枣疯病植原体新疆分离物16S rDNA基因克隆与序列分析

利用植原体16SrDNA基因保守序列通用引物对新疆阿克苏地区和喀什地区的疑似枣疯病植株总DNA进行常规PCR和巢式PCR检测,分别扩增出1.5kb和1.2kb的特异性片段。对片段进行克隆、序列测定分析及系统发育树构建,结果表明,新疆枣疯病阿克苏分离物和喀什分离物的16SrDNA基因序列同源性极高,达到100%,与16SrⅤ组植原体的同源性达到98.4%以上,并且与16SrⅤ-B亚组中的枣疯病山东莱芜株系、山东龙口株系同源性最高,达到99.5%,因此归属于榆树黄化组16SrⅤ-B亚组。首次报道新疆枣疯病植原体16SrDNA的序列,确定新疆枣疯病植原体的分类地位,为枣疯病的早期诊断和检测提供依据。

Cloning and Sequencing Analysis of 16S rDNA of Phytoplasma with Jujube Witches' Broom in Xinjiang

Using PCR and Nested-PCR assay,the 16S rDNA of phytoplasma of jujube witches’ broom(JWB) in the total DNA extracted from diseased samples in Aksu and Kashi region of Xinjiang was amplified with the universal primer pairs,and a 1.5 kb fragment and a 1.2 kb special fragment were obtained,which not extracted from healthy plants.Then the amplified fragments were cloned,sequenced and analysed.The similarity and phylogenetic analysis showed that the amplified 16S rDNA fragment were closely related to 16S rV group of phytoplasma with a homology rate of more than 98.4%,the two isolates had maximum homology,up to 100%,and shared the highest homology(99.5%) with the strains of JWB-Laiwu Shandong and JWB-Longkou Shandong which belongs to Elm yellows group(16S rV-B subgroup).This paper reports firstly 16S rDNA sequences and classified taxonomic status of JWB phytoplasmas Xinjiang isolates and sets the foundation for early diagnosis and identification of jujube witches’ broom.