Fuente: WIPO "tomato" An eco-friendly and safety-conscious disinfectant composition for plants contains (A) a straight-chain aliphatic alcohol with 8 or more and 12 or less carbons as a disinfectant component, (B) a polyoxyalkylene sorbitan fatty acid ester, and (C) one or more solvents. A mass ratio between the component (A) and the component (B), (B)/(A), is 0.05 or more and 0.9 or less. A disinfectant treatment liquid for plants contains the disinfectant composition and water.