Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education & Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark.
Mycorrhiza. 2021 Jan;31(1):93-102. doi: 10.1007/s00572-020-00997-1. Epub 2020 Nov 2.
Arbuscular mycorrhizal fungi (AMF) colonization in roots of putative non-mycotrophic species has been known for decades, but our knowledge of AMF community structure in non-mycotrophic plants is limited. Here, we compared AMF species composition and diversity in roots of co-occurring mycotrophic and putative non-mycotrophic herbs in two wetlands. A SSU-ITS-LSU fragment in AMF rDNA was amplified, cloned and sequenced, and used to characterize the AMF community in the roots of 16 putative non-mycotrophic and 18 mycotrophic herbs. The results showed that AMF hyphae and vesicles, but not arbuscules, were commonly present in putative non-mycotrophic plants. A total of 971 AMF sequences were obtained, and these were finally assigned to 28 operational taxonomic units (OTUs). At both sites, AMF taxon richness and Hill number based on Shannon's index in the putative non-mycotrophic herbs were similar to those for mycotrophic plants, but AMF community composition between mycotrophic and non-mycotrophic plants was significantly different. Ten AMF OTUs were uniquely detected in the putative non-mycotrophic species, and two were identified as the AMF indicators in non-mycotrophic plants. These results implied that non-mycotrophic plants may harbor a potential source of AMF diversity previously ignored which should be included in our understanding of diversity, distribution pattern, and ecological significance of root-colonizing AMF. As the first direct comparison of AMF diversity and species composition between mycotrophic and putative non-mycotrophic species in wetlands, our study has important implications for the understanding of AMF distribution patterns.
丛枝菌根真菌（AMF）在假定非菌根植物根系中的定殖已为人所知数十年，但我们对非菌根植物中 AMF 群落结构的了解有限。在这里，我们比较了两个湿地中同时存在的菌根和假定非菌根草本植物根系中 AMF 物种组成和多样性。扩增、克隆和测序了 AMF rDNA 中的 SSU-ITS-LSU 片段，并用于表征 16 种假定非菌根和 18 种菌根草本植物根系中的 AMF 群落。结果表明，AMF 菌丝和泡囊，但不是丛枝，普遍存在于假定非菌根植物中。共获得 971 条 AMF 序列，最终将其分为 28 个操作分类单元（OTU）。在两个地点，假定非菌根植物中的 AMF 分类丰富度和基于 Shannon 指数的 Hill 数与菌根植物相似，但菌根和非菌根植物之间的 AMF 群落组成存在显著差异。在假定非菌根植物中，有 10 个 AMF OTU 是唯一检测到的，其中两个被鉴定为非菌根植物中的 AMF 指示种。这些结果表明，非菌根植物可能蕴藏着以前被忽视的 AMF 多样性的潜在来源，这应该被纳入我们对根系定殖 AMF 的多样性、分布模式和生态意义的理解中。作为湿地中菌根和假定非菌根物种之间 AMF 多样性和物种组成的首次直接比较，我们的研究对理解 AMF 分布模式具有重要意义。
