海南长春花小叶病植原体16S rDNA基因片段的比较分析

从海南儋州地区的长春花上采集了表现小叶症状,疑似植原体感染的病样,利用植原体165 rDNA通用引物对R16mF2/R16mR1,应用PCR技术从该样品的总DNA提取物中扩增到预期大小的特异片段(约1.4kb),该片段的序列分析及系统关系树构建的结果表明,该片段与16Sr Ⅰ组中的植原体同源率均达到99%以上,而与其它组的植原体16S rDNA序列的同源率均低于96%,与16Sr Ⅰ组植原体缬草黄化、翠菊黄化、桑萎缩和玉米丛矮等在同一条进化枝上.故初步认为引起海南长春花小叶病的植原体应归属于16Sr Ⅰ组,将其暂命名为长春花小叶植原体海南株系(Periwinkle little leaf phytoplasma strain Hainan,PLL-Hn).

Sequence Analysis of 16S Ribosomal DNA of Phytoplasma Associated with Periwinkle Little Leaf Disease in Hainan

Periwinkle(Catharanthus roseus) with symptoms of little leaf disease associated to phytoplasma infection was collected in Danzhou, Hainan Province. An amplification product of the expected size (1.4 kb) was observed in the symptomatic periwinkle. Sequence analysis of the fragment of 1 432 bp of the 16S rDNA with primers Rl6mF2/Rl6mR2 indicated that the amplified 16S rDNA fragment was closely related to that from Barley deformation, Aster yellows, Valeriana yellows, Mulberry dwarf, et al. which is believed to be listed in the 16Sr I group. This sample was tentatively named periwinkle little leaf phytoplasma strain Hainan (PLL-Hn).