Understanding the basis of agrochemical resistance in biotrophic grapevine pathogens

The development of resistance to agrochemicals is an ever-increasing problem in agriculture. Previous work has shown widespread prevalence of known resistance alleles in the main biotrophic grapevine pathogens Erysiphe necator (powdery mildew) and Plasmopara viticola (downy mildew) to many commonly used agrochemicals. This project aims to use genome sequencing technology to determine the genetic basis for resistance in downy mildew to metalaxyl. This information will provide the means to design a simple genetic test for the presence of field resistance. The new knowledge generated, and tools developed, will improve grapegrowers’ ability to manage one of the most economically important diseases in Australian viticulture, powdery mildew.