12种寄主来源的茄科雷尔氏菌16S-23SrDNA间隔区序列比较

应用PCR方法，获得了分离自广东番茄、茄子、辣椒、烟草、空心菜、沙姜、姜、马铃薯、花生、菊花、桑树和藿香等12种作物21个茄科雷尔氏菌菌株的16S 23S rDNA 间隔区序列（ITS）。序列分析结果表明，除HZ 1菌株外，其余20个茄科雷尔氏菌菌株ITS序列长均为503 bp，序列间相似性99.2%~100%，序列间差异仅1~4 bp；而HZ 1菌株的ITS序列长为498 bp，与其他菌株的ITS序列相似性为95.4%~95.6%。这些结果说明，这21株来源于12种不同寄主的茄科雷尔氏菌菌株的16S 23S rDNA ITS序列比较保守。系统进化分析显示，仅菌株HZ 1聚类于茄科雷尔氏菌区组2中，其余20个菌株均聚类于茄科雷尔氏菌区组1中。

Sequence analysis of 16S-23S rDNA intergenic spacer region of Ralstonia solanacearum strains from 12 host plants

The 16S-23S rDNA internal transcribed spacer sequences(ITSs)were amplified by PCR from 21 strains of Ralstonia solanacearum isolated from tomato,eggplant,tobacco,capsicum,Ipomoea aquatica,Kaempferia galangal,ginger,potato,peanut,chrysanthemum,Morus alba and patchouli in Guangdong Province.The ITSs of 20 among the 21 strains,except the strain HZ-1,were determined to be 503 bp in length,and their sequence simi1arity ranged from 99.2%to 100%.The ITS of HZ-1 was determined to be 498 bp in length,and the sequence similarity between HZ-1 and the other 20 strains ranged from 95.4%to 95.6%.These results indicated that 16S23S rDNA ITSs of R.solanacearum isolated from 12 host plants were highly conserved.Phylogenetic analysis showed that the strain HZ-1 Was clustered in the division 2 of R.solanacearum,while the other 20 straim in the division 1 of R.solanacearum.