云南石屏蔗区甘蔗白条病菌的分子鉴定

Molecular Identification of the Pathogen Causing Sugarcane Leaf Scald Disease in Shiping,Yunnan Province of China

为明确2023年在云南石屏蔗区发现的疑似甘蔗白条病症状蔗株病原,利用白条黄单胞菌[Xanthomonas albilineans(Ashby)Dowson]特异性引物XAF1/XAR1对32份疑似病样进行PCR分子鉴定。结果表明所有样品都扩增得到大小约578 bp的特异性条带,GenBank登陆号OR495793-OR495802。对所获序列进行同源性和系统进化分析,发现其与白条黄单胞菌Xa-FJ1菌株的三磷酸腺苷结合盒(Adenosine triphosphate-biding cassette,ABC)转运蛋白基因abc(GenBank登陆号:MH709206)的序列一致性为99.8%~100%,且在系统发育树中处于同一进化分支。结合田间症状诊断和分子鉴定结果,确认云南石屏蔗区发生的甘蔗病害为X.albilineans引起的甘蔗白条病,这是云南石屏蔗区首次发现。研究结果为今后甘蔗白条病的有效防控提供了科学依据。

To identify the pathogen of suspected sugarcane leaf scald plants observed in Shiping,Yunnan Province in 2023,the specific primers XAF1/XAR1 of Xanthomonas albilineans(Ashby)Dowson was used to perform PCR molecular identification for 32 suspected samples.The results showed that all samples were amplified a specific band with a size of about 578 bp,and GenBank accession number is OR495793-OR495802.The homology and phylogenetic analysis of the obtained sequences showed that it was 99.8%~100%identical to the sequence of the adenosine triphosphate-biding cassette transporter gene abc(GenBank accession number:MH709206)in X.albilineans strain Xa-FJ1.Then these X.albilineans strains sequences were clustered together into one branch in the phylogenetic tree.Base on the result of symptom diagnosis in the field and molecular identification,the sugarcane disease occurred in Shiping was confirmed to be leaf scald caused by X.albilineans.This is the first occurrence of sugarcane leaf scald disease in Shiping area of Yunnan Province.These results provide a scientific basis for the effective control of sugarcane leaf scald disease in the future.