关键词: 紫茎泽兰；入侵植物；微生物反馈；PLFAs

Abstract:

The competitive succession of plants community is determined by feedback of interaction between plant and soil microbe. In order to confirm the role of soil microbe in the population establishment and expansion of Ageratina adenophora Sprengel, a vicious invasive weed in china,  the feedback effects of microorganisms in plant rhizosphere soil on growth of Ageratina adenophora Sprengel and 2 native plants were compared, Eupatorium lindleyanum DC. and Setaira viridis (L.) Beauv, by conducting the greenhouse pot experiment. A. adenophora and native plant soil were sterilized, added fungicide and no treated (control groups), respectively. The results showed that soil microorganisms in plant rhizosphere can produce a direct positive feedback effects on the growth of plants. The biomass of A. adenophora, E. lindleyanum and S. viridis decreased significantly after adding fungicide or sterilizing. There were no significant difference of AMF root colonization of E. lindleyanum and S. viridis between A. adenophora soil and native plant soil in control group, but AMF root colonization of E. lindleyanum and S. viridis in A. adenophora soil increased by 81.02% and 89.7% compared to native plant soil after adding fungicide, respectively. The PLFAs results also showed that the soil microbe communities of A. adenophora and native plants were apparently different. It was considered that the invasive plant, A. adenophora produced positive feedback to itself by affecting the soil microbe communities and function in invaded habits, subsequently contributing to its growth and population expansion.

Key words: Ageratina adenophora Sprengel, invasive plant, microbe feedback, PLFAs