Research Results

This is the first investigation into the infection by pycnidio- and asco-spores, as well as a mixture via wounds under the influence of cultivar resistance and fungicide seed treatment for blackleg disease in canola. The findings from this study suggested that it is feasible to produce ascospores and pycnidiospores in the lab and use these types of spores to test canola materials for blackleg resistance in both controlled environment and field conditions.

Clubroot poses a significant threat to canola growers. Although genetic resistance is critical for managing the disease, changes in pathogen virulence endanger its effectiveness. Second-generation resistance offers promise against pathotypes that can overcome first-generation resistance. However, without an understanding of pathogen virulence on second-generation resistance, we risk compromising its efficacy. This project provided data on the performance of second-generation clubroot-resistant cultivars in the field, along with insights into the virulence characteristics of pathogen populations collected from these cultivars.

Healthy soils form the basis of productive farming systems, and soil health tests can be useful tools to support good management decisions. The concept of soil health recognizes soil as a living and dynamic natural system, a notion that aptly fits in the realm of biology; however, soil health tests are often dominated by indicators of soil fertility and chemistry. Biological indicators of soil health remain understudied and underrepresented in soil health assessments.

This research has been an integrated and collaborative approach to addressing the major research priorities around the new disease, verticillium stripe, in Canada. It includes four specific objectives; to measure yield loss, monitor disease development, evaluate canola genotypes resistant to verticillium stripe and determine the interacting effects of verticillium stripe and blackleg.

We did not find that high rates of phosphorus (P) fertilizer affected crop yield and had only a minimal impact on the overall canola microbiome community structure. In our study, the intermediate-rate P supplied in a narrow opener was the most cost-effective fertilization method which generated equivalent canola yield to the high P rate. Our rhizobox studies showed that early canola growth was higher in plants where half of the root system was exposed to fertilized soil and the other half to unfertilized soil. Each half of the root system had a distinct root microbiome indicating that the root-microbiome system may confer the best advantage in soil where P availability is heterogenous as would be found in most field soils.

An understanding of the effectiveness of liming to control different pathotypes will help in decision making, since liming to increase soil pH can be costly and will not produce satisfactory results if the pathogen strains present are less sensitive to pH.

This research project will provide canola producers with practical approaches to managing small patches of clubroot. This will be especially important in situations where the patch represents a new introduction to the area or farm, or where commercial sources of resistance are not available.

The objective of this project is to determine the best combination of fertilizer source, placement, and timing to maximize yield, improve fertilizer N use efficiency and reduce losses of N2O and ammonia (NH3) on light textured soil (sandy loam) in south-central Manitoba.

Flea beetles (both Crucifer and Striped), diamondback moths and aster leafhoppers are major pests of canola, all feeding on the plant at different times throughout the growing season. The outbreaks of each of these insects are difficult to predict year to year and currently there are no resistant varieties available, leaving insecticide application as the only control option.

This project has identified several soil-derived bacteria that are effective at inhibiting disease progression caused by Sclerotinia sclerotiorum, a fungal pathogen of canola and other plants that causes stem rot, yield decline, and plant death. The mechanisms of action of the most effective biocontrol agent were investigated, and the bacterium was grown in formulations according to commercial standards. These industry-ready formulations were demonstrated to be as effective as the laboratory cultures, resulting in a biocontrol product that will soon be available as an option for producers.

Pollen beetles were susceptible to three of four insecticides tested. Yield reductions was detected at 7-9 beetles per plant but not at four beetles per ten sweep. Pollen beetles were not detected in the Prairies provinces and no native parasitoids were found attacking pollen beetle larvae in Atlantic Canada.