Abstract
Approximately 120 days passes from pollination until fertilization in Ginkgo biloba. After pollination in late April or early May, the pollen develops in the pollen chamber until fertilization. The generative cell in the pollen grain divides into two cells ; one differentiates into a spermatogenous cell, the other into a sterile one. The spermatogenous cell then divides into two sacs, separated by a membrane ; these sacs, in turn, differentiates into sperms that swim to the egg to affect fertilization in early September. With the enlargement of the endosperm, the nucellus, enveloping it at the bottom of the pollen chamber, cracks. The crack is formed concomitantly with the development of a protuberance which is produced on top of the endosperm. The growth of the keeps pace, allowing the sperm to swim to the egg.
