广西北海蔗区甘蔗白条病发生情况调查

Sugarcane leaf scald disease in sugarcane planting areas of Beihai,Guangxi

【目的】对广西北海蔗区疑似发生甘蔗白条病的样本进行PCR检测鉴定,明确甘蔗白条病在广西北海的发生情况,为甘蔗白条病的防控提供科学依据。【方法】2016年11月,在广西北海合浦县、银海区和铁山港区采集疑似甘蔗白条病样本372份,涉及19个甘蔗品种/系,采用甘蔗白条病病原白条黄单胞菌[Xanthomonas albilineans(Ashby)Dowson]特异引物XAF1和XAR1对采集样本的DNA进行PCR检测。对部分有阳性条带的PCR产物进行切胶回收,并送样测序,然后在NCBI上进行BLAST比对分析。【结果】所采集的372份样本中,有78份样本扩增出目的条带,阳性检出率为20.97%;19个甘蔗品种中,有13个品种检测出阳性条带,检出率为68.42%,其中白叶病检出率较高的是柳城07-95、桂糖46号、桂糖42号和柳城07-536,检出率分别为75.00%、68.75%、48.15%和33.33%。部分阳性条带经克隆后测序,在NCBI上进行BLAST比对分析,发现其与广西白条病分离物KY315212.1的同源性为99%,表明它们均属于甘蔗白条病基因片段序列。【结论】甘蔗白条病已在广西北海蔗区发生危害,今后需加强检疫工作,防止从疫区调运感病蔗种,以控制病害进一步扩散蔓延。

【Objective】Sugarcane with suspected leaf scald disease in Beihai sugarcane fields in Guangxi were identified by PCR test to determine whether the disease occurs in Beihai,Guangxi,and to provide scientific basis for the controlof sugarcane leaf scald.【Method】In November,2016,372sugarcane samples with suspected leaf scald disease in Hepu County,Yinhai District and Tieshangang District of Beihai,Guangxi were collected,which belonged to19varieties/lines.PCR test was conducted on DNA of the samples collected using specific primers XAF1and XAR1of Xanthomonas albilineans(Ashby)Dowson(pathogeny of sugarcane leaf scald).PCR products with positive bands were recovered and sequenced,than BLAST comparison of the results were conducted in NCBI.【Result】In the372samples,there were78samples amplified target bands with positive detection rate being20.97%.Out of19sugarcane varieties,13ones had target band with positive detection rate being68.42%.The sugarcane varieties with high positive detection rate of sugarcane leaf scaldwere Liucheng07-95(75.00%),Guitang46(68.75%),Guitang42(48.15%),Liucheng07-536(33.33%).Partial positive bands were cloned and sequenced,then BLAST comparison of their sequences were conducted in NCBI.The results showed that they had99%homology with the Guangxi leaf scald disease isolate KY315212.1,which confirmed that they belonged to leaf scald disease gene fragment sequences.【Conclusion】Sugarcane leaf scald disease occurs in Beihai,Guangxi.Therefore,quarantine must be strengthened and diseased sugarcane cannot be transported from infected area to prevent the further spread of the disease.