Powdery mildew is a highly recognizable disease with pronounced colonies of white on foliage and, for some species, on petals. Due to the high number of spored produced, powdery mildews often develop resistance quickly to fungicides. Starting in 2012, IR-4 initiated a series of regional projects to examine new fungicides and biofungicides for powdery mildew management. In addition, we performed a literature review. Contained in the project summary are outcomes from 96 experiments conducted in greenhouses and or outdoors. Specific powdery mildew pathogens included: Erysiphe azaleae, Erysiphe knautiae, Erysiphe lagerstroemia, Erysiphe lonicerae var. lonicerae, Erysiphe monardae, Erysiphe polygoni, Erysiphe pulchra, Golovinomyces cichoracearum, Golovinomyces orontii, Oidium spp., Podosphaera pannosa, and Podosphaera xanthii. Across species, the best performing products and actives included Aveylo, Bayleton, Broadform, Gatten, Heritage. Magus. Mural, NF-149 (cyflufenamid), SP2478, and XDE-659.
Link to Summary: Powdery Mildew Efficacy Data