The Biological Activity of JS-B against Phytophthora capsici
WANG Chun-mei1, GUAN Wei1,2, LIU Zhi-heng2, FANG Shu1,2, CHEN Hao1, CAI Chun3, SHI Zhi-qi1(1.Institute of Food Safety, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; 2.Collage of Plant Protection, Shenyang Agriculture University, Shenyang 100161, China; 3.Nanjing University of Science and Technology, Nanjing 210094, China)
Antifungal activity of JS-B, a kind of modified osthol derivative, was investigated. The EC50 values of JS-B inhibiting mycelial dry weight and zoospore germination of Phytophthora capsici were 43.74 and 86.03 mg/L, respectively. JS-B showed some protective and curative efficacy in controlling pepper blight to some extent under pot experiment. JS-B could be absorbed by the roots of pepper. The control efficacy value of JS-B applied at the concentration of 1 000 mg/L through soil drench, was 67.16%. The control efficacy of JS-B against pepper blight, when applied 1, 3 and 8 d at the concentration of 400 mg/L before inoculation with zoospore suspension of P. capsici, were 71.95, 61.90 and 66.72%, respectively. The effect of JS-B was correspond with dimethomorph. It indicated that JS-B had some persistence activity against pepper blight.