【摘要】 应用植原体 16SrRNA基因通用引物,分别对表现矮化和扁茎症状的矮牵牛植株进行巢式PCR检测,均得到约 1. 2kb的特异片段。将此特异片段与pGEM -TEasy载体连接并转化到大肠杆菌JM109感受态细胞中,通过PCR鉴定,序列测定及同源性比较分析,结果表明:这 2个植原体株系 16SrDNA片段G+C含量分别为47. 1%和 47. 0%,具有其他柔膜菌纲原核生物 16SrRNA基因碱基组成特征;与 16Sr组中的代表株系 (西方翠菊黄化,SAY)同源率达到最高,分别为 99. 1和 98. 6%,故认为这 2个株系为该组成员之一。更多还原

【Abstract】 Using universal primers for 16SrRNA gene to detect phytoplasmas in petunia showing stunt and flat stem symptom,respectively,a 1.2 kb DNA fragment was amplified by NestedPCR.The amplified fragment was ligated into pGEMT easy vector and then transformed into the competent cell of E.coli JM109 strain. Cloned DNA fragments were verified by PCR, sequencing and analysis of homology. The result showed that the content of G+C in the 16SrDNA sequences is 47.1% and 47.0% respectively, which possessed the character of 16SrRNA gene from prokaryote in Mollicutes and they all shared high homology (99.1% and 98.6%) with Western Aster yellows, which is a representative phytoplasma strain in 16Sr group. So the result made it clear that the two phytoplasma strains are one of the members of phytoplasma 16Sr group.更多还原