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油松雄球花于６月下旬开始分化，小孢子发生在翌年的４月２０日左右，４月底或５月初散粉．成熟的花粉粒为４个细胞．雌球花７月中旬分化，次年４月下旬或５月上旬形成大孢子母细胞，经减数分裂后，形成大孢子．雌配子体经历游离核、细胞化、颈卵器及卵细胞形成等阶段后，５月下旬受精，从传粉到受精约需１３个月．胚胎发育包括原胚、胚胎选择及发育和胚胎成熟３个阶段，历时３个半月．不同无性系在雌雄球花发端时间和大小孢子发育进程上存在较大差异，观察的５个无性系进入同一发育阶段的时间最多可相差１０ｄ，平均变幅为一周上下．该文还对新梢生长与花芽分化、胚珠和花粉败育作了讨论．
Pinus tabulaeformis flowers began to differentiate in late June, microspores occurred in the following year on April 20 or so, the end of April or early May loose powder. Mature pollen grains are 4 cells. Female ball flower differentiation in mid-July, the following year in late April or early May to form megaspore mother cells, after meiosis, the formation of megaspores. After the female gametophyte undergoes stages of free nucleation, cellification, archegonial process and egg cell formation, it can fertilize from late pollination to fertilization in about 13 months. Embryonic development, including embryo, embryo selection and development and embryonic maturity in three stages, lasted 3 and a half months. Different clones in the male and female flowers spend time and development process of large and small spores there is a big difference between the observation of the five clones into the same development stage up to a difference of 10d, the average amplitude of up and down a week. The article also discussed the shoot growth and flower bud differentiation, ovule and pollen abortion.