This study explores a ddPCR-based protocol to measure quantitative resistance (QR) to blackleg in canola. Once developed and validated, the method will be used to quantify QR in canola cultivars and help screen QR traits in commercial canola breeding lines.
More than 50 canola hybrids/inbred lines with varied blackleg resistance in multi-year field trials were gathered from seed companies. Initial experiments identified a relationship between the level of QR and the amount of pathogen DNA detected in infected canola tissues. This relationship is being validated using petiole and cotyledon inoculations under greenhouse and field conditions. The results showed a high correlation between disease levels observed in both conditions and QR based on ddPCR measurement. The next step is to test more commercial breeding lines/cultivars for QR screening/identification/quantification.