Effectively managing powdery mildew with fungicides is best achieved by initial application ideally before but no later than the first visible presence of the disease. Subsequent applications of fungicides throughout the life of the crop are necessary. The fungus responsible for powdery mildew on melons has developed resistance to some fungicides in the past, so maintaining long-term effectiveness of fungicides currently available requires the use of resistance management strategies. One effective approach is to alternate among products with different modes of action. Treatment programs containing different fungicides and application sequences were evaluated for the last two years at the UA Yuma Agricultural Center. Both trials yielded very similar results, which can be examined in this report.

To contact Mike Matheron go to: matheron@ag.arizona.edu.

For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
College of Agriculture, The University of Arizona, Tucson, AZ.