Abstract: The pollen of P.yunnanensis is shed at the four celled stage in March. The pollen germinated at the top of nucellar tissue, then the pollen tube grew into thc nucellar tissue and the tube nucleus into the pollen tube. In the second year, the resting pollen tube revives its activity in the nucellus towards the March. The two unequal male gamete formed in the April. Surro-unding the male nuclei some starch grains were observed. The pollen incubated in the medium containing sucrose grew much slower than that in BKBM-WS.The pollen tube and pollen grains contained abundent starch grains.

Key words: Pinus yunanensis

摘要： 云南松（Pinus yunnanensis Fr·）花粉于三月在四细胞时期散粉。花粉在珠心顶端萌发，然后花粉管进人珠心组织，管核进入花粉管。第二年三月，休眠的花粉管在珠心内恢复活动，四月形成二个不等的雄配子。在雄配子周围有一些淀粉粒分布。花粉孵育在含蔗糖的培养基中生长要比在BKBM－WS培养基中缓慢。花粉粒及花粉管中含有大量直径4一8微米的淀粉粒，在不含蔗糖的培养基中，淀粉粒积累较少，直径约2一5微米。培养在2一5’C低温下的花粉可以缓慢地萌发，但不能形成雄配子。

关键词: 云南松, 雄配于, 人工培养