Abstract: Under microscope, the nucellar filament of Phaius tankervilliae(Aiton) Bl. could be observed on 10^th day after pollination, archesporial cell on 20^thday, megasporocyte on 24^th day, the functional megaspore on 30th day; and 8-nucleate embryo sac on 41^th day. And then double fertilization finish and early globular embryo emerg. The researchs on isozymes indicated that some varieties of isozyme loci present during the embryo development. There are 7 esterase(Est) loci and 5 acid phosphatase (Acp) loci during the periods between nucellar filament and early globular embryo; both of Est and Acp appeared the most diversity in the stage of 8-nucleate embryo sac. Est-7 and Acp-4 always express in the whole developmental stages , and Est-4 and Acp-3 just express in the stage of 8-nucleat embryo sac of Phaius tankervilliae(Aiton) Bl., but Acp-2 express in all developmental stages except the 8-nucleat embryo stage. Est-1 only express in the stage of 8-nucleat embryo sac and metaphase I of meiosis. Further studies should be done to confirm if Est-4, Acp-2 and Acp-3 could regulate the development of 8-nucleat embryo sac.

Key words: Phaius tankervilliae(Aiton) Bl, Est, Acp, ovule, polyacrylamide gel electrophoresis