广西喀斯特地区毛唇芋兰根内与根际土壤真菌群落组成分析

Analysis of fungal communities in roots and root-associated soil of Nervilia fordii from karst areas of Guangxi

关键词:  毛唇芋兰, 菌根真菌, 高通量测序, 真菌多样性, FUNGuild

Key words:  Nervilia fordii, mycorrhizal fungi, high-throughput sequencing, fungal diversity, FUNGuild

摘要:

为探索兰科(Orchidaceae)植物毛唇芋兰(Nervilia fordii)根内和根际土壤真菌群落多样性,该研究采用Illumina MiSeq高通量测序技术,分析了大新(DX)和龙州(LZ)两个样地(简称两地)毛唇芋兰根内和根际土壤的真菌组成。结果表明:(1)两地的毛唇芋兰根内和根际土壤真菌多样性很丰富,根际土壤真菌多样性均高于根内,主根的真菌多样性高于走茎。(2)通过测序共获得有效序列118 040条,207个可操作分类单元(OTUs)涉及8门19纲42目86科123属。(3)担子菌门(Basidiomycota)真菌是两地毛唇芋兰根内真菌的共同优势菌群,涉及胶膜菌科(Tulasnellaceae)、Trimorphomycetaceae、角担菌科(Ceratobasidiaceae)、马拉色菌科(Malasseziaceae)和小皮伞科(Marasmiaceae)等,其中优势科和优势属分别是胶膜菌科(75%)和瘤菌根菌属(Epulorhiza)(56%),而土壤中的优势菌属则是镰刀菌属(Fusarium)。综上认为,毛唇芋兰根内与根际土壤中的优势菌群既差异显著也存在一些共同的OTUs,同时该研究结果暗示Epulorhiza真菌可能对毛唇芋兰种子萌发和种苗生长发育产生至关重要的影响。

Abstract:

To explore the fungal community diversity in the roots of Nervilia fordii as well as in the root-associated soil, we collected the terrestrial orchids grown in Daxin(DX)County and Longzhou(LZ)County of the karst areas in Guangxi Zhuang Autonomous Region, China as well as the root-associated soil, respectively. We analyzed the composition of fungal communities in the roots and the root-associated soil by taking the Illumina MiSeq high-throughput sequencing technology. The results were as follows:(1)The fungal diversity in the roots and root-associated soil of DX and LZ were very rich. In addition, the diversity of fungi in root-associated soil was higher than that in roots, and the fungal diversity in the taproot was higher than that in walking stem.(2)A total of 118 040 valid sequences and 207 operational taxonomic unites(OTUs)were obtained. The BLAST results showed that these OUTs involved 8 phyla, 19 classes, 42 orders, 86 families and 123 genera.(3)The dominant fungal communities in roots of two areas(DX and LZ)both were Basidiomycota including Tulasnellaceae, Trimorphomycetaceae, Ceratobasidiaceae and Malasseziaceae as well as Marasmiaceae. Among them, Tulasnellaceae(75%)and Epulorhiza(Sexual type: Tulasnella)(56%)were the dominant family and genus, respectively. However, Fusarium was the dominant fungal genus in the root-associated soil. In conclusion, there is a significant difference in fungal communities between roots and root-associated soil, but there is some common OTUs. More importantly, our results also suggest that these fungi species belonging to Epulorhiza may play an important effect on the seed germination and seedling growth of Nervilia fordii grown in the karst area of Guangxi.