Grant: Alliance Grants

Clubroot, caused by Plasmodiophora brassicae, is an important and damaging disease of brassica crops such as canola and cabbage. The goal of this collaborative project is to develop improved strategies for clubroot management and provide them to Canadian producers. Genetic resistance is currently the only strategy used for clubroot management, but resistance can quickly be overcome. Growers need to know which pathotypes are present in their region to be able to select cultivars that carry resistance specific to those pathotypes. Also, the project will contribute to the development of more efficient ways for pathotype identification through molecular assessment and sequencing. Finally, new approaches are needed to reduce or suppress pathogen inoculum in soil, which would help to make genetic resistance more durable.Root exudates can stimulate resting spore germination and subsequent root infection, but new research shows that their impact may be affected by the microbial community on / near roots. The effect of microbial community will be examined to determine if there is any association between spore germination and subsequent reduction in spore concentration with specific microbial communities. Soil characteristics such as pH or boron and calcium content/base saturation have reduced clubroot development in some studies. The interaction of calcium and boron and soil properties with microbial communities will be examined. The effectiveness of cover crops for clubroot reduction will also be assessed.Early detection is key to effective clubroot management. The distribution and spread of clubroot in Ontario will be monitored and the predominant pathotypes will be identified using a differential series (a set of host lines with genetic resistance). This important information will be provided to growers so that they can select a resistant cultivar for production in their fields.