[Advances in the study of fertilization mechanism of angiosperms]

The fertilization of angiosperms is a complicated and ingenious process. When pollen tube arrives at ovary and enters embryo sac by degenerated synergid, two sperm cells are released into the cell. Two sperm cells are connected together at first in the pollen tube, and then separated in the degenerated synergid. One of the two sperm cells moves to the egg cell and fuses with it to form a zygote, and another one to central cell and fuses to form the endosperm, which completes the double fertilization. The process of male and female gamete recognition is a key link but we know nothing about it. This review introduced the study of cell cycle of male and female gametes before fertilization; discussed the question of synergid degeneration; analysed status of research into the movement of both sperm cells in degenerated synergid; and evaluated the preferential fertilization of sperm cells and the egg cell activation of angiosperms. The results of recent research into these questions may help us to understand the fertilization mechanism in angiosperms.