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采用PCR-DGGE和DNA克隆测序技术对黄土沟壑区一时间演替序列(5、13、20 a和42 a)上的人工柠条林的丛枝菌根真菌(Arbuscular Mycorrhizal Fungi;AMF)进行群落结构及多样性研究。结果显示,所有DNA序列聚为四个均属于AMFGlomus属的序列群,分别与Genbank上已登录的G.intraradices(同源性≥98%)、G.fas-ciculatum(=99%)、Glo18(=98%)和G.sp.(=98%)相关,这表明,在特定的时间点上柠条根系的AMF多样性十分低下。这四个序列群在5～20 a的柠条林中均出现,而在42 a的柠条林中只有G.sp.未出现,这表明,AMF群落组成并未随着柠条林的演替而发生显著改变,即AMF群落并未随着人工柠条林的恢复演替而得到恢复;土壤理化性质的稳定以及人工柠条林中的AMF群落与植被之间的正向反馈关系可能是导致这种现象的主要原因。
The community structure of Arbuscular Mycorrhizal Fungi (AMF) in Artemisia langeus was analyzed by PCR-DGGE and DNA cloning sequencing in the temporal succession sequence (5, 13, 20 a and 42 a) Structure and Diversity Research. The results showed that all the four DNA sequences were clustered into four sequences belonging to the genus AMFGlomus, which were respectively homologous to G.intraradices (≥98% homology), G.fas-ciculatum (= 99%), Glo18 ( = 98%) and G.sp. (= 98%), indicating that there is very low AMF diversity in the roots of the kelp at specific time points. These four sequences appeared in the Caragana forest of 5-20 years, but only G.sp. did not appear in the Caragana forest of 42 years, which indicated that the AMF community composition did not change with the Caragana forest However, the AMF community did not recover with the restoration succession of Artificial Caragana korshinskii. The stability of soil physical and chemical properties as well as the positive feedback relationship between AMF community and vegetation in Artemisia langeus The main reason for this phenomenon.