Heading date (HD) is one of the most important traits for the
adaptation of rice to different cultivation areas and cropping
seasons, which can be divided into basic vegetative phase (BVP)
and photoperiod-sensitivity phase (PSP). It is essentially
determined by three factors, i.e. duration of the basic vegetative
growth (BVG), photoperiod-sensitivity (PS) and temperaturesensitivity
(TS). Several major genes forHDhave been identified
in rice: Ef-1, as a major gene controlling the duration of BVG, is
located on chromosome 10, and can accelerate floral initiation
under both short and long days, and also partially counteract the
effects of PS gene under long days