新疆加工番茄上番茄花叶病毒的分子鉴定

从表现花叶、畸形的加工番茄病株上获得分离物xj124,用1对ToMV CP基因引物进行RT-PCR,扩增得到了689 bp的特异性核苷酸片段。将PCR产物插入到克隆载体pMD18-T中再转化到大肠杆菌TOP10。经限制酶酶切鉴定,重组克隆中含有与PCR产物大小相同的689 bp的插入片段。cDNA全序列分析表明,所扩增出的689 bp ToMV CP基因,含1个480 bp开放阅读框架(ORF),编码160氨基酸组成的蛋白,所克隆的基因包含完整的ToMV CP基因。所测得的xj124分离物与国内外已报道的部分ToMV CP基因序列比较,核苷酸同源性高达84.4%~99.8%,氨基酸同源性高达98.7%~100%。因此将该分离物鉴定为番茄病毒病花叶病毒。

Identification on Molecular of Tomato mosaic virus of Processing Tomato in Xinjiang

Xj124 isolate was obtained from naturally infected processing tomatoes with symptoms of mosaic and malformation in Xinjiang.A pair of primers was designed based on ToMV CP gene,and a fragment of about 689 bp was amplified by RT-PCR.The products of PCR were cloned into PMD18-T and transformed into TOP10.The combined clone was identified by restriction enzyme digesting and the nucleotide sequencing.The results showed that the cloned segment was 689 bp and contained one open reading frames(ORF) that was composed of 480 bp nucleotides encoding a coat protein gene of 160 amino acids.Comparison of the nucleotide and amino acid sequences of the full length of CP gene of ToMV xj124 with the corresponding sequences of the part of the ToMV isolates reported showed that the homology is 83.1%-99.1% at nucleotide level,and 99.4%-100% at amino acid level,respectively.From the above results,the xj124 isolate was identified as ToMV.