Effective management of Fusarium wilt diseases in various crops is often accomplished through the development of disease-resistant cultivars. Efforts to develop disease resistance in lettuce cultivars have been ongoing for a number of years. Evaluation of lettuce types and cultivars has revealed a range of responses. A number of trials have shown that romaine types are more tolerant to infection and many of these cultivars do not show disease symptoms strongly. In contrast, few crisphead or leaf types demonstrate any level of resistance at all. However, in a 2016 variety trial conducted in a heavily infested field, two crisphead cultivars showed high levels of resistance, comparable to that of romaine type lettuces. This is a very encouraging effort.

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