Crop rotation and genetic resistance reduce risk of damage from Fusarium wilt in lettuce

Fusarium wilt of lettuce, caused by the soilborne fungus Fusarium oxysporum f. sp. lactucae, a ects all major lettuce production areas in California and Ari-zona. In trials at UC Davis, we found that lettuce cultivars di er signi cantly in susceptibility to the disease, with some leaf and romaine types highly resistant under all test conditions. For more susceptible cultivars, disease severity is strongly in uenced by inoculum levels and ambient temperature. Management of Fusarium wilt requires an integrated approach that includes crop rotation to reduce soil inoculum levels and the us