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土壤生物通过植物-土壤的反馈作用调控植物间相互作用和外来植物入侵.因此,探明植物-土壤反馈作用种间差异的形成原因,对于预测土壤生物在植物入侵过程中的作用具有重要价值.近期的研究发现,植物性状可以用于预测植物-土壤反馈作用.同时,研究发现植物入侵也与植物的一些性状相关联,暗示植物-土壤反馈作用通过植物性状与外来植物入侵之间存在关联,但尚缺乏实验证明.鉴于此,本研究选取了3对近缘入侵和本土植物为对象,比较了其植物-土壤反馈作用,探讨了植物-土壤反馈作用与植物根部性状的关联性.首先,通过种植实验植物3个月,驯化采自于田间的土壤.之后,将实验植物种植于对照和灭菌处理的同种或近缘(同科或同属)种驯化过的土壤中,评价同种或近缘种根际土壤生物对植物生长的净反馈作用(与灭菌土比较),并比较了两类土壤生物对植物的反馈作用.总体而言,同种或近缘种根际土壤生物对入侵与本土植物的净反馈作用无显著差异,两类土壤生物对入侵和本土植物的反馈作用亦无显著差异.土壤反馈作用的强度和种植于对照土壤中植物细根生物量比存在正相关关系,且入侵与本土植物细根生物量比无显著差异.这一发现表明:相似的细根生物量比可能是导致入侵与本土植物间土壤反馈作用无差异的一个重要原因.为提升人们对土壤生物在植物入侵过程中作用的认识,亟需选取更多入侵与本土植物(尤其是亲缘关系较远的物种)开展实验研究,进一步探明植物性状、土壤反馈作用和外来植物入侵之间的关联性.“,”Aims Soil biota can affect plant-plant interactions and non-native plant invasions via plant-soil feedback (PSF).Understanding the drivers underlying interspecific variations in PSF is important for predicting the role of soil biota in non-native plant invasions.Recent studies found that PSF could be predicted by plant traits.The success of plant invasions is also linked with plant traits,suggesting a potential linkage between PSF and plant invasion via plant traits,but has not yet been tested.Here,we compared PSF between six phylogenetically paired co-occurring native and invasive plants,and explored the potential linkage between PSF with plant root traits.Methods We conducted a two-phase PSF experiment.Field collected soils were conditioned by the six plant species for 3 months firstly,then seedlings of these plants were grown in living or sterilized soils that had been conditioned by conspecific vs.heterospecific (the congener/confamilial species) individuals.We estimated effects of biota in conspecific (conspecific PSF) or heterospecific (heterospecific PSF) soils relative to sterilized soils,and the relative effects of biota in conspecific vs.heterospecific soils (PSF-away) on plant biomass.Important Findings In general,soil biota suppressed plant growth,and there were no differences in conspecific PSF,heterospecific PSF and PSF-away between native and invasive plants.PSF increased with rising plant fine-to-total root mass ratio in the presence of soil biota,and its value was comparable between native and invasive plants.Our results indicate that similarity in plant fine-to-total root mass ratio that predicted PSF may have partially led to the comparable PSFs between these native and invasive plants.Studies exploring the linkages among plant traits,PSF and plant invasions with more plants,in particular phylogenetically distant plants,are needed to improve our understanding of the role of soil biota in plant invasions.