J Plant Ecol ›› 2023, Vol. 16 ›› Issue (1): rtac055.DOI: 10.1093/jpe/rtac055

• Research Articles •    

Rhizosphere and root fungal community of the invasive plant Galinsoga quadriradiata changes along its elevational expansion route

Rui-Ling Liu1,†, Wen-Gang Zhang1,†, Benjamin R. Lee2,3,4, Gang Liu1,5,*, Xing-Jiang Song1, Xiao-Yan Chen1, Jia-Bin Zou1, Fang-Fang Huang6 and Zhi-Hong Zhu1   

  1. 1 College of Life Sciences, Shaanxi Normal University, Xi’an 710119, China, 2 Carnegie Museum of Natural History, Pittsburgh, PA 15213, USA, 3 Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15213, USA, 4 Holden Forest and Gardens, Kirtland, OH 44094, USA, 5 National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, Shaanxi Normal University, Xi’an 710119, China, 6 Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization, Guangdong Academy of Forestry, Guangzhou 510520, China

    Corresponding author. E-mail: 2003liugang@163.com
    These authors contributed equally to this work.
  • Received:2021-12-09 Revised:2022-01-15 Accepted:2022-03-26 Online:2022-05-04 Published:2023-02-01

Abstract:

Fungal communities related to invasive plants may change with an elevational gradient, which may affect the performance and invasiveness of invasive plants. Our recent study revealed that root arbuscular mycorrhizal fungi colonization rate of invasive plant Galinsoga quadriradiata decreased with elevation. However, it is unclear whether it is caused by the changes in the fungal community along elevation. To address this issue, we used high-throughput sequencing techniques, functional groupings and linear statistics to examine how fungal communities in the rhizosphere and roots of G. quadriradiata are changed across the elevation in Qinling and Bashan Mountains, China. Our results revealed that species diversity and composition of the rhizosphere and root fungal communities changed along the elevation. The Shannon–Wiener diversity index in the rhizosphere and roots increased and decreased with elevation, respectively. In contrast, the relative abundance of pathotroph in the rhizosphere decreased while it increased in the roots with elevation. These suggest that, when the invasive plant colonizes into high altitudes, it may not suffer from limited rhizosphere fungal symbionts, but rather the ability of the plant to create and maintain these associations decreases. The invader tends to accumulate more pathogenic fungi in the roots, while the dependence on symbiotic fungi is reduced during expansion into higher elevations. These results highlight that the interactions between invasive plants and fungal community substantially change along elevation, and that belowground interactions may be key in our understanding of how invasive plants derive success in stressful, high-elevation environments.

Key words: invasive plants, range expansion, fungal diversity, fungal abundance, symbionts, pathotrophs

摘要:
入侵植物粗毛牛膝菊根际土壤和根系真菌群落会沿海拔扩散路径发生变化
与入侵植物相关的真菌群落可能会随着海拔发生变化,这可能会影响入侵植物的表现和入侵力。我们最近的研究表明,入侵植物粗毛牛膝菊(Galinsoga quadriradiata)的根系AMF侵染率随着海拔的升高而下降。然而,尚不清楚这是否与真菌群落沿海拔的变化相关。为此,我们采用高通量测序技术、功能分组和线性分析等方法,研究了秦巴山区的粗毛牛膝菊根际土壤和根系真菌群落组成与结构沿海拔的变化趋势。研究结果表明,粗毛牛膝菊根际土壤和根系真菌群落物种多样性和种类组成随海拔升高发生了显著变化。在根际土壤中真菌群落香农-威纳多样性指数随着海拔升高呈上升趋势,而在根系中则呈下降趋势。同时,在根际土壤中共生真菌的相对丰度随海拔高度没有发生显著变化,而在根系中呈下降趋势;在根际土壤中病原真菌的相对丰度随着海拔呈下降趋势,而在根系中呈上升趋势。这些研究结果暗 示,该种在向研究区域高海拔地区入侵时,土壤共生真菌的供给并不会缺乏,但其与这些真菌之间建立并维持共生关系的能力降低了;在向高海拔扩张过程中,该种倾向于在根系中积累更多的病原真菌,而减少对共生真菌的依赖。这些研究结果说明,入侵植物与真菌群落之间的相互作用会沿着海拔梯度发生显著变化,植物地下部分与真菌的相互作用可能是我们理解外来种如何在高海拔环境中入侵成功的关键。


关键词: 入侵植物, 范围扩张, 真菌多样性, 真菌丰度, 共生菌, 病原菌