摘要
对外来入侵种喜旱莲子草(Alternanthera philoxeroides(Mart.)Griseb.)在不同土壤氮养分处理中的表型可塑性反应进行了研究。结果表明:土壤中氮养分水平对喜旱莲子草克隆生长有显著影响,如分枝强度、茎节长度随氮含量升高均有不同程度的增加;氮养分最高的处理中根系生物量投资最小,而茎、叶生物量投资最大,对照处理中则表现出根冠比最大。研究结果表明,在不同土壤养分条件下,喜旱莲子草不同表型结构有可能同时对环境选择作出反应,在种群生存与维持、生长、繁殖等功能方面实现种群个体各器官生物量投资的优化配置来适应多样化的环境,以增强其入侵能力。
Phenotypic plasticity in response to different soil nutrients in the invasive species Alternanthera philoxeroides was stuclleCl. The results were as follows: The nitrogen in the soil affected significantly the clonal growth of A. philoxeroides. Branching intensity and internode length increased significantly with the increase of nitrogen content, while root/shoot ratios increased significantly with the decrement of nitrogen content. Allocation of root biomass showed negative correlation with soil nitrogen content significantly, while allocation of stems and leaves decreased significantly with the decrement of nitrogen content. The results indicated that A. philoxeroides had strong plasticity in response to the environments with different soil nutrients contents. A. philoxeroides could respond to selection from environments on several different phenotypic organs simultaneously, and show adaptive plasticity by the optimum biomass allocation, which help it survive, grow and propagate under diverse environments successfully. Phenotypic plasticity may play a critical role in invasion ofA. philoxeroides into new environments.
出处
《生态环境》
CSCD
北大核心
2005年第5期723-726,共4页
Ecology and Environmnet
基金
国家重点基础研究发展规划项目(973项目G2000046803)
长沙理工大学博士启动基金项目(1004054)
关键词
喜旱莲子草
表型可塑性
土壤养分
入侵
Alternanthera philoxeroides
phenotypic plasticity
soil nutrients
invasion