Take-all root rot, or Bermudagrass decline, is a root rot disease triggered by high rainfall or stress and manifesting as irregular yellow or light green patches two to three weekds after the pathogen has been active in the roots. This 3-page fact sheet was written by M. L. Elliott and P. F. Harmon and published by the UF Department of Plant Pathology, February 2011.
http://edis.ifas.ufl.edu/lh079