石斛附生宿主槟榔微生物分离鉴定及优势真菌拮抗关系  

Isolation and Identification of Microbes from Dendrobium Host Areca,and the Antagonistic between Dominant Fungi

作　　者：罗天雄 杨福孙[1] Luo Tianxiong;Yang Fusun(College of Tropical Crops,Hainan University,Haikou,570228)

机构地区：[1]海南大学热带作物学院,海口570228

出　　处：《分子植物育种》2024年第22期7366-7377,共12页Molecular Plant Breeding

基　　金：海南省槟榔产业技术体系岗位科学家委托协议(HNARS2022-1-G3)资助。

摘　　要：本研究旨在探索海南槟榔林下种植石斛的可行性,以及石斛附生是否导致槟榔微生物性病害。通过对同园区未附生及附生金钗石斛的健康槟榔树干上可培养微生物进行分离纯化,并通过16S rRNA/ITS基因双向测序、BLAST比对和构建系统树等手段对菌株进行分子鉴定以及形态鉴定,对细菌、真菌丰度及群落组成进行分析,并设计拮抗试验验证两类环境中的优势真菌间是否存在拮抗。研究表明石斛附生显著(P<0.05)增加了槟榔树皮微生物的丰度,附生前后细菌优势属均为Bacillus,而优势种有所差异,但仍具有较高重合度。槟榔树皮原始环境中真菌优势属为Lasiodiplodia,优势种为Lasiodiplodia theobromae和Lasiodiplodia pseudotheobromae,前者为槟榔根腐病原真菌。石斛附生后优势属为Trichoderma,优势种为Trichoderma asperellum,该菌为农业生防真菌,拮抗试验表明该菌未产生拮抗性化学物质但可通过竞争抑制Lasiodiplodia theobromae。石斛附生对树皮细菌群落影响较小,对真菌群落的影响较大。附生后槟榔树皮上的真菌优势属Lasiodiplodia被Trichoderma替代,附生降低了槟榔病原菌Lasiodiplodia theobromae的丰度,显著增加了树皮表面细菌和真菌丰度,一定程度上改善了槟榔树干上的微生物环境。This study aims to explore the feasibility of planting Dendrobium under the areca forest in Hainan, and whether the epiphytic Dendrobium can cause microbial diseases of areca. Through isolation and purification of culturable microorganisms on the trunk of normal areca and epiphytic D. nobile, and molecular identification of strains by means of 16S rRNA/ITS bidirectional sequencing, BLAST comparison and system tree construction, the abundance and community composition of bacteria and fungi were analyzed, and antagonistic experiments were designed to verify whether there was antagonism between dominant fungi in the two environments. The results showed that the epiphytic growth of D. nobile significantly increased the abundance of areca bark microorganisms(P<0.05).The dominant genus of bacteria before and after epiphytic growth was Bacillus. However, the dominant species were different, but still had high coincidence. The dominant genus of fungi in the original environment of areca bark was Lasodiplodia, and the dominant species were Lasodiplodia theobromae and Lasodiplodia pseudotheobromae. The former is the pathogen of areca root rot. However, after the epiphytic growth of D. nobile, the dominant genus changed to Trichoderma, and the dominant species was Trichoderma asperellum. This fungus is an agricultural biocontrol fungus. Antagonistic experiments showed that this fungus did not produce antagonistic chemicals, but could inhibit Lasiodiplodia theobromae through competition. Epiphyte of D. nobile has a small impact on the bacterial community of the bark, but a large impact on the fungal community. After epiphyte, the dominant genus of fungi on the bark of areca, Lasodiplodia, was replaced by Trichoderma. Epiphyte reduced the abundance of the pathogenic bacteria Lasodiplodia theobromae, significantly increased the abundance of bacteria and fungi on the bark, and improved the microbial environment on the trunk of areca catechu to a certain extent.

关 键 词：植物互作 微生物 群落组成 生防真菌 

分 类 号：S792.91[农业科学—林木遗传育种] S567.239[农业科学—林学] S154.3