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对栽培在海南岛儋州地区的成龄巴西橡胶树（ＨｅｖｅａｂｒａｓｉｌｉｅｎｓｉｓＭｕｌｌ．Ａｒｇ．）苗端分生组织和维管形成层的季节活动进行光学和电于显微镜研究，结果表明，橡胶树在冬季叶黄时原来不活动的顶芽顶端分生组织即开始细胞分裂，这可以看作芽萌发的开始，如果不遇阻碍生长的低温（旬平均温度＜１８℃），９ｄ左右即发生肉眼可见的萌发，如遇阻碍生长的低温则肉眼可见的萌发延迟出现。春季新梢叶蓬淡绿末期顶芽顶端分生组织停止细胞分裂进入休眠；这种休眠芽可以在当年经几次活动和休眠形成新的叶蓬，也可以一直到下一个冬春季节才重新萌发。笔者认为顶芽的活动被成熟叶片控制，冬季叶片衰老脱落导致芽的休眠被解除，但由于有阻碍生长的低温而使芽被迫休眠。在冬季无叶期小枝次生韧皮都和维管形成层的超微结构与着叶期比较并无明显变化；这与温带树木不同，后者在准备休眠过程中，细胞结构发生导致获得抗寒性的若干明显改变。
The results of optical and electron microscopy studies on the seasonal activities of shoot apical meristem and vascular cambium of Hevea brasiliensis Mull. Arg. Cultivated in Danzhou, Hainan Island showed that when the rubber tree was in the original The top apical meristem of inactive bud begins cell division, which can be regarded as the beginning of bud germination. If it does not meet the low temperature (average temperature of ten days <18 ℃), the macroscopic germination occurs in about 9 days, Growing hypothermia is visible to the naked eye delay germination. Spring shoots Ye Peng light green end of the top bud end of apical meristem to stop cell division into hibernation; this dormant bud in the year by several activities and dormancy to form a new leaf Peng, you can not until the next spring and winter to re- Germination. I believe that the activities of the top buds are controlled by the mature leaves, leaves fall off in winter leading to bud dormancy was lifted, but because of the hinder the growth of low temperature buds were forced to sleep. There was no significant change in the ultrastructure of leaf-forming secondary lamina compared with the leaf-forming stage in leafless stage branchlets in winter; unlike temperate trees, the latter occurred during the preparation for dormancy, resulting in cellular structure gaining resistance Some significant changes in cold.