Ristaino Jean Beagle, Johnson Andrea, Blanco-Meneses Monica, Liu Bo
Department of Plant Pathology, North Carolina State University, Raleigh 27695.
Plant Dis. 2007 Jun;91(6):685-691. doi: 10.1094/PDIS-91-6-0685.
Tobacco blue mold, caused by the oomycete pathogen Peronospora tabacina, is a highly destructive pathogen of tobacco (Nicotiana tabacum) seed beds, transplants, and production fields in the United States. The pathogen also causes systemic infection in transplants. We used polymerase chain reaction (PCR) with the primers ITS4 and ITS5, sequencing, and restriction digestion to differentiate P. tabacina from other important tobacco pathogens, including Alternaria alternata, Cercospora nicotianae, Phytophthora glovera, P. parasitica, Pythium aphanidermatum, P. dissotocum, P. myriotylum, P. ultimum, Rhizoctonia solani, Sclerotinia sclerotiorum, Sclerotium rolfsii, Thielaviopsis basicola, and related Peronospora spp. A specific PCR primer, called PTAB, was developed and used with ITS4 to amplify a 764-bp region of DNA that was diagnostic for P. tabacina. The PTAB/ITS4 primers did not amplify host DNA or the other tobacco pathogens and were specific for P. tabacina on tobacco. DNA was detected to levels of 0.0125 ng. The PTAB primer was useful for detection of the pathogen in fresh, air-dried, and cured tobacco leaves. This primer will be useful for disease diagnosis, epidemiology, and regulatory work to reduce disease spread among fields.
烟草霜霉病由卵菌病原体烟草霜霉病菌（Peronospora tabacina）引起，是美国烟草（Nicotiana tabacum）苗床、移栽苗及生产田的一种极具破坏性的病原体。该病原体还会导致移栽苗发生系统性感染。我们使用引物ITS4和ITS5进行聚合酶链反应（PCR）、测序及限制性酶切，以区分烟草霜霉病菌与其他重要的烟草病原体，包括链格孢（Alternaria alternata）、烟草尾孢菌（Cercospora nicotianae）、格氏疫霉（Phytophthora glovera）、寄生疫霉（P. parasitica）、瓜果腐霉（Pythium aphanidermatum）、离壁腐霉（P. dissotocum）、多雄腐霉（P. myriotylum）、终极腐霉（P. ultimum）、立枯丝核菌（Rhizoctonia solani）、核盘菌（Sclerotinia sclerotiorum）、齐整小核菌（Sclerotium rolfsii）、烟草黑胫病菌（Thielaviopsis basicola）以及相关的霜霉属物种。开发了一种名为PTAB的特异性PCR引物，并与ITS4一起用于扩增一段764 bp的DNA区域，该区域可作为烟草霜霉病菌的诊断依据。PTAB/ITS4引物不会扩增宿主DNA或其他烟草病原体，对烟草上的烟草霜霉病菌具有特异性。能检测到低至0.0125 ng水平的DNA。PTAB引物可用于检测新鲜、风干及调制后的烟叶中的病原体。该引物将有助于疾病诊断、流行病学研究以及监管工作，以减少病害在田间的传播。
