History of rapid blight in the southwestern U.S.

The Arizona Cactus and Pines Golf Course Superintendent's Association sponsored a Rapid Blight Summit at Superstition Springs Golf Course in Mesa Arizona on January 24th, 2007. Speakers included Dr. Bruce Martin, Clemson University, Dr. Mary Olsen and Dr. David Kopec, University of Arizona, Dr. Frank Wong, University of California, and Dr. Larry Stowell, PACE Turfgrass Research Institute. Each speaker reviewed the history of their involvement in the project and practices that can be used to improve management of the disease. For a detailed history of the discovery and development of management practices for rapid blight, refer to the Feature Article published on-line by the American Phytopathological Society.

Stowell's presentation (395 KB) proposed a maximum soil guideline of 110 ppm Mehlich III extractable sodium to reduce rapid blight. The sodium guideline is based on laboratory research conducted by Martin and Olsen that revealed sodium, not necessarily total salts alone, resulted in serious rapid blight. A maximum soil salinity of 2.0 dS/m saturated paste extract proposed by Wong was also included in the guidelines.