土壤微生物增强了外来植物紫茎泽兰对本地植物种的竞争力（英文）

Soil microbes enhance competition ability of the exotic Ageratina adenophora Sprengel against native plant species

【背景】土壤微生物群落对植物种群建立、生长及其营养都起着至关重要的作用,植物入侵进程也可能与植物—土壤微生物互作相关。【方法】在温室条件下,研究了从紫茎泽兰入侵的土壤(IS)和本地植物生长的土壤(NS)中获得的微生物群落对外来杂草紫茎泽兰与本地植物生长及其互作的影响。【结果】接种来自IS接种剂的紫茎泽兰,特别是与黄花苜蓿或狗尾草共同种植时,较接种NS接种剂具有更高的丛枝菌根侵染率。来自IS的接种剂促进了与本地植物狗尾草共同栽培的紫茎泽兰的生长,但这一本地植物种的生长却未受影响。接种IS接种剂的紫茎泽兰抑制了与其临近种植的2种本地植物的生长,而接种NS接种剂时,未受此影响。接种IS接种剂时,所有种植组合中的紫茎泽兰对接种剂均呈正响应;而接种NS接种剂时,单独种植或与黄花苜蓿共同种植的紫茎泽兰对接种剂呈负响应。【结论与意义】存在于紫茎泽兰根周包括丛枝菌根真菌在内的土壤微生物,增强了这一入侵杂草与本地植物种的竞争力,这可能是外来植物入侵的一个重要机理。

The soil microbial community plays an important role in plant establishment,growth and nutrition.Invasion success may be linked to plant-microbe interactions.[Method] Under glasshouse conditions,we compared the effect of soil microbial communities to the growth and interactions between the exotic weed Ageratina adenophora and native plants.The microbial communities were from soil invaded by A.adenophora （IS） vs.that dominated by native weeds （NS）.[Result] A.adenophora which received inoculum from IS had higher arbuscular mycorrhizal colonization rate than that from NS,especially when Medicag.falcata or Setaria viridis grew near A.aderzophora.Microbial inoculum from IS accelerated the growth of A.adenophora,when planted in polyculture with the native plant S.viridis,but the native species growth was not affected.A.adenophora,receiving an inoculum from IS,inhibited the growth of its two neighboring native species,while no such effect was observed when using inoculum from NS.A.adenophora responded positively to the inoculum taken from IS in all planting combinations,but responded negatively to inoculum from NS both in monoculture and in polyculture with M.falcata.[Conclusion and significance] Soil microbes,including arbuscular mycorrhizal fungi present in soil in the thizosphere of A.adenophora enhanced the competiveness of this invasive weed against native species,which may be an important invasion mechanism of exotic plants.