植物生态学报 ›› 2017, Vol. 41 ›› Issue (4): 439-449.doi: 10.17521/cjpe.2016.0331

• • 上一篇    下一篇

草甘膦对加拿大一枝黄花和伴生植物白茅种间竞争关系的影响

古春凤1,2, 叶小齐2, 吴明2,*(), 邵学新2, 焦盛武2   

  1. 1杭州师范大学生命与环境科学学院, 杭州 310036
    2中国林业科学研究院亚热带林业研究所, 国家林业局杭州湾湿地生态系统定位观测研究站, 浙江富阳 311400
  • 收稿日期:2016-10-27 接受日期:2017-02-28 出版日期:2017-04-10 发布日期:2017-05-19
  • 通讯作者: 吴明 E-mail:hangzhoubay@126.com
  • 基金资助:
    国家林业公益性行业科研专项(201404210)、国家自然科学基金(31400378)、浙江省公益技术研究农业项目(2015C32011)、浙江省-中国林业科学院科技合作重大项目(2015SY01)

Effects of glyphosate on interspecific competition between Solidago canadensis and Imperata cylindrica

Chun-Feng GU1,2, Xiao-Qi YE2, Ming WU2,*(), Xue-Xin SHAO2, Sheng-Wu JIAO2   

  1. 1College of Life and Environment Sciences, Hangzhou Normal University, Hangzhou 310036, China
    and
    2Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Wetland Ecosystem Research Station of Hangzhou Bay, State Forestry Administration, Fuyang, Zhejiang 311400, China
  • Received:2016-10-27 Accepted:2017-02-28 Online:2017-04-10 Published:2017-05-19
  • Contact: Ming WU E-mail:hangzhoubay@126.com

摘要:

大量使用草甘膦防除外来植物将会改变入侵植物与邻近植物之间的相互关系。该文通过分析不同浓度草甘膦对植物生长和种间竞争关系的影响, 以揭示除草剂作用下植物种间关系的变化规律, 为进一步研究草甘膦的生态效应提供理论参考, 为优化农药使用提供数据支持。2016年6至8月, 在国家林业局杭州湾湿地生态系统定位观测研究站, 采用盆栽控制试验方法, 将入侵植物加拿大一枝黄花(Solidago canadensis)和土著植物白茅(Imperata cylindrica)分别进行单独种植和混种种植, 喷施7种浓度的草甘膦后测定植物的生长特征。结果显示: 草甘膦处理显著抑制了加拿大一枝黄花和白茅的生长。随着草甘膦处理浓度升高, 加拿大一枝黄花的株高增长量明显降低、绿叶数不断减少, 0.3-1.5 mL·L-1处理组单种、混种加拿大一枝黄花的绿叶数均随时间呈递增趋势, 而1.8 mL·L-1处理单种、混种加拿大一枝黄花基本枯萎死亡; 白茅的分蘖死亡数和枯萎叶片长均随草甘膦处理浓度递增而不断增长, 0.3-0.6 mL·L-1处理组单种、混种白茅分蘖数和绿叶长度随时间呈增加趋势。草甘膦处理显著影响植物种间竞争关系, 随着处理浓度上升, 混种加拿大一枝黄花和白茅之间的竞争关系不断减弱。种间竞争关系显著影响了加拿大一枝黄花的生物量分配, 面对竞争时加拿大一枝黄花将更多的生物量分配到根部, 因而增加了根冠比; 种间竞争抑制了白茅分蘖数的增加和生物量的积累, 但不影响其植株生物量的分配。草甘膦处理和种间关系的交互作用同样显著影响加拿大一枝黄花和白茅生物量的增加, 但对两种植物根冠比的影响均不显著。结果表明: 不同植物对草甘膦的耐受性不同, 与本土植物白茅相比, 生长能力强的入侵植物加拿大一枝黄花对草甘膦处理具有更强的耐受性; 低浓度草甘膦处理减弱了两种植物之间的竞争关系, 可能会干扰入侵地植物群落的结构和动态。

关键词: 除草剂, 入侵植物, 本地植物, 生长, 种间关系

Abstract:
Aims The extensive use of herbicide to control invasive plants would change the relationship between alien and neighboring plants. In order to provide data for rational use of herbicide and a theoretical reference for further studies on the ecological effects of glyphosate, we explored the variation of the relationship between an invasive plant Solidago canadensis and a native plant Imperata cylindrica when they were sprayed glyphosate.
Methods A replacement series experiment was conducted from June to August 2016 in Wetland Ecosystem Research Station of Hangzhou Bay, State Forestry Administration, to examine the effects of glyphosate at seven concentration levels (0, 0.3, 0.6, 0.9, 1.2, 1.5, 1.8 mL·L-1) on the growth and interspecific competition of S. canadensis and I. cylindrica.
Important findings (1) Glyphosate treatment significantly inhibited the growth of S. canadensis and I. cylindrica (p < 0.05). During the test, cumulative growth of height and leaf number of S. canadensis were apparently reduced with the increase of glyphosate concentration, but the leaf number of S. canadensis treated with 0.3- 1.5 mL·L-1 glyphosate was re-growing with time, while the one treated with 1.8 mL·L-1 was mostly dead. The withering rate of tiller and green leaf of I. cylindrica also significantly increased with the increase of glyphosate concentration, and the growth indices of this plant treated with 0.3-0.6 mL·L-1 were also re-growing with time. (2) Glyphosate treatment significantly affected interspecific competition (p < 0.05), which diminished as the glyphosate concentration increased. (3) Interspecific competition has significant influence on the biomass allocation of S. canadensis (p < 0.05). When facing competition, S. canadensis would allocate more organic matter to root and thus increase the ratio of root to shoot. Competition only inhibited the tiller number and total biomass of I. cylindrica, but insignificantly affected its ratio of root to shoot. (4) The interaction between glyphosate treatment and S. canadensis-I. cylindrica interspecific relationship also significantly influenced the biomass of S. canadensis and I. cylindrica (p < 0.05), but insignificantly affected the root/shoot ratio of two plants. Different plants have different tolerance to glyphosate stress. Compared with native plant I. cylindrica, S. canadensis has stronger tolerance to glyphosate. Low-concentration glyphosate could decrease the competitive intensity between S. canadensis and I. cylindrica, which may disturb the structure and dynamics of plant communities.

Key words: herbicide, invasive plant, native plant, growth, interspecific relationship