ABSTRACT
Only ovules with larger embryo sacs and solid embryo sac wall are suitable for mechanical isolation. Embryo sacs are isolated under a microscope using entomological pins or a micromanipulator.
Some processes associated with fertilization and postfertilization development were observed in partly isolated embryo sacs of snowdrop (Galanthus nivalis from family Amaryllidaceae). Movement speed of sperm nucleus in the central cell of the embryo sac is about 3 pm min-1. Formation and growth of the male nucleolus in the secondary nucleus during triple fusion take about 150 minutes to complete and fusion of mature nucleoli about 10-15 minutes at 25°C. This object also enabled investigation of early endosperm formation in species with a nuclear-type endosperm, as well as growth and first division of the zygote (Erdelska, 1983).
