短短芽胞杆菌多态性分析及产挥发性物质生防菌株筛选

车建美 刘国红 陈倩倩 刘丹莹 刘波

摘 要：为研究不同地区分离的短短芽胞杆菌菌株的多样性特征，并筛选产挥发性物质生防菌株，采用REPPCR、BOXPCR和ERICPCR对短短芽胞杆菌进行遗传多样性分析;同时，采用二分隔平板进行产挥发性物质生防菌株的筛选。结果表明：采用BOX、ERIC和REP引物可以扩增出11～15条较亮、较稳定的条带，多态性比率分别达到85.71%、93.33%和90.91%，表明不同地区分离的菌株基因组存在丰富的遗传多样性。系统聚类分析结果表明，当λ=4.02时，可将20株短短芽胞杆菌菌株分为3个类群，其中来源青海的75%菌株都聚集在类群Ⅱ;来源西藏的75%菌株都聚集在类群Ⅲ中的第1个亚群;来源福建漳州的菌株都聚集在类群Ⅲ中的第2个亚群。采用二分隔平板筛选到5株短短芽胞杆菌，其产生的挥发性物质对龙眼焦腐病菌FJAT3586具有显著的抑制作用，其中菌株FJAT18569和FJAT18570的抑菌率分别为62.80%和59.85%。本试验为研究短短芽胞杆菌多态性提供一定的依据，并为扩充采后水果病害生物防治微生物资源奠定基础。

关键词：短短芽胞杆菌;REPPCR;挥发性物质;遗传多样性

中图分类号：S 476.1 文献标志码：A 文章编号：0253-2301（2021）01-0001-08

DOI：10.13651/j.cnki.fjnykj.2021.01.001

Abstract：In order to study the diversity characteristics of Brevibacillus brevis strains isolated from different areas and to screen the biocontrol strains which produce volatile substances， the genetic diversity of Brevibacillus brevis strains was analyzed by using REPPCR， BOXPCR and ERICPCR， and the biocontrol strains which produced volatile substances were screened by using two-compartment plates. The results showed that 11-15 bright and stable bands could be amplified with BOX， ERIC and REP primers， and the polymorphism rates reached 85.71%， 93.33% and 90.91%， respectively， indicating that there were rich genetic diversity in the genomes of Brevibacillus brevis strains isolated from different regions. The hierarchical cluster analysis results showed that：20 strains of Brevibacillus brevis could be divided into three groups when λ=4.02. Of these clusters， 75% of the strains which were collected from Qinghai were gathered in group Ⅱ， 75% of the strains which were collected from Tibet were gathered in the first subgroup of group Ⅲ， and all the strains which were collected from Zhangzhou in Fujian were gathered in the second subgroup of group Ⅲ. By using two-compartment plates， 5 strains of Brevibacillus brevis were screened， by which the volatile substances produced had significant inhibiting effect on Lasiodiplodia theobromae FJAT3586， and the bacteriostasis rates of FJAT18569 and FJAT18570 were 62.80% and 59.85%， respectively. This study provided some basis for studying the polymorphism of Brevibacillus brevis and laid a foundation for expanding the microbial resources for biological control of postharvest fruit diseases.

Key words：Brevibacillus brevis; REP-PCR; Volatile substance; Genetic diversity

短短芽胞桿菌Brevibacillus brevis属于短芽胞杆菌属，能够形成芽孢，具有很强的环境适应力及与土著微生物的竞争力等[1]，广泛分布于植物根际土壤、海水、湿地和淤泥等生态环境中[2]。近年来，不同生境的短短芽胞杆菌被分离出来应用于环保、生防、化工、食品等方面[3-5]。从大庆油田采油厂含油污水中分离筛选得到的短短芽胞杆菌可降解高碳链饱和烷烃，提高油田采收率[6]。……