Abstract: The reintroduction population of Cycas debaoensis in Huanglianshan nature reserve and its natural population in Fuping village of Guangxi were studied. Reproductive features, including number of flowering plant, male/female ratio, pollination, seed setting, seedling survival, were investigated. The results showed that: (1) In reintroduction and natural population, the number of flowering plants were 149 and 49, the male/female ratio were 3.96:1 and 4.44:1, the flowering plants account for 31.63% and 19.52%, and the natural seed setting rate were 60.53% and 86.53% respectively. (2) For unshed seeds, the seed germination rate were 53.13% and 42.51%, first-year seedling survival rate were 0 and 3.56%, respectively, while for the seeds spread by gravity and the external force (rainwater, wind and animal), the seed germination rate were 42.51% and 38.46% respectively, first-year seedling survival rate were 74.46% and 88.26% respectively. (3) As with Fuping natural population, the effective pollinator of C. debaoensis in Huanglianshan reintroduction population was Erotylidae beetles. In average, the amount of beetles in the reintroduction population was 23.5 per female cones while in the Fuping natural population was 32.1, the reintroduction population had less beetles than that in Fuping natural population. The following conclusions were drawn from the research: the seed setting rate of reintroduction population was lower than the natural population, which was probably due to the relatively small number of pollinators at reintroduction site. The seed dispersion by rodent and other external forces could significantly improve seedling survival rate and directly affect the planting and distribution of seedlings, and had important influence on replenishment and renewal of the population. On the whole, the reintroduction population of C. debaoensis in Huanglianshan had successfully completed the growth and reproduction process, and had the ability of self-renewal.

Key words: cycad, reintroduction, reproductive features, pollination

摘要： 以位于广西黄连山自然保护区的德保苏铁Cycas debaoensis回归种群为对象，从开花情况、传粉媒介、传粉昆虫数量、结实率、种子散播媒介和方式等方面，与德保苏铁模式产地的自然种群进行比较研究。结果表明，2016年回归种群与自然种群开花植株分别为149和49株，雄雌性比分别为3.96∶1和4.44∶1，开花植株占比分别为31.63%和19.52%，自然结实率分别为60.53%和86.53%。留存在雌株上的未脱落种子一年内的萌发率分别为53.13%和42.51%，一年内幼苗存活率分别为0和3.56%；因重力或外力(雨水、风和动物)搬运后散布的种子一年内的萌发率分别为42.51%和38.46%，一年内幼苗存活率分别为74.46%和88.26%。与自然种群一样，回归种群的有效传粉者为大蕈甲科甲虫，但传粉昆虫数量较少，每雌球花有23.5头甲虫。回归种群结实率低于自然种群，可能的原因是传粉昆虫数量相对较少。啮齿动物等外力对种子的散布能显著提高幼苗存活率并直接影响幼苗的定植与分布，对回归种群的补充与更新有重要影响。总体上，黄连山德保苏铁回归种群在自然界中已能顺利完成生长和繁殖进程，基本具备自我更新能力。

关键词: 苏铁, 回归, 繁殖特征, 传粉者