Early flowering in Arabidopsis induced by DNA base analogs

Various isogenic lines of Arabidopsis differing in a single factor controlling flower initiation were cultured aseptically on media containing bromodeoxycytidine and bromodeoxyuridine (10(-5) M). The wild type under short-day illumination (8 hours daily) and the late mutant gi (2), in both continuous light and under short day, responded with dramatically earlier flower initiation. Another late mutant (ld) failed to respond. The effect of the DNA base analogs was nullified by the corresponding normal deoxyribonucleosides but not by the corresponding normal ribonucleosides.