生物技术通报 ›› 2026, Vol. 42 ›› Issue (1): 279-293.doi: 10.13560/j.cnki.biotech.bull.1985.2025-0862

• 研究报告 • 上一篇    下一篇

梨火疫病生防菌的筛选、鉴定及防效测定

张蔓1(), 党静波1, 蒋媛2, 位杰2, 邢杰1, 王哲1, 孙黎1()   

  1. 1.石河子大学生命科学学院,石河子 832003
    2.新疆生产建设兵团第二师农业科学研究所,巴音郭楞 841005
  • 收稿日期:2025-08-09 出版日期:2026-01-26 发布日期:2026-02-04
  • 通讯作者: 孙黎,女,博士,教授,研究方向 :植物与微生物互作;E-mail: sunlishz@126.com
  • 作者简介:张蔓,女,硕士研究生,研究方向 :植物与微生物互作;E-mail: 13734136860@163.com
  • 基金资助:
    新疆生产建设兵团重点领域科技攻关项目(2023AB004-03)

Screening, Identification and Efficacy Determination of Biocontrol Bacteria against Pear Fire Blight

ZHANG Man1(), DANG Jing-bo1, JIANG Yuan2, WEI Jie2, XING Jie1, WANG Zhe1, SUN Li1()   

  1. 1.College of Life Sciences, Shihezi University, Shihezi 832003
    2.Agricultural Scientific Institute of 2nd Division of Xinjiang Production and Construction Corps, Bayingolin 841005
  • Received:2025-08-09 Published:2026-01-26 Online:2026-02-04

摘要:

目的 梨火疫病是由解淀粉欧文氏菌(Erwinia amylovora)侵染引起的细菌性病害,对梨和苹果产业构成重大威胁。从山梨(Crataegus cuneata)以及新疆野苹果(Malus sieversii)的枝条内筛选出对E. amylovora具有较强拮抗作用的菌株,为E. amylovora的生物防治提供菌种资源。 方法 采用平板对峙法筛选对E. amylovora具有拮抗效果的菌株,结合生理生化反应、16S rDNA和rpoB基因测序对拮抗菌进行鉴定,确定其分类地位;通过甲醇抽提法获得拮抗菌KX1对E. amylovora具有抑制作用的体外抑菌物质;利用薄层层析(TLC)对活性成分进行分离;采用液相色谱-质谱联用(LC-MS)技术对上清液中脂肽类物质进行鉴定;对菌株KX1的全基因组数据进行生物信息学分析,探究其次级代谢产物基因簇;对库尔勒香梨(Pyrus sinkiangensis Yü)离体叶片、枝条和幼果进行温室防效测定。 结果 分离得到7株对E. amylovora具有较强拮抗作用的菌株,其中KX1的拮抗效果最强,结合生理生化特性、16S rDNA以及rpoB基因序列分析,菌株KX1被鉴定为贝莱斯芽胞杆菌(Bacillus velezensis)。菌株KX1的甲醇提取物中含有脂肽类物质,TLC及LC-MS分析表明脂肽类物质主要是表面活性素(surfactin)。脂肽粗提物在不同温度、pH以及储存时间处理后均能保持抑菌活性。菌株KX1的基因组大小为4.1 Mb,GC含量为46.33%。antiSMASH预测到1个次级代谢产物基因簇与丰原素相关的基因簇同源性为80%。温室防效测定结果表明,接种菌株KX1后,库尔勒香梨的幼果、叶片及枝条在保护性试验中的病情指数均显著降低,其防效分别为100%、55.33%和70.65%,且保护性防效优于治疗性防效。 结论 贝莱斯芽胞杆菌KX1能有效抑制E. amylovora的活性,具有一定的生防潜力。

关键词: 梨火疫病, 拮抗菌, 贝莱斯芽胞杆菌, 生物防治, 防治效果

Abstract:

Objective Pear fire blight, caused by Erwinia amylovora, is a destructive bacterial disease causing a significant threat to pear and apple industries. This study aimed to screen strains with strong antagonistic activity against E. amylovora from the branches of Crataegus cuneata and Malus sieversii, providing microbial resources for the biological control of E. amylovora. Method The plate confrontation method was applied to screen the antagonistic strains against E. amylovora. The physiological and biochemical tests, 16S rDNA and rpoB gene sequencing were to determine the taxonomic status of these antagonistic strains. The methanol extractionwas to obtain in vitro antibacterial substances inhibiting E. amylovora. Thin-layer chromatography (TLC) was used to separate active components, and liquid chromatography-mass spectrometry (LC-MS) was used to identify the lipopeptide types in the fermentation broth. Bioinformatics analysis was conducted on the whole-genome data of KXI strain to explore its secondary metabolite gene clusters. The greenhouse control efficacy was tested on detached leaves, twigs, and young fruits of Korla fragrant pear (Pyrus sinkiangensis Yü). Result Seven strains with strong antagonistic activity against E. amylovora were isolated, among which KX1 showed the strongest antagonistic effect. Based on physiological and biochemical characteristics, 16S rDNA and rpoB gene sequence analysis, strain KX1 was identified as Bacillus velezensis. Preliminary detection revealed that the methanol extract of the B. velezensis KX1 contained lipopeptides, and TLC and LC-MS analysis revealed that surfactins were the major component of the lipopeptides. The crude lipopeptide extract retained antibacterial activity after treatments with different temperatures, pH values, storage times. The genome of strain KX1 was 4.1 Mb in size with a GC content of 46.33%. antiSMASH predicted that one secondary metabolite gene cluster shared 80% homology with the gene cluster related to fengycin. Greenhouse control efficacy tests showed that the disease index of immature Korla fragrant pear young fruits, leaves, and twigs in the protective experiment significantly reduced after inoculation with strain KX1. The disease prevention effects was 100%, 55.33%, and 70.65%, respectively, with protective efficacy being superior to therapeutic efficacy. Conclusion Bacillus velezensis KX1 effectively inhibit the activity of E. amylovora and has potential for biological control applications.

Key words: pear fire blight, antagonistic bacteria, Bacillus velezensis, biological control, control efficacy