Zhang Qian, Sun Qixiang, Koide Roger T, Peng Zhenhua, Zhou Jinxing, Gu Xungang, Gao Weidong, Yu Meng
Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China ; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Beijing 100091, China.
Department of Biology, Brigham Young University, Provo, UT 84602, USA.
ScientificWorldJournal. 2014 Feb 12;2014:923610. doi: 10.1155/2014/923610. eCollection 2014.
Obligate aerobic AMF taxa have high species richness under waterlogged conditions, but their ecological role remains unclear. Here we focused on AM fungal mediation of plant interactions in a marshland plant community. Five cooccurring plant species were chosen for a neighbor removal experiment in which benomyl was used to suppress AMF colonization. A Phragmites australis removal experiment was also performed to study its role in promoting AMF colonization by increasing rhizosphere oxygen concentration. Mycorrhizal fungal effects on plant interactions were different for dominant and subdominant plant species. AMF colonization has driven positive neighbor effects for three subdominant plant species including Kummerowia striata, Leonurus artemisia, and Ixeris polycephala. In contrast, AMF colonization enhanced the negative effects of neighbors on the dominant Conyza canadensis and had no significant impact on the neighbor interaction to the dominant Polygonum pubescens. AM colonization was positively related to oxygen concentration. P. australis increased oxygen concentration, enhanced AMF colonization, and was thus indirectly capable of influencing plant interactions. Aerobic AM fungi appear to be ecologically relevant in this wetland ecosystem. They drive positive neighbor interactions for subdominant plant species, effectively increasing plant diversity. We suggest, therefore, that AM fungi may be ecologically important even under waterlogged conditions.
专性需氧的丛枝菌根真菌（AMF）类群在渍水条件下具有较高的物种丰富度，但其生态作用仍不清楚。在此，我们聚焦于沼泽地植物群落中AM真菌对植物相互作用的介导作用。选择了五种共生植物物种进行邻体去除实验，其中使用苯菌灵抑制AMF定殖。还进行了芦苇去除实验，以研究其通过增加根际氧浓度促进AMF定殖的作用。菌根真菌对优势和亚优势植物物种的植物相互作用影响不同。AMF定殖对三种亚优势植物物种（包括鸡眼草、益母草和多头苦荬菜）产生了正向邻体效应。相比之下，AMF定殖增强了邻体对优势植物加拿大飞蓬的负面影响，对优势植物毛蓼的邻体相互作用没有显著影响。AM定殖与氧浓度呈正相关。芦苇增加了氧浓度，增强了AMF定殖，因此间接能够影响植物相互作用。需氧AM真菌在这个湿地生态系统中似乎具有生态相关性。它们对亚优势植物物种产生正向邻体相互作用，有效增加了植物多样性。因此，我们认为即使在渍水条件下，AM真菌可能也具有重要的生态意义。
