Abstract:
Objective The interaction of soil community and plant might has a major role in the invasion process of exotic plants. The exploration of the role of plant-soil feedback in the invasion of A. tauschii were examined to provide a theoretical basis for scientific of invasion mechanism.
Method The target community soil was invaded by A. tauschii and its influence on soil nutrient availability was studied. Meanwhile, the feedback function of the invaded community soil on the seed germination and the seedling growth of A. tauschii and wheat, which was the primary accompanying plant, was studied via seed germination and the pot control experiment.
Result The invasion of A. tauschii. decreased nutrient content of the invaded soil, wherein during the heavy invasion, total potassium, nitrate nitrogen, ammonium nitrogen, and available phosphorus in the invaded community soil decreased significantly (P < 0.05) compared with those in the bare soil. The influence of the invaded community soil on the germination of A. tauschii seeds was relatively significant and exhibited a positive feedback function. However, the influence on wheat seed germination was little. The residue of soil allelochemicals or factors of the soil fertility decreased, hence, the negative feedback of the invaded community soil on the wheat growth dominated. However, different from these, soil fungi exhibited the dominant positive feedback on the increase in A. tauschii seedling height as well as on the accumulation of the leaf biomass and total biomass.
Conclusion The invasion of A. tauschii decreased the soil nutrient content, changed soil fungi and allelopathy, created a soil habitat favorable for its own seed germination as well as seedling growth, and enhanced the competitive advantages of the accompanying plant. Thus, the positive plant-soil feedback promoted the invasion and the diffusion of A. tauschii.