Agronomic indicators of soybean (Cv. Celeste) potential as a summer green manure

• Autor(a) principal: Padovan, Milton Parron
• Data de Publicação: 2005
• Outros Autores: Almeida, Dejair Lopes, Guerra, José Guilherme Marinho, Alves, Bruno José Rodrigues, Ribeiro, Raul de Lucena Duarte, Oliveira, Fábio Luiz, Santos, Leandro Azevedo, Souto, Sebastião Manhães
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Gaúcha (Online)
• Texto Completo: http://revistapag.agricultura.rs.gov.br/ojs/index.php/revistapag/article/view/281
• topic: Glycine max, nodulation, biological fi xation nitrogen, organic agriculture.; Glycine max, nodulação, fi xação biológica de nitrogênio, agricultura orgânica.

Field plots conducted in Seropédica, State of Rio de Janeiro, have shown the potential of certain soybean cultivars,specially ‘Celeste’, for inclusion as a summer green manure in crops rotation systems. A randomized block design was used totest eight treatments (sampling dates) with fi ve replicates. Several variables evaluated at bimonthly intervals, corresponding to 25,40, 55, 70, 85, 100, 115 and 130 days after emergence of soybean seedlings (DAE) were: root nodulation, above-ground biomassaccumulation and nutrient contents (N, P, K, Ca and Mg) plant tissues, besides the contribution coming from nitrogen biologicalfi xation (NBF). A signifi cant biomass production by soybean was detected, with the highest dayly accumulation occurring between70 and 85 DAE (phases R2/R3). The maximum values, however, corresponded to 100 DAE and kept stabilized until 130 DAE (R6).At 70 DAE, ‘Celeste’ the soybean already presented a biomass volume adequate for cutting. The NBF ratio being intensifi ed atfl owering (R1/R2), attaining maximum levels by the time of legume (pod) and grain (R4/R5), coinciding with the greatest accumu-lation of above-ground biomass for incorporation to the soil.