Abstract：Water fern Azolla is a striking plant-cyanobacteria mutualistic association. N2-fixing cyanobacteria and numerous bacteria have been found within the leaf cavities of Azolla using traditional techniques. The aim of the present study is to explore the genetic diversity of microbial community, particularly fungi and archaea, employing scanning electron microscopy (SEM), fluorescence in situ hybridization (FISH) and high throughout sequencing technique. 250 microbial samples isolated from 120 leaf cavities of fresh and healthy Azolla microphylla fronds were examined with both fluorescence microscopy and electron microscopy. Fungi-like structures, including hyphae, ascus, ascospore, conidium and basidium, were found in 230 samples. Eighty percent of fungi-like structures were positioned in leaf 7th to leaf 15th, indicating the older of leaf age, the more number of fungi detected. Archaea was investigated positively in 86% of the samples, and there was no correlation between the abundance and the leaf age. Through high throughout sequencing both fungi and archaea were identified qualitatively and quantitatively. The results showed that there were Ascomycota(67.39%), Phragmoplastophyta (31.72%), Cordycipitaceae (0.56%), Entomophthoromycota (0.33%), totally 4 fungal phyla, and 2 archaeal phyla with dominance of Euryarchaeota (99.68%) co-existing in Azolla. The results of this study implied that the microecosystem within Azolla was much more complex than we originally thought. It also indicates that Azolla is a valuable model plant for the study of plant-microbe interaction.
陈坚, 郑伟文, 郑益平, 陈彬, 郑斯平, 朱炳耀. 水生植物小叶满江红内生真菌与古菌的发现及基于高通量测序的群落组成分析[J]. 农业生物技术学报, 2019, 27(11): 2063-2072.
CHEN Jian, ZHENG Wei-Wen, ZHENG Yi-Ping, CHEN Bin, ZHENG Si-Ping, ZHU Bin-Yao. Discovery of Endo-Fungi and Archaea Within Water Fern Azolla microphylla and Their Community Analyses Based on High Throughput Sequencing. 农业生物技术学报, 2019, 27(11): 2063-2072.
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