柳树黄化病植原体的分子分类

Molecular Classification of a Phytoplasma Associated with Willow Yellow Disease

摘要:

摘要：【目的】柳树黄化病是一种重要的植原体病害，本研究旨在明确柳树黄化病植原体（Willow Yellow phytoplasma,WY）的分类地位，为进一步开展致病性和防治研究奠定基础。【方法】采用植原体特异引物通过PCR 方法从患病植株DNA中扩增植原体16S rDNA基因和核糖体蛋白基因（ribosomal proteins gene ,rp）,对所得的序列进行分析，构建同源进化树，并用限制性片段长度多态性(RFLP)对巢式PCR产物进行分析。【结果】首次从柳树黄化病植原体中分离出了16S rDNA基因和rp基因，大小分别为1246 bp和1212 bp。 通过对植原体16S rDNA和rp基因的核苷酸同源性比较和RFLP分析,发现该分离物与16SrI组的核苷酸同源性均在99%以上,与16SrI -C 亚组中的小麦蓝矮病植原体同源性高达99.8%（16Sr DNA）和99.6 % （rp）,且RFLP分析与16SrI-C亚组的植原体有相同的酶切条带。【结论】柳树黄化植原体应划分于16SrI-C亚组。

Abstract:

Abstract：【Objective】Willow Yellow is a plant disease caused by phytoplasma. We identified the taxonomic status of Willow Yellow phytoplasma(WY). 【Methods】We used specific conservative primers amplified 16S rDNA and ribosomal proteins gene(rp)gene. Obtained sequences were then analyzed and homology trees were constructed. The nested - PCR products were also analyzed by restriction fragment length polymorphism (RFLP). 【Results】We obtained 16S rDNA of 1246 bp and rp gene of 1212 bp, and sequence analysis showed a high identity with members of the 16SrI-C group phytoplasmas, all above 99. 0%, and had the highest identity with Wheat Blue Dwarf phytoplasmas, 99.8 % (16S rDNA) and 99.6 % (rp) respectively, RFLP pattern are also the same as 16SrI-C phytoplsama.【Conclusion】Willow yellow phytoplasma is a member of 16SrI-C.