Division of Biology, Kansas State University, Manhattan, KS, 66506, USA.
Mycorrhiza. 2011 Aug;21(6):453-464. doi: 10.1007/s00572-010-0358-7. Epub 2011 Jan 5.
Use of the reverse-transcribed small subunit of the ribosomal RNA (rRNA) was tested for exploring seasonal dynamics of fungal communities associated with the roots of the dominant tallgrass prairie grass, Andropogon gerardii. Ribosomal RNA was extracted, reverse-transcribed, and PCR-amplified in four sampling events in May, July, September, and November. Analyses of cloned PCR amplicons indicated that the A. gerardii rhizospheres host phylogenetically diverse fungal communities and that these communities are seasonally dynamic. Operational taxonomic units with Basic Local Alignment Search Tool affinities within the order Helotiales were dominant in the rhizosphere in May. These putative saprobes were largely replaced by arbuscular mycorrhizal fungi with likely affinities within Glomerales suggesting that the fungal communities are not only compositionally but also functionally dynamic. These data suggest replacement of functional guilds comprised of saprobic fungi by mutualistic fungi in the course of a growing season.
使用核糖体 RNA（rRNA）的逆转录小亚基来探索与优势高草草原草种 Andropogon gerardii 根相关的真菌群落的季节性动态。在 5 月、7 月、9 月和 11 月的四个采样事件中提取、逆转录和 PCR 扩增核糖体 RNA。克隆 PCR 扩增子的分析表明，A. gerardii 根际中存在具有系统发育多样性的真菌群落，并且这些群落具有季节性动态。在 5 月，与 Helotiales 目具有基本局部比对搜索工具亲和力的分类操作单位在根际中占优势。这些推测的腐生物主要被具有 Glomerales 可能亲和力的丛枝菌根真菌取代，这表明真菌群落不仅在组成上而且在功能上都是动态的。这些数据表明，在生长季节过程中，由腐生真菌组成的功能类群被共生真菌所取代。
