Asparagus officinalis seedlings treated with either thiocarbamates or carbamates are induced to flower within 2-3 weeks of application. SDS-PAGE and 2-D PAGE resolutions of total soluble proteins of treated seedlings showed the accumulation of an acidic 17 kDa polypeptide. Partial amino acid sequence of the acidic protein showed homology to the wound-responsive A. officinalis PR 1, AoPR1. We named this protein EFP, early flowering protein, owing to its advanced appearance during the early transition from vegetative to floral phase. Carbamates and thiocarbamates that induced more than 80% flowering rates corresponded with increased level of EFP while compounds that are weak flower inducers showed reduced amount of EFP. The observation thus defined the correlationship of EFP to variable flowering rates.