FLOWER DEVELOPMENT OF DIPTEROCARPUS ALATUS

Abstract

Flower development of Dipterocarpus alatus Roxb. was investigated for 196 days from primordial inforescence to fruit maturity. It was studied by morphological and anatomical observation. The primordial inforescence and flower primordial appeared at the same time. The flowers were borned in a simple raceme. Each flowers consisted of five green sepals, five petals and three carpels surrounded by thirty stamens. The carpels developed into three locular ovary, style and stigma. Each locule comprised of two anatropous ovules which were protruded from the central column and formed an axile placentation arrangement. The development from flower primordial to anthesis took about seventy days. After fertilization, the zygote was differentiated into an embryo. At this stage, the petals, stamens and style were absissed. On the other hand, the sepals were persisted, particularly a pair of them elongated rapidly and turned to be wings. It took eighteen weeks for fruit to develop from small size to full size and mature.