During the last two decades the modern techniques of histochemistry, electron microscopy, plant physiology, biochemistry, cell and molecular biology, immunology, and genetics have been applied to investigate the intricacies of the processes involved in embryo formation, and considerable new information has been generated. A better understanding of these processes has enhanced our capacity to manipulate fertilization and embryo development. This has changed the face of the embryology of angiosperms from a descriptive science to an experimental and applied science. The revolutionary progress...