In Arabidopsis, a long day flowering plant, CONSTANS (CO) acts as a transcriptional activator of flowering under long day (LD) condition. In rice, a short day flowering plant, Hd1, the ortholog of CO, plays dual functions in respond to day-length, activates flowering in short days and represses flowering in long days. | Overexpression of PvCO1 a bamboo CONSTANS-LIKE gene delays flowering by reducing expression of the FT gene in transgenic Arabidopsis