Ruzigrass root persistence and soybean root growth

Aims Cropping systems using forage grasses as cover crops have been effective in soil conservation and nutrient cycling, but root persistence of ruzigrass (Urochloa ruziziensis) is significant, and may impair root growth of the next crop. However, it is unknown how this would interfere with soybean...

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Detalles Bibliográficos
Autores: Rosolem, Ciro A. [UNESP], Oliveira Neto, Leontino [UNESP], Costa, Vladimir E. [UNESP], Grassmann, Camila da Silva [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/196173
Acceso en línea:http://dx.doi.org/10.1007/s11104-019-04198-4
http://hdl.handle.net/11449/196173
Access Level:acceso abierto
Palabra clave:Cropping system
Soybean
Ruzigrass
Roots
Crop rotation
Descripción
Sumario:Aims Cropping systems using forage grasses as cover crops have been effective in soil conservation and nutrient cycling, but root persistence of ruzigrass (Urochloa ruziziensis) is significant, and may impair root growth of the next crop. However, it is unknown how this would interfere with soybean root growth and yield under field conditions. Methods Ruzigrass root persistence during soybean development, and its effects on soybean yield were studied under field conditions. Ruzigrass and soybean were grown alone or in rotation, and roots were sampled every 30 days and evaluated using carbon isotope discrimination. Results Despite temporary impairment of soybean root growth in the uppermost soil layer, there was no effect of ruzigrass on soybean yield. The ruzigrass root decay rate was high in the first 30 days after desiccation, and then it slowed down. Soybean roots grew slowly up to 30 days after planting (DAP, V7) and then peaked at 90 DAP (R5). Conclusions Soybean root growth and yield are not affected by decaying ruzigrass roots. Around 50% of the ruzigrass roots are mineralized before soybean flowering. However, by soybean harvest there are still from 25 to 28% of non-decomposed ruzigrass roots up to the soil depth of 0.20 m.