北京地区番茄黄化曲叶病病毒分离物测定及株系的初步鉴定

 番茄黄化曲叶病毒病是番茄生产中的一种毁灭性病毒病害,2009年传入北京。利用烟粉虱传双生病毒简并引物PA/PB对2010年~2011年采集自北京市5个区县的53个番茄样品进行检测,30个表现典型黄化曲叶病症状的样品均扩增得到约500 bp的特异条带,测定了其中7个样品的部分序列,经序列比对分析表明其为番茄黄化曲叶病毒（Tomato yellow leaf curl virus, TYLCV）。利用TYLCV特异引物TJ-F/TJ-R、TY-F/TY-R对样品BJDXXY、BJFS02、BJFS03、BJMY2231进行TYLCV基因组克隆和序列测定,经分析4个样品携带的TYLCV基因组长度均为2 781碱基,编码6个蛋白。基因组序列比较发现,这4个分离物与TYLCV-Israel株系同源性达到98%以上;通过建立系统发育树,发现BJDXXY、BJFS02、BJFS03与河北分离物（HBLF4）、山东分离物（SDSG）亲缘关系较近,BJMY2231与上海分离物（TYLCV-Israel）、江苏分离物（JSNJ1）亲缘关系较近。

Detection and preliminary strain identification of the pathogen induing Tomato yellow leaf curl disease in Beijing

Tomato yellow leaf curl virus (TYLCV) induces severe disease on tomato and was found in Beijing in 2009.In 2010 and 2011,53 tomato samples from 5 counties were collected and detected using a pair of primers PA/PB designed according to the specific sequence of the whitefly-transmitted geminiviruses. The results showed that target fragment (about 500 bp) could be detected in 30 samples with typical yellow leaf curl symptom. Sequence analysis of the fragments of seven typical samples confirmed that those samples were infected by TYLCV. Complete genomic sequences of 4 TYLCV isolates（BJDXXY,BJFS02,BJFS03 and BJMY2231）were obtained with two pairs of TYLCV-specific primers,TJ-F/TJ-R and TY-F/TY-R.Their genomes all contained 2 781 bp nucleotides encoding six potential proteins and was most closely related to TYLCV-Israel strain (higher than 98% sequence identity).Phylogenetic analysis based on the DNA genome sequence showed that BJDXXY,BJFS02 and BJFS03 were more related to reported isolates of TYLCV-Israel in Hebei Province (TYLCV-HBLF4) and Shandong Province (TYLCV-SDSG）in China,and BJMY2231 is more closely related to the isolates in Shanghai and Jiangsu Province (TYLCV-JSNJ1).