Abstract:In order to investigate the reproductive features of Cymbidium faberi and clarify reason for the low seed germination, the reproductive features mainly on the aspects of ovule development and developmental events distribution were investigated. Results indicated that the embryo sac development of C. faberi followed a rarely bisporic pattern and the development of ovules showed hugely asynchronized. Megasporogenesis mainly occurred during 40 to 45 days after pollination (DAP). Approximately 40 DAP, about 22.33% archesporial cells differentiated into megasporocytes. After the first meiotic division, the megasporocyte polarized into two equal dyad cells. The chalazal one continued to enlarge via vacuolation and then was formed into the functional megaspore. During 45 to 55 DAP, megasporogenesis finished while embryo sac began to development. The megaspore first developed into uni-nucleate embryo sac directly. After the second meiosis, the two-nucleate embryo sac was formed showing two nuclei migrating to the opposite end of the sac. As a result of the mitosis of both formed nuclei, the four-nucleate embryo sac was formed and, the additional divisions resulted in an eight-nucleate embryo sac. Uni-(27.33%), two-(30.67%) and four-nucleate embryo sac (9.33%) were all observed at 45 DAP. About 32.33% of ovules, the highest probability, had developed into mature embryo sacs at 55 DAP. At 60 DAP, most of the ovules had finished megagametogenesis. The asynchronous development of ovules is probably responsible for the different embryo development in C. faberi which might results in the low ratio of seed germination in vitro . The study may provide important guidance for further researches on embryo development and determining the time for harvesting seed.