Changes in soil microbial communities due to biological invasions can reduce allelopathic effects

Summary
1. Soil microbes are important in mediating allelopathic interactions between invasive and native plants in the field. However, it was not known how these interactions vary in the process of biological invasions and the effects of soil microbes. Knowing these may facilitate understanding dynamics and mechanisms of biological invasions and managing invaded ecosystems.
2. We conducted competition and seed germination experiments to determine the allelopathic effects of Ageratina adenophora in soils from 42 sites with varying abundances of the invasive plant. Then we isolated the microbes that had the ability to degrade the allelochemicals of the invasive plant and tested their functions.
3. In both experiments, the allelopathic effects of the invasive plant were much stronger in soils from non-invaded sites than in soils from invaded sites. Activities of the allelochemical-degrading microbes were higher and degradation of the allelochemicals of the invasive plant was fas...

1. 土壤微生物（soil microbes）在介导野外入侵植物与本土植物间的化感相互作用（allelopathic interactions）中发挥着关键调控作用。然而，目前尚不清楚此类相互作用在生物入侵（biological invasions）进程中的变化规律，以及土壤微生物所产生的具体影响。明晰这一科学问题，将有助于深入解析生物入侵的动态过程与内在机制，并为入侵生态系统的科学管理提供理论依据。
2. 本研究采集了42个入侵植物丰度存在差异的样地土壤，开展竞争实验与种子萌发实验，以明确紫茎泽兰（Ageratina adenophora）的化感效应；随后分离出可降解该入侵植物化感物质（allelochemicals）的微生物，并对其功能开展验证。
3. 两项实验均显示，非入侵样地土壤中该入侵植物的化感效应显著强于入侵样地土壤；降解化感物质的微生物活性更高，且入侵植物化感物质的降解过程更快（原文未完整呈现后续内容）。