01827naa a2200241 a 450000100080000000500110000800800410001910000250006024500910008526000090017650001440018552010250032965000110135465000130136565000090137865300220138765300250140965300120143470000170144670000180146370000160148177300880149710993182019-06-19       1999    bl uuuu     u00u1 u    #d1 aAZEVEDO, D. M. P. de  aThe effect of cover crop and crop rotation on soil water storage and on sorghum yield.  c1999  aTítulo em português: Efeito de cultura de cobertura e de rotação de cultura no armazenamento de água do solo e no rendimento de sorgo.  aCrop rotation and cover crop can be important means for enhancing crop yield in rainfed areas such as the lower Coastal Bend Region of Texas, USA. A trial was conducted in 1995 as part of a long-term cropping experiment (7 years) to investigate the effect of oat (Avena sativa L.) cover and rotation on soil water storage and yield of sorghum (Sorghum bicolor L.). The trial design was a RCB in a split-plot arrangement with four replicates. Rotation sequences were the main plots and oat cover crop the subplots. Cover crop reduced sorghum grain yield. This effect was attibuted to a reduced concentration of availabre soil N and less soil water storage under this treatment. By delaying cover termination, the residue with a high C/N acted as an N sink through competition and/or immobilization instead of an N source to sorghum plants. Crop rotation had a significantly positive effect on sorghum yield and this effect was attributed to a significantly larger amount of N concentration under these rotation sequences.  acotton  aAlgodão  aSoja  aRotation sequence  aSequencia de rotacao  aSoybean1 aLANDIVAR, J.1 aVIEIRA, R. M.1 aMOSELEY, D.  tPesquisa Agropecuária Brasileira, Brasília, DFgv. 34, n. 3, p. 391-98, mar. 1999