Abstract
The aged rice plants produced their flower bud primordia by fewer short-day treatments and under longer day-length as compared to the young plants. On the other hand, the floral initiation of the plants showing high intensity in the vigour of vegetative growth was delayed than that of the plants showing low intensity, although both the plants were sown on the same date. From these facts, it is inferred that aging effect on floral induction is due to the decrease in the vigour of vegetative growth during the course of development.
