Start Date: Jul 01, 2010
End Date: Sep 30, 2013
We will conduct a series of field studies on canola to reach our objectives. Our studies will define the environmental, microclimatic, and biological conditions that are needed to create the levels of disease infection that can be obtained with sclerotia and ascospores. Sclerotia are readily obtained from seed processing facilities that process confection sunflower seed. Ascospores are produced in vitro and collected for field use. By comparing the infection levels of these two infection mediums in the field under five defined misting and several soil water regimes we will determine which parameters are necessary to effectively establish a Sclerotinia stalk rot epidemic in canola. The environmental conditions will be recorded with a North Dakota Agricultural Weather Network station located at the Langdon Research Extension Center and microclimates will be carefully monitored with Onset leaf wetness sensors placed at three levels within the canopy, soil water measurements and disease assessments. Disease incidence will be quantified by collecting petals and plating on selective media for Sclerotinia sclerotiorum. The petals will be sampled from multiple levels within the canopy during the flowering growth period. The most effective concentration of ascospores for infection will be determined by applying several ascospore concentrations to the canola at different timings with and without supplemental water application that modify the microclimates over the growing season. In addition, the benefit of cultivars with different flowering windows will be compared at multiple planting dates in these environments with buried sclerotia and backpack applied ascospores.