Integrated Management of Strawberry Diseases

Organic Fungicides and Biocontrol products
for Strawberry Disease Control

 Most organic fungicides and biocontrol agents are not highly effective against the overall disease complex on strawberry. A number of products including sulfur, salts and oils will provide good control of powdery mildew if applied on a 7 to 10 day schedule; however, these materials have little or no activity against most of the other leaf spot or fruit rot diseases. Emphasis for controlling these diseases, as well as powdery mildew, should be placed on the selection and use of disease resistant cultivars (Table 1). If a high level of resistance is not available in adapted varieties, growers should at least avoid the selection of highly susceptible varieties. Copper fungicides have limited use on strawberry. The potential for plant injury using copper fungicides is high on strawberry. In addition, copper fungicides are not highly effective against most of the leaf spot and fruit rot diseases. In order to apply sufficient copper to obtain control, the potential for plant injury is probably unacceptable. Copper fungicides have been recommended and used for control of angular leaf spot (bacterial blight) with varying levels of success. Once the disease is established in the planting, copper fungicides will do little to control it. There are several biocontrol products registered for control of Botrytis fruit rot. Their efficacy under moderate to severe disease pressure needs to be determined.