OBSERVATION ON EMBRYO DEVELOPMENT OF MASSON PINE

Under natural condition, the development of a mature pollen took 6 months to complete. The first five days after ovuliferous scale open were of efficiency for pollination. The phase of free nuclei of female gametophyte lasted for 12 months, and it took about 7 days to develop from nuclei phase to cell phase. There were two or three archegoniums in Masson Pine. The fertilization took place in the 13th month after pollination. The development phase of proembryo was about 30 days, young embryo 40 days and mature embryo 60 days. The production of mature seeds needed 24 months to go since the differentiation of floral buds. According to the observation on morphological development, we found that there usually were unnormal pollens and pollen sterility in every developing stage because of low temperature and freezing.