Fusarium Wilt of Lettuce

California is the largest producer of lettuce in the United States. One of the challenges faced by lettuce growers is the effective management of soilborne diseases. Among those diseases is Fusarium wilt, caused by the fungal pathogen Fusarium oxysporum forma specialis lactucae. This is a relatively new disease in California and has only recently been discovered in the state's major production areas near the coast. Our project was initiated in 2002, in order to provide the basic information needed to achieve more effective management of the disease. This includes development of reliable and efficient methods for detection of the pathogen in soil and testing currently grown lettuce varieties to determine their relative susceptibility to the disease.