The present invention discloses a method of inhibiting an ethylene response in a plant, comprising step of applying to at least one portion of the plant an effective ethylene response-inhibiting amount of a H1-cyclopropene-1-propanoic acid salt (CPAS). A method of prolonging the life of a cut flower, comprising applying to the cut flower an effective life-prolonging amount of CPAS and a method for the production a CPAS, comprising steps of (i) preparing 4-bromo-4-pentenoic acid or derivatives thereof； (ii) producing 1-cyclopropene-1-propanoic acid； and (iii), converting this acid into its water soluble salt, especially its sodium salt are presented. Additionally, a new family of water soluble CPAS inhibitors for ethylene response in a plant is disclosed.
