Kowalchuk George A, de Souza Francisco A, van Veen Johannes A
Netherlands Institute of Ecology, Center for Terrestrial Ecology, Heteren, The Netherlands.
Mol Ecol. 2002 Mar;11(3):571-81. doi: 10.1046/j.0962-1083.2001.01457.x.
A polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) approach for the detection and characterization of arbuscular mycorrhizal fungi (AMF) 18S ribosomal DNA (rDNA) was developed and applied to the study of AMF communities associated with the main sand-stabilizing plant species of the Dutch sand dunes, marram grass (Ammophila arenaria, L.). DNA was extracted directly from plant roots, soil or isolated AMF spores, and prominent bands resulting from AMF-specific DGGE profiles were excised for sequence analysis. This strategy provided a robust means of detecting and identifying AMF-like species without the use of trap plant cultivation methods. A number of Glomus-like and Scutellospora-like sequences was detected, including a putatively novel Glomus species, and differences were observed in the dominant AMF-like populations detected in healthy vs. degenerating stands of A. arenaria and in bulk sand dune soil. It has previously been suggested that plant pathogens, such as fungi and nematodes, may contribute to the decline of A. arenaria. Although no causal relationship can be drawn between the observed differences in the dominantly detected AMF-like populations and the vitality of plant growth, these results indicate that mutualistic interactions between this plant and AMF should not be overlooked when examining the role of soil-borne microorganisms in vegetation dynamics. In addition, there were discrepancies observed between the AMF-like groups detected in spore populations vs. direct 18S rDNA analysis of root material, corroborating previous suggestions that spore inspection alone may poorly represent actual AMF population structure.
一种用于检测和表征丛枝菌根真菌（AMF）18S核糖体DNA（rDNA）的聚合酶链反应-变性梯度凝胶电泳（PCR-DGGE）方法被开发出来，并应用于研究与荷兰沙丘主要固沙植物物种沙茅草（Ammophila arenaria, L.）相关的AMF群落。DNA直接从植物根系、土壤或分离出的AMF孢子中提取，AMF特异性DGGE图谱产生的显著条带被切下用于序列分析。该策略提供了一种无需使用诱捕植物栽培方法就能检测和鉴定类AMF物种的可靠手段。检测到了一些类球囊霉属和类盾巨孢囊霉属序列，包括一个可能的新球囊霉物种，并且在健康与退化的沙茅草林分以及沙丘整体土壤中检测到的优势类AMF种群存在差异。此前有人提出，植物病原体，如真菌和线虫，可能导致沙茅草数量减少。尽管在主要检测到的类AMF种群差异与植物生长活力之间无法得出因果关系，但这些结果表明，在研究土壤传播微生物在植被动态中的作用时，不应忽视这种植物与AMF之间的互利相互作用。此外，在孢子种群中检测到的类AMF群体与对根系材料进行的直接18S rDNA分析之间存在差异，这证实了之前的观点，即仅通过孢子检查可能无法很好地代表实际的AMF种群结构。
