克隆整合对天胡荽分株间有性和克隆繁殖策略的影响

Effect of clonal integration on sexuality and clonal reproductive strategies of Hydrocotyle sibthorpioides

研究了克隆整合特性对天胡荽在异质性土壤养分环境中繁殖策略的影响。结果表明:克隆整合可显著提高相连分株中处于低资源条件下近端分株的结果数和坐果率、总种子数量,及其单个克隆分株的平均结籽数,但对各处理单果重量的无显著影响。克隆整合有利于促进资源缺乏端的有性繁殖;促进生理顶端分株的克隆繁殖。在低资源条件下,克隆整合促进近端分株的有性繁殖以及远端分株的克隆繁殖;相反则促进远端分株的有性繁殖和克隆繁殖。因此,克隆整合特性是天胡荽对异质性环境的重要适应对策,它使天胡荽能够扩展到不适合植物生长的低养分斑块中,从而增加了天胡荽对恶劣环境的繁殖适合度及适应能力。

The effects of clonal integration characteristics on the reproductive strategies of Hydrocotyle sibthorpioides in heterogeneous soil nutrient environment were studied in this paper.The results showed that clonal integration could significantly increase the number of fruits,fruit set,total seed number of proximal ramets and the average seed number of individual clonal ramets under low resource conditions,but had no significant effect on the single fruit weight of each treatment.Clonal integration is conducive to promoting sexual reproduction at the resource-deficient end and clonal reproduction of physiological apical ramets.Under low resource conditions,clonal integration promotes sexual reproduction of proximal ramets and clonal reproduction of distal ramets;on the contrary,it promotes sexual reproduction and clonal reproduction of distal ramets.Therefore,clonal integration is an important adaptation strategy for H.sibthorpioides to heterogeneous environments.It enables H.sibthorpioides to expand into low nutrient patches unsuitable for plant growth,thus increasing its reproductive fitness and adaptability to harsh environments.