四川斑竹丛枝病植原体检测及16S rDNA片断序列分析

丛枝病是竹子的一类常见的重要病害,除瘤座菌外,很多报道认为植原体也是丛枝病的病原。笔者提取斑竹丛枝部位和健康组织中的总DNA,选用通用引物对植原体的16S rRNA基因进行巢式PCR扩增,得到一条约1.2kb的目的片段,而在健康植株内却没有此特异片断,表明患病植株中有植原体存在,将此植原体株系命名为PhB-WB。通过16S rDNA片断核酸序列同源性比较,结果表明斑竹丛枝病植原体是一种属于16SrⅠ组的植原体,基本确定了其分类地位。

Detection of Phytoplasma in Witches' Broom of Phyllostachys bambusoides and Sequence Analysis of Its 16S rDNA Fragment

Witches’broomis a destructive disease for bambooforest,which causes malformation of thecul ms and affects cul mproduction.It is consideredthat switch’broomof bamboois caused by Balansiatake.In some reports phytoplasma was observedinthe phloemsieve elements by electron microscope.DNAis extractedfrominfectedtissues andit’s healthy counterparts.Nested polymerase chainreaction(PCR) by using a combination of two phytoplasma-specific ‘universal’pri mer pairs(R16mF2/R16mR1-R16F2/R16R2) amplified 16SrRNAfragment(about 1.2 kb) frominfectedtissues but notfromhealthy tissues.The result indicates the existence of phytoplasma associates withthis disease andthis phytoplasmais designated as PhBWB.By comparing homology of nucleotide sequences of amplified16SrDNAfragment the result shows that phytoplasma ofPhyllostachys bambusoidesF.witches’broom(PhBWB) is closely related to Aster yellows(AY).Therefore,it is esti mated that PhBWBisone of the phytoplasma of 16SrⅠgroup.