从系统角度分析克隆生长对婆婆纳属植物适应性的影响  

Effects of Clonal Growth on Adaptability of Veronica Plants from a Phylogenetic Perspective

作　　者：王建成[1] 韩路[1] 潘伯荣[1] 

机构地区：[1]中国科学院新疆生态与地理研究所干旱区生物地理与生物资源重点实验室,新疆乌鲁木齐830011

出　　处：《干旱区研究》2016年第4期773-779,共7页Arid Zone Research

基　　金：新疆维吾尔自治区自然科学基金项目(2013211A050)

摘　　要：克隆植物由于克隆性的存在,在很多方面同非克隆植物存在差异。为了解克隆生长对植物适应性的影响,以婆婆纳属(Veronica)植物为对象,从系统角度开展了其属内克隆植物与非克隆植物的比较研究。结果显示:1克隆性并不是一个保守性状,婆婆纳属的祖先状态中克隆植物可能性为0.94;2克隆植物大多为多年生植物,花部具有更大的吸引力,而非克隆植物中一年生植物占优势;3与克隆植物相比,非克隆植物更加耐干旱和高温。在婆婆纳属的进化过程中,随着气候日益变得干旱,利用种子的耐旱特性逃避恶劣时期的策略受到青睐,克隆生长的相对重要性逐渐降低,以致于一些植物最终转换成了非克隆植物,其对干旱环境的适应性更高,也能耐受更高的温度,从而能够适应当地环境的变化。Because of clonality,clone plants differ in many respects with non-clonal plants. In order to understand the effects of clonal growth on plant adaptability,in this study a comparative study of clonal plants with nonclonal plants in the genus Veronica was carried out from a phylogenetic perspective. The results showed that clonality is not a conservative trait,and the ancestor of the genus Veronica is likely to be a clonal plant,whose probability is 0. 94. Investment on nutrition structure of clonal plants of genus Veronica is higher than that of non-clonal plant so as to stably supply resources to reproductive structures during flowering and increase the number and size of flowers. Thus they are more attractive to pollinators. Reproductive structures of non-clonal plant undertake the task of absorbing resources. For example： leaf-like bracts can carry out photosynthesis to supply neighboring flower resources. In addition,flowering interval is longer in non-clonal plants than in clonal plants. This strategy ensures to open flowers to get basic resources in adverse environments and avoid waste of resources to abortion. In genus Veronica,non-clonal plants have better tolerance to drought and high temperature compared with clonal plants. Clonal reproduction allows persistence of a species in the absence of the capability to complete sexual reproduction which has a high demand on the environmental conditions. However,clonal plants still need to maintain the surviving organizations,such as the underground rhizomes. If the environment becomes more severe,the tolerance strategy will also be eliminated by natural selection. Escape strategy that avoids harsh times by dormant seeds would be a better choice in this situation. It was speculated that aridification favors the annual lifeform with drought-tolerant seeds so as to increase sexual reproduction importance during the evolution of genus Veronica. Then some plants eventually converted into non-clonal plants,which can respond to the changes of local environment.

关 键 词：克隆植物 适应性 婆婆纳属(Veronica) 系统发育信号 祖先状态重建 

分 类 号：Q948[生物学—植物学]