The present invention provides a nucleic acid molecule encoding a CAULIFLOWER (CAL) gene product such as a nucleic acid molecule encoding Arabidopsis thaliana CAL and a nucleic acid molecule encoding Brassica oleracea CAL (BoCAL). The invention also provides a nucleic acid molecule encoding a truncated CAL gene product such as a nucleic acid molecule encoding Brassica oleracea var. botrytis CAL (BobCAL). The invention also provides a nucleic acid containing the Arabidopsis thaliana CAL gene, a nucleic acid molecule containing the Brassica oleracea CAL gene and a nucleic acid molecule containing the Brassica oleracea var. botrytis CAL gene. The invention further provides a kit for converting shoot meristem to floral meristem and a kit for promoting early flowering in an angiosperm. The invention provides a CAL polypeptide and an antibody that specifically binds CAL polypeptide. In addition, the invention provides the truncated BobCAL polypeptide and an antibody that specifically binds truncated BobCAL polypeptide. The invention further provides a method of identifying a Brassica having a modified CAL allele by detecting a polymorphism associated with a CAL locus, where the CAL locus comprises a modified CAL allele that does not encode an active CAL gene product.