You didn’t make any fungicide applications to deal with pink rot. However, in late July or early August you find some pink rot in the field. Is it too late? Can you still apply fungicides and get some level of disease control?
This article summarizes the best management practices for pink rot of potato and discusses a research project sponsored by the Idaho Potato Commission. The purpose of the research was to compare pink rot control when fungicides were applied according to label directions (prior to infection) to fungicides being applied after pink rot has already developed in the field.
The take home message… If you don’t treat preventatively, you are better off not treating at all. Late season applications were similar to not applying at all when they were made after pink rot was already found in the field.
See the attached report below for the entire report.