The role of arbuscular mycorrhizal fungi in the competition between invasive and native plants depends on the soil nitrogen form

Studies show that arbuscular mycorrhizal fungi (AMF) facilitate invasion of alien plants. AMF prefer to take up and transfer more ammonia (NH₄⁺) than nitrate (NO₃⁻) to plants. However, few studies have investigated the response of AMF to soil N forms. Therefore, two invasive and two native plants in the Asteraceae family were selected for a common garden experiment involving different N forms (NH₄⁺vs. NO₃⁻), AMF treatments (−AMF, +AMF, mycelium) and competition conditions (monoculture vs. mixture).

研究表明，丛枝菌根真菌（arbuscular mycorrhizal fungi, AMF）可促进外来植物入侵。AMF更倾向于吸收并向植物转运更多的铵态氮（ammonia, NH₄⁺），而非硝态氮（nitrate, NO₃⁻）。然而，目前鲜有研究探讨AMF对土壤氮素形态的响应。为此，本研究选取菊科（Asteraceae）的2种入侵植物与2种本土植物，开展包含不同氮素形态（NH₄⁺ vs. NO₃⁻）、AMF处理（-AMF、+AMF、菌丝体）以及竞争条件（单种 vs. 混种）的同质园实验。