【作者】 和志娇；

【导师】 陈海如； 蔡红；

【作者基本信息】 云南农业大学 ， 植物病理学， 2006， 硕士

【摘要】 根据植原体16S rRNA基因通用引物序列(R16mF2/R16mRl、R16F2/R16R2)及核糖体蛋白基因(rp)通用引物序列(rpF1/rpR1),应用PCR技术对采自不同省份的苦楝丛枝病植原体进行检测,结果从两个植物上分别获得苦楝丛枝病植原体云南株系(CWB-YN)和贵州株系(CWB-GZh)。对这两个植原体株系的16S rRNA基因和核糖体蛋白基因扩增片段进行克隆和序列测定,结果表明上述两个苦楝丛枝病植原体株系的16S rRNA片段及核糖体蛋白基因片段核苷酸序列均为1248 bp和1242 bp。通过16S rRNA及rp基因的核酸序列同源性比较分析,发现这两个株系间同源率分别达到99.4%和99.8%。苦楝丛枝病植原体云南株系与其它组16S rRNA基因序列的同源率进行比较,结果与16SrI-A组中的番茄巨芽病植原体(Tomato big bug,BB)、16SrI-B组中的西方翠菊黄化病植原体(Western aster yellow,SAY)和16SrI-C组中的三叶草变病植原体(Clover phyllody,CPh)同源率达最高,分别为98.5%、98.9%和98.0%,而与其它组的植原体16S rRNA基因序列的同源率均低于95%;苦楝丛枝病植原体贵州株系与16Sr I-A组的番茄巨芽病植原体(Tomato big bug,BB)、16Sr I-B组的西方翠菊黄化病植原体(Western aster yellow, SAY)和16SrI-C组中的三叶草变叶病植原体(Clover phyllody,CPh)的同源率达最高,分别为98.7%、99.1%和98.3%。进一步比较CWB-YN株系核糖体蛋白基因rps3基因编码的氨基酸序列同源性,结果与16S rI–B亚组的翠菊黄化病植原体(Aster yellows,AY)和长春花黄化病植原体(Periwinkle yellows,PY)的同源性最高,分别达98.1%和100%。CWB-GZh株系核糖体蛋白基因rps3基因编码的氨基酸序列同源率与16S rI–B亚组的AY和PY最高达98.1%和100%。基本确定了这两种植原体株系属于翠菊黄化组B亚组(16SrI-B,rp-B)。本研究同时还运用PCR-RFLP技术对上述两个植原体株系进行酶切图谱比较分类鉴定以及确定来源不同的苦楝丛枝病植株是否存在不同亚组的植原体株系复合侵染的现象,结果也表明这两个株系均属于翠菊黄化组B亚组,且采自不同省份的两个苦楝丛枝病植株没有植原体株系的复合侵染。更多还原

【Abstract】 Using universal primers (R16mF2/Rl and R16F2/R2) for 16S rRNA and primers (rpF1/rpR1) for ribosomal protein gene to detect phytoplasmas associated with of chinaberry tree witches’-broom from Yunnan and Guizhou Province by polymerase chain reaction. This indicated they were phytoplasma diseases and the phytoplasma strains were designed as CWB-YN and CWB-GZh, repectively.The amplified fragments of 16S rRNA gene and ribosomal protein gene of CWB-YN and CWB-GZh were cloned and sequenced,repectively. The results showed that the nucleotide sequences of 16S rRNA genes and ribosomal protein gene were comprised of 1248 base pairs and 1242 base pairs, respectively. Comparing the nucleotide sequences of 16S rRNA gene and ribosomal protein gene, we could find that these two strains have the highest homology of 99.4% and 99.8%, respectively. The nucleotide sequences of 16S rRNA gene for the CWB-YN strain shared higher homology (98.5%,98.9% and 98.0%) with phytoplasma strains in Tomato big bug (16SrI-A group, Western aster yellow (16SrI-B group) and Clover phyllody (16SrI-C group). But it is obviously under 97.0% with other phytoplasma groups. The CWB-GZh strain shared higher homology (98.7%,99.1% and 98.3%) with phytoplasma strains in Tomato big bug(16SrI-A group ),Western aster yellow (16SrI-B group) and Clover phyllody (16SrI-C group). But it is obviously under 97.0% with other groups. With further comparing the rps3 gene of ribosomal protein gene for the CWB-YN strain,the results show that these strains shared highest homology (98.1% and 100%)with Aster yellows and Periwinkle yellows (rp-B group).The rps3 gene of ribosomal protein gene for the CWB-GZh shared highest homology (98.1% and 100%) with phytoplasma strains in Aster yellows (16SrI-B group) and Periwinkle yellows (16SrI-B group). So the results made it clear that this phytoplasma strain is one of the members of Aster yellows phytoplasma group (16SrI-B group).So the results made it clear that these two phytoplasma strains are one of the members of Aster yellows phytoplasma group (16SrI-B, rp-B group).更多还原