Three growth phases

The growth of the rice plant is divided into three phases:
 

1. vegetative (germination to panicle initiation);

2. reproductive (panicle initiation to flowering); and

3. ripening (flowering to mature grain)

• In the tropics, the reproductive phase is about 35 days and the ripening phase is about 30 days.

• The differences in growth duration are determined by changes in the length of the vegetative phase.

• For example, IR64 which matures in 110 days has a 45-day vegetative phase, whereas IR8 which matures in 130 days has a 65-day vegetative phase.