摘要
以匍匐茎草本克隆植物积雪草(Centella asiatica) 为材料进行盆栽试验,研究了克隆整合特性对异质性盐分胁迫条件下植物生长的影响。试验中将远端分株 ( 较幼分株) 分别处于盐分胁迫或正常土壤条件下,切断或保持其与近端分株 ( 较老分株) 间的匍匐茎连接。结果表明: 盐分胁迫下,克隆整合提高了受胁迫远端分株和整个克隆片断的叶面积和生物量等生长指标; 与未遭受盐分胁迫处理相比,匍匐茎连接处理导致远端分株的根冠比显著降低。克隆整合还减轻了盐分胁迫对分株的叶绿素含量和光化学效率的影响,但盐分胁迫下,匍匐茎连接处理远端分株的净光合速率与匍匐茎切断处理远端分株并无显著差异,连接受胁迫的远端分株并没有引起近端分株生物量的明显损耗以及光合速率的补偿性提高。总之,克隆整合促进了积雪草遭受盐分胁迫的分株和整个克隆片段的生长,这对于丰富和发展异质性环境胁迫下克隆植物的生态适应对策具有重要意义。
We conducted a pot experiment to study the effects of clonal integration on growth of Centella asiatica suf-fering from heterogeneous saline stress. Distal ramets （younger ramets） of C. asiatica were subjected to high saline or normal soil, and their connections to the proximal ramets （older ramets） were either severed or not. The results demonstrated that, clonal integration was beneficial to the growth of distal ramets and the whole clonal fragments, in terms of leaf area and biomass, and the root to shoot ratio of stolen connection is significantly lower than control. Clonal integration also significantly increased the chlorophyll content and photochemical efficiency of the stressed dis- tal ramets. But, when suffering from saline stress, it has no significant difference between stolon connection and sto-lon severed distal tamers on net photosynthetic rate. Connecting to the stressed distal ramets brought little cost to the proximal ramets, and never incur the increase of photosynthetic efficiency of proximal tamers. In a word, clonal in-tegration improved the growth of the whole clonal fragments in heterogeneous saline stress, it is important for develo-ping the adaptive strategy of clonal plants in heterogeneous environment.
出处
《植物分类与资源学报》
CAS
CSCD
北大核心
2013年第1期55-61,共7页
Plant Diversity
基金
国家自然科学基金(31170502)
四川省科技厅应用基础项目(2011JYZ021)
四川省教育厅重点项目(11ZA033)
关键词
积雪草
克隆整合
盐分胁迫
净光合速率
Centella asiatica
Clonal integration
Saline stress
Net photosynthetic rate
