Pesticide composition for controlling melon downy mildew

The invention discloses a pesticide composition for controlling melon downy mildew, and belongs to the technical field of pesticide compositions. The active ingredients of the pesticide composition ofthe present invention are propamocarb hydrochloride with a trademark of Keshuang belonging to Zhejiang Heben Science and Technology Ltd. and a Polygonum hydropiper extract, and account for 55% to 70%of the pesticide composition, wherein the weight ratio of the propamocarb hydrochloride to the Polygonum hydropiper extract is 1:40 to 20:1. The pesticide composition of the invention has better effect on seriously diseased fields after applied for 20 days, and has better effect on slightly diseased fields after applied for 10 days. The pesticide composition has better effect on melon downy mildew when the ratio of the propamocarb hydrochloride to the Polygonum hydropiper extract is 1:10 to 10:1. For the seriously diseased fields, the control effect is 91.85%-96.10%, and for the slightly diseased field, the control ef