Journal of Plant Ecology ›› 2022, Vol. 15 ›› Issue (3): 663-671.DOI: 10.1093/jpe/rtab028

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  • 收稿日期:2020-09-09 修回日期:2020-11-07 接受日期:2021-02-26 出版日期:2022-06-01 发布日期:2022-07-01

Effects of clonal integration on allelopathy of invasive plant Wedelia trilobata under heterogeneous light conditions

Lei Pu1, Lang Cheng1, Ai Li1, Sha Liang1, Qing Wei2, Shulan Wu2, Linxuan He2, Xiangning Xu3, Ningfei Lei1,* and Jinsong Chen2,*   

  1. 1 College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, China, 2 College of Life Science, Sichuan Normal University, Chengdu 610101, China, 3 No. 405 Geological Team, Sichuan Bureau of Geology and Mineral Resources, Chengdu 610066, China

    *Corresponding author. E-mail: 470226504@qq.com (N.L.); cjs74@163.com (J.C.)
  • Received:2020-09-09 Revised:2020-11-07 Accepted:2021-02-26 Online:2022-06-01 Published:2022-07-01

摘要: 异质光照条件下克隆整合对入侵植物南美蟛蜞菊化感作用的影响
植物入侵已成为全球生态系统最严重的威胁之一。当具有克隆生长能力的入侵植物入侵或定殖到新的生境时,它们相互连接的分株可能受到异质光照的影响。在异质光照条件下,克隆整合对入侵植物化感作用的影响尚不清楚。为研究异质光照条件下克隆整合对入侵植物南美蟛蜞菊(Wedelia trilobata) 化感作用的影响,采用两个连续分株的克隆片段进行了盆栽试验。较老的分株暴露在全光下,而年轻的分株则受到20%的全光照。同时,每个克隆片段的年轻分株与目标植株(一个番茄苗)在盆栽中相邻生长。南美蟛蜞菊的两个连续分株之间的匍匐茎设置切断和不切断两种处理。另外,两株番茄幼苗 (一株作为目标植株)在盆栽中相邻生长作为对照。研究结果表明,当与目标植物相邻生长的南美蟛蜞菊分株之间的匍匐茎保持完整时,目标植株的生物量积累、叶片叶绿素和氮含量、叶绿素荧光参数和净光合速率及其根长和活性相较于匍匐茎切断处理显著降低。异质光照条件下连续两个分株之间碳水化合物的运输或共享可以增强20%全光处理下年轻分株的化感作用。克隆整合在异质光照条件下对具有克隆生长能力的入侵植物的入侵或定殖具有重要意义。

关键词: 匍匐茎植物, 克隆整合, 入侵机制, 异质环境, 化感作用

Abstract:

Plant invasion is one of the most serious threats to ecosystems worldwide. When invasive plants with the ability of clonal growth invading or colonizing in new habitat, their interconnected ramets may suffer from heterogeneous light. Effects of clonal integration on allelopathy of invasive plants are poorly understood under heterogeneous light conditions. To investigate the effects of clonal integration on allelopathy of invasive plant Wedelia trilobata under heterogeneous light conditions, a pot experiment was conducted by using its clonal fragments with two successive ramets. The older ramets were exposed to full light, whereas the younger ones were subjected to 20% full light. The younger ramets of each clonal fragment were adjacently grown with a target plant (one tomato seedling) in a pot. Stolon between two successive ramets was either severed or retained intact. In addition, two tomato seedlings (one as target plant) were adjacently grown in a pot as contrast. Compared with severing stolon, biomass accumulation, foliar chlorophyll and nitrogen contents, chlorophyll fluorescence parameters and net photosynthetic rates of the target plants as well as their root length and activity, were significantly decreased when stolon between interconnected ramets of W. trilobata retained intact. Under heterogeneous light conditions, transportation or sharing of carbohydrate between two successive ramets enhanced allelopathy of the young ramets subjected to 20% full light treatment. It is suggested that clonal integration may be important for invasion or colonization of invasive plants with ability of clonal growth under heterogeneous light conditions.

Key words: stoloniferous plant, clonal integration, invasive mechanism, heterogeneous environment, allelopathy