Sclerotinia stem rot, also known as white mold, is a disease caused by the Sclerotinia sclerotiorumis fungus, which is found throughout the world. In Québec this fungus often infects soybean fields. Yield losses can run from 0% to 20% depending on factors such as moisture, temperature, and cultivar. Even higher losses can result when conditions are more favourable to disease development. To date, we have no method for predicting the risk of sclerotinia stem rot in Québec crops, i.e., a tool that allows for the rational application of fungicides based on necessity and cost-effectiveness. Predictive models are used in the United States for soybean sclerotinia stem rot and in Saskatchewan for canola sclerotinia stem rot but these tools have yet to be validated in Québec. This project aims to test at least one predictive model, i.e., the Michigan State University model, and modify it or develop a version better suited to Québec conditions. Over a three-year period, we will expose fields to Sclerotinia sclerotiorumis in order to try and better understand how environmental factors (temperature, precipitation, moisture, wind, and soil type) and agronomic factors (row spacing, row covering/closing, cultivar, flowering date, tillage, weed quantity, and rotations in the last five years) affect spore germination, i.e., the appearance of apothecia and the occurrence of sclerotinia stem rot in the field. Three years of meteorological data, as well as other data and observations pertinent to infection rates will be used to develop and validate a predictive model. During the course of the project we will incorporate one or more models into the CIPRA software. The most satisfactory model will be adopted and retained at project end. A better understanding of risk factors that favour the development of this disease will help Québec farmers adopt more environmentally friendly and cost-effective control strategies.
From 2019 to 2021
Pest, weed, and disease control
This project will result in the development of a cost-effective and environmentally friendly strategy for controlling soybean sclerotina stem rot.
Centre de recherche sur les grains
This project’s main goal is to demonstrate how to satisfy most of the requirements of a strongly N-dependent crop by improving N-supply synchronization, while protecting the farmers’ prior year revenue-generating window.
Researcher: Christine Landry
A literature review, a survey of organic grain producers, and an analysis of historical yield and climate data in order to document the effects of climate extremes on yields and soil nutrient availability.
Researcher: Marc-Olivier Gasser
Testing the efficacy of four biofungicides against Sclerotinia in soybeans.
Researcher: Luc Belzile