Fungicidal activity and biological characteristics of benzothiostrobin, a novel QoI fungicide

Fungicidal activity and biological characteristics of a novel QoI fungicide benzothiostrobin (Experiment code Y5247) were presented. The EC50 values of the benzothiostrobin inhibiting the mycelial growth of plant pathogen Rhizoctonia solani, Magnaporthe grisea, Sclerotinia sclerotiorum and Botrytis cinerea, on the AEA medium containing 50 μg/mL salicylhydroxamic acid (SHAM), were 0.004, 0.009, 0.016 and 0.023 μg/mL, respectively. The EC50 values of benzothiostrobin inhibiting spore germination of Colletotrichum capsici and Botrytis cinerea were 0.448 and 0.019 μg/mL, respectively. The protective and curative activities against powdery mildew caused by Blumeria graminis were 0.991 and 1.823 μg/mL, respectively. Benzothiostrobin showed no systemic translocation but penetrative activity on the wheat leaf. Benzothiostrobin appeared good bio-properties of rain-washing tolerance, adhesion and long persistence against Blumeria graminis on wheat leaf. Efficacy of the chemical against wheat powdery mildew still reached 72.48% when the pathogen was inoculated 14 days after the wheat seedling was sprayed with 25 μg/mL benzothiostrobin.