Fecha de publicación: -- Fuente: WIPO "tomato" To provide a method for plant treatment, which is capable of further promoting growth of a plant by using a compound such as ergothioneine. A plant treatment method of the present invention includes treating a propagule of a plant with an active component which is a compound represented by Formula (I) below or a tautomer thereof, or an agronomically acceptable salt thereof:where in Formula (I), R1 and R2 each independently represent a hydrogen atom or an alkyl group having from 1 to 4 carbons, and R3, R4, and R5 each independently represent an alkyl group having from 1 to 4 carbons.