拮抗水稻病原菌假单胞菌AH菌株的鉴定及全基因组序列分析  

Identification and Whole Genome Analysis of Pseudomonas putida AH Strain Antagonistic to Rice Pathogens

作　　者：胡逸群 沈文杰 陈晴晴 张爱芳 HU Yi-qun;SHEN Wen-jie;CHEN Qing-qing(Institute of Plant Protection and Agro-products Safety,Anhui Academy of Agricultural Sciences,Hefei,Anhui 230001)

机构地区：[1]安徽省农业科学院植物保护与农产品质量安全研究所,安徽合肥230001

出　　处：《安徽农业科学》2023年第20期138-146,共9页Journal of Anhui Agricultural Sciences

基　　金：国家自然科学基金项目(32202273);安徽省自然科学基金项目(2108085QC117)。

摘　　要：[目的]探究菌株AH的生防潜力和基因组序列信息,以解析其防病机制,挖掘次级代谢产物基因资源。[方法]采用稀释涂布平板法分离水稻的叶际微生物,筛选具有拮抗效果的菌株;根据形态学、16S rDNA和gyrB基因测序和系统发育分析,鉴定其种属;利用平板抑菌试验明确其抑菌谱;大田喷施菌悬液明确其防治效果。继而,利用第二代Illumina与第三代PacBio结合的测序方法对生防菌进行全基因组测序,对测序数据进行基因组组装、基因预测与功能注释、次级代谢产物合成基因簇预测等分析。[结果]AH是一株短杆状恶臭假单胞菌株,对稻瘟病菌、茎点霉菌、水稻纹枯病菌和水稻黄单胞菌具有广谱抗菌活性,且田间施用AH菌液可显著降低水稻白叶枯病和稻瘟病的病害等级。抗生素敏感性测试揭示菌株AH对氨基糖苷类抗生素高度敏感。AH基因组全长为5889125 bp,编码5215个基因,GC含量为63.74%,有19个rRNA、77个tRNA和78个nRNA,antiSMASH预测得到8个次级代谢产物合成基因簇。[结论]AH菌株具有良好生防潜力,深层机制解析可为病害防控提供科学依据。[Objective]Biocontrol potential and genome information of strain AH were analyzed to reveal mechanism of disease prevention and explore gene resources of secondary metabolites.[Method]The method of spreading plates was used to screen antagonistic strains from rice leaves.The species was identified by morphological,16S rDNA and gyrB sequencing and phylogenetic analysis.The flat standoff test and spraying bacterial suspension in field clarified its biocontrol potential.Subsequently,the genome sequence of AH strain was obtained using a third generation Pacbio SMRT sequencing platform and second-generation Illumina sequencing technology.Then,genome assembly,gene prediction,function annotation,and secondary metabolite biosynthetic gene cluster prediction were performed.[Result]AH was a short rod strain,belonged to Pseudomonas putida,and showed broad-spectrum antimicrobial activity against Magnaporthe oryzae,Phoma sp.,Rhizoctonia solani,and Xanthomonas oryzae.Spraying AH suspension significantly reduced disease grade caused by bacterial blight and blast disease.Antibiotic susceptibility testing revealed that AH showed high sensitivity to aminoglycoside antibiotics.The total length of AH genome was 5889125 bp,encoding 5215 genes with 63.74%GC content,including 19 rRNA,77 tRNA and 78 nRNA.And,eight secondary metabolite synthesis gene clusters were predicted by antiSMASH platform in AH genome.[Conclusion]Based on good biocontrol potential of AH strain,the analysis of deep mechanism can provide scientific basis for disease prevention and control.

关 键 词：恶臭假单胞AH 生物防治 稻瘟病 水稻白叶枯病 

分 类 号：S435.11[农业科学—农业昆虫与害虫防治]