Chin J Plant Ecol ›› 2020, Vol. 44 ›› Issue (7): 782-790.DOI: 10.17521/cjpe.2020.0114

• Research Articles • Previous Articles    

Nitrogen-fixing bacteria alleviates competition between arbuscular mycorrhizal fungi and Solidago canadensis for nutrients under nitrogen limitation

PANG Fang1, XIA Wei-Kang1, HE Min1, QI Shan-Shan2, DAI Zhi-Cong1,2,*(), DU Dao-Lin1   

  1. 1 School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China
    2 Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, School of Agricultural Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China
  • Received:2020-04-21 Accepted:2020-06-12 Online:2020-07-20 Published:2020-06-23
  • Contact: DAI Zhi-Cong: ORCID:0000-0002-0748-8059,
  • Supported by:
    National Natural Science Foundation of China(31700342);National Natural Science Foundation of China(31770446);China Postdoctoral Science Foundation(2017T100329);Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)


Aims Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with most terrestrial plants, contributing to the nutrient uptake of host plants. While little is known on how rhizospheric microorganisms affect the relationships between AMF and host plants under nutritional stress. We hypothesize that AMF may compete for nutrients with host plants in extremely nutrient-limited environments, such as nitrogen deficient habitats, and nitrogen-fixing bacteria will alleviate the competition.
Methods In order to test our hypotheses, we grew Solidago canadensis plants under nitrogen deficient treatments. We inoculated plants with AMF and a nitrogen-fixing bacterium to test the relationships among the host plant and microorganisms.
Important findings Under the lowest nitrogen level (0.025 mmol·L-1 N of ammonium nitrogen), the growth of S. canadensis was more restricted with AMF colonization, suggesting competition between AMF and the host. However, with the inoculation of nitrogen-fixing bacterium, AMF colonization was promoted and plant growth was increased. These results indicate that nitrogen-fixing bacteria could moderate the competition for nutrients between AMF and their host under nitrogen deficiency. This study improves our understanding of the invasion mechanisms of alien plants, where they interact with different microorganisms under extreme nutrient stress.

Key words: arbuscular mycorrhizal fungi, nitrogen limitation, nutrients competition, nitrogen-fixing bacteria, invasive plant