found by perennial soybean, despite its low results during the dry season. A second experiment was conducted using only archer seeds as they showed the best results concerning drought persistence. Five heifers were fed with 40 g of archer seeds; the animals were kept grazing for four days at the paddock in the crop-pasture system. At the first evaluation of this experiment we observed 215 archer plants in the research field. At the second evaluation the botanical composition analysis was made revealing the presence of 6,4% of the research area covered by archer plants (global mean of 380 plants). === As leguminosas possuem algumas caracter?sticas que contribuem para a produtividade do pasto, assim como a aduba??o verde, protegendo o solo dos agentes clim?ticos. Al?m disso, as leguminosas seq?estram o carbono e fixam o nitrog?nio atmosf?rico e, assim, apresentam potencial para manter ou elevar o teor de mat?ria org?nica, mobilizar e reciclar nutrientes e favorecer a atividade biol?gica do solo. Levando em considera??o o potencial ben?fico destas planta forrageiras objetivou-se avaliar a dispers?o de sementes de cinco leguminosas forrageiras tropicais (Pueraria phaseoloides, Neonotonia wightii, Calopogonium mucunoides, Macrotyloma axillare e Stylosanthes cv. Mineir?o) atrav?s das fezes de bovinos em pastagem j? estabelecida de Brachiaria decumbens. O primeiro experimento foi realizado em sistema de lota??o rotacionada, com 5 piquetes e 2 dias de ocupa??o. As sementes das cinco leguminosas foram oferecidas a cinco novilhas mesti?as (holand?s x zebu), pesando m?dia de 250 kg, misturadas ao concentrado no fim da tarde. Entre 12 e 30 horas ap?s a ingest?o das sementes era feita uma avalia??o a campo que consistia na marca??o com bambus de diversas cores do local das deje??es dos animais, diferenciando as esp?cies. Ap?s 73 dias de descanso foi realizada a primeira avalia??o quanto ao n?mero de plantas germinadas na ?rea experimental, sendo o Pueraria phaseoloides (kudzu tropical) a esp?cie que apresentou o melhor resultado, seguido pelo Macrotiloma axillare (macrotiloma) e Calopogonium mucunoides (calopog?nio). Ainda foi avaliada a persist?ncia ? seca, ap?s 266 dias de veda??o da pastagem, contabilizando o n?mero de plantas presentes no pasto. O melhor desempenho quanto ao n?mero m?dio de plantas ap?s a seca foi alcan?ado pelo macrotiloma, sendo seguida pelo calopog?nio. Quanto ? germina??o ap?s o per?odo de seca, das sementes implantadas no in?cio do experimento, o melhor resultado foi obtido pela soja perene, apesar da sua baixa contribui??o no per?odo de seca. O segundo experimento foi realizado apenas com sementes de macrotiloma devido ao bom resultado desta esp?cie quanto ? persist?ncia ? seca. Foram oferecidos a cinco novilhas 40g de sementes de macrotiloma; os animais permaneceram no piquete por 4 dias pastejando em sistema de lota??o rotacionada. Na primeira avalia??o deste experimento obteve-se uma m?dia de 215 plantas de macrotiloma na ?rea experimental. Na segunda avalia??o foi realizado o levantamento da composi??o bot?nica da pastagem, no qual o macrotiloma teve participa??o em 6,4% da ?rea experimental, com uma m?dia total de aproximadamente 380 plantas.