Sour Rot Management

Written by

Phil Brannen

June 30, 2017

After the meeting on Wednesday, there was a request for more information on sour rot management through use of insecticides for control of SWD. I contacted Megan Hall, who conducted this research at Cornell. She indicated that the 2016 research continued to support the use of MustangMaxx. She states, “If a grower knows that they regularly see sour rot in a particular variety, I recommend beginning to spray at approximately 15 Brix using OxiDate and MustangMaxx weekly until harvest.” She still recommends the Oxidate, but she also indicated that the MustangMaxx is the heavy hitter. Without MustangMaxx, the Oxidate product does nothing, according to Megan. Please realize that you will need to incorporate other SWD-active insecticides in a rotation with MustangMaxx, as you do not want to go to that well too often — resistance will develop. We hope to repeat and add to this research at some point in the future, but for now, this is the best information I have personally found to suggest that we can manage sour rot in any way. See below for a poster that gives further details of this research and the results.

Sour Rot Poster

Posted in: Bunch Grapes, Pest management Guidelines

Phil Brannen

Phil Brannen is a Professor in the Plant Pathology Department at the University of Georgia. He attended the University of Georgia for his undergraduate degree in Plant Protection and Pest Management, where he also received an M.S. in Plant Pathology, followed by a Ph.D. in Plant Pathology from Auburn University. He has extensive experience with disease management programs in numerous cropping systems. He serves as the extension fruit pathologist for Georgia – conducting research and technology transfer for multiple fruit commodities. His efforts are directed towards developing IPM practices to solve disease issues and technology transfer of disease-management methods to commercial fruit producers. He also teaches the graduate level Field Pathology Course, the History of Plant Diseases and their Impact on Human Societies Course, team-teaches the IPM Course, coordinates the Viticulture and Enology in the Mediterranean Region Course (Cortona, Italy), and guest lectures in numerous other courses throughout the year.