中国锦紫苏类病毒的检测及其分子生物学特征研究

Detection and molecular characterization of Coleus blumei viroid in China

从无明显症状表现的11株锦紫苏叶片中抽提低分子量的RNA，经Return-PAGE、RT-PCR和Dot-blot hybridization检测，结果表明11株锦紫苏全部带有锦紫苏类病毒（Coleus blumei viroid，CBVd）。将部分PCR产物克隆到pGEM-3Zf（＋）载体上并进行DNA序列测定。序列分析结果，所克隆的序列（GenBank登录号分别为DQ178395、DQ178396、DQ178397、DQ178398和DQ178399）与GenBank中报道的锦紫苏类病毒1号（CBVd—1）序列同源性为85．23％～99．20％。从市场上购买的锦紫苏种子经Return—PAGE和RT-PCR检测不携带锦紫苏类病毒。这是中国发生的锦紫苏类病毒的首次报道。

The low molecular weight RNAs from 11 coleus plants were characterized by Return-PAGE, RT- PCR and Dot-blot hybridization. The results showed that all the 11 coleus plants were infected by Coleus blumei viroid. The amplified products of RT-PCR were cloned into vector pGEM-3Zf （ ＋ ） and sequenced. 5 sequences variants were registered in GenBank DQ178395 ,DQ178396 ,DQ178397 ,DQ178398 and DQ178399, and compared with reported sequences of CBVd-1 in GenBank showing 85.23%- 99.20% identity. No Coleus blumei viroid 1 detected from coleus seeds by RT-PCR and Return-PAGE. This is the first report on the occurrence of CBVd in China.