Medicament and method for preventing and controlling phytophthora cactorum of palms

The invention discloses a medicament for preventing and controlling phytophthora cactorum of palms, which comprises sandofan and nitrogen, phosphorus and potassium elements, wherein the using concentration of the sandofan is 1 to 5 percent; and the nitrogen, phosphorus and potassium elements are effective components of carbamide and monopotassium phosphate, and the using concentration of the carbamide and the monopotassium phosphate is 0.1 to 1 percent. A method comprises the following steps: a, preparing the medicament, namely preparing sandofan wettable powder with the purity of 64 percent into 1 to 2 percent solution, and adding the carbamide and the monopotassium phosphate to prepare 0.2 percent medicament solution for preventing and controlling the phytophthora cactorum of the palms;b, well dressing a proper amount of coconut residuum on bases of the plants with plastic films; and c, adding the medicament solution prepared in the step a into the coconut residuum with an injectorin a dosage of 50-100ml pe