Detection of a Point Mutation (G143A) in Cyt b of Corynespora cassiicola That Confers Pyraclostrobin Resistance

Point mutation G143A in the cytochrome b (Cyt b) protein commonly confers resistance to quinone outside inhibitor (QoI) fungicides phytopathogenic fungi, including Corynespora cassiicola, which causes cucumber target spot disease. However, effect of on binding between QoI fungicide and Cyt protein, use LAMP (loop-mediated isothermal amplification) detect this point had not been reported previously C. cassiicola. In study, sensitivity 131 cassiicola isolates—collected from Shandong province, China 2019 2020—to pyraclostrobin was determined. The EC50 values ranged 1.67 8.82 μg/mL, sequencing results showed that all isolates contained mutation. Molecular docking suggested significantly alters affinity protein. Following development three primer pairs, best reaction condition for analysis 65 °C 60 min, detection limit 0.01 ng/μL DNA containing conclusion, conferring is widespread method can be used monitor caused by field.