Abstract:【Objective】 The invasive plant Sphagneticola trilobata has been expanding to higher latitudes and colder regions since it invaded China due to its rapid adaptability to the environment. As a part of the rhizosphere environment, the rhizosphere microbial community plays an important role in plant invasion and resistance to abiotic stress. However, the effect of rhizosphere microorganisms on the cold tolerance of invasive plants remains to be elucidated. It is therefore hypothesized that rhizosphere microorganisms of S. trilobata acclimated to cold stress play an important role in the improved cold resistance of S. trilobata populations to spread to high latitudes (colder regions).【Method】In this study, two populations of S. trilobata from the southernmost (Sanya ) and northernmost (Wenzhou ) regions of China were used as the research objects, and the cold-acclimatized rhizosphere soil microorganisms of these two populations of S. trilobata were used as microbial agents. Afterwards, the feedback effects of rhizosphere soil microorganisms on the cold tolerance of host plants after low temperature acclimation was explored through soil feedback experiments.【Result】 Under low temperature stress, the inoculation of rhizosphere microbial community significantly increased the biomass, root growth, chlorophyll and leaf nitrogen content of S. trilobata. The maximum photochemical efficiency and photosynthetic performance index of S. trilobata were significantly enhanced by inoculation of rhizosphere soil microbial agents domesticated by the northern (Wenzhou) population, and the relative content of anthocyanins was significantly reduced, indicating that it was less affected by low temperature stress. 【Conclusion】 The results showed that S. trilobata could improve its tolerance to low temperature stress by recruiting rhizosphere microorganisms, and the effect of northern populations was better. This indicates that domestication and recruitment of cold-tolerant rhizosphere microorganisms could promote the expansion of S. trilobata to higher latitudes. Moreover, this study provides an explanation for the possible reasons for differential cold tolerance in different populations of S. trilobata from the perspective of rhizosphere microorganisms, and emphasizes the necessity and urgency of strengthening the supervision of the current invasion boundary regions of S. trilobata.