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【目的】明确云南省番木瓜环斑病毒(Papaya ringspot virus,PRSV)发生情况,并对其进行遗传多样性分析。【方法】利用RT-PCR技术,于2011-2012年对采自云南省昆明市、楚雄州、保山市、德宏州、西双版纳州、临沧市、玉溪市、红河州、文山州等地的24个番木瓜、南瓜和罗汉果疑似病样进行扩增、测序,对样品中获得的940 bp PRSV部分cp基因及3′端非编码区的序列应用分子生物学软件MEGA 5进行系统发育分析。【结果】从17个样品中检测到了PRSV,检出率为70.8%,表明该病毒在云南的发生较为普遍。云南PRSV不同分离物间的核苷酸序列变异较大,与其他已报道的PRSV分离物之间的基因组3′端核苷酸序列一致性为81.7%-100%。基于PRSV的CP部分氨基酸序列及基因组3′端核苷酸的系统进化分析结果表明,来自亚洲、北美洲、南美洲和大洋洲的PRSV分离物可以分为2个组,其中第Ⅰ组均为来自中国的分离物,包括了大部分的PRSV云南分离物,第Ⅰ组内分离物间的差异较第Ⅱ组大;第Ⅱ组的分离物来源较为复杂,亚洲、北美洲、南美洲和大洋洲均有分布。基于PRSV CP部分氨基酸序列构建的系统进化树中,各分离物之间没有明显的地理和寄主相关性,而基于PRSV基因组3′端核苷酸序列构建的系统进化树中,除中国大陆分离物和印度分离物外,其他地区的PRSV在进化上与其地理来源有明显的相关性。【结论】PRSV在云南的昆明市、楚雄州、保山市、德宏州、西双版纳州、临沧市、玉溪市、红河州和文山州等地都有不同程度发生,且为害寄主植物涉及番木瓜、南瓜及罗汉果,PRSV侵染罗汉果为云南首次发现。云南PRSV分离物的分子变异很大,但是关于PRSV的分子变异是否与其地理分布及症状表现有关,以及P型和W型的分子区分特征还有待进一步研究。
【Objective】 The objective of this study was to determine the occurrence of Papaya ringspot virus (PRSV) in Yunnan Province and analyze its genetic diversity. 【Methods】 RT-PCR was used to analyze the phenotypic changes between the two populations in Kunming City, Chuxiong Prefecture, Baoshan City, Dehong Prefecture, Xishuangbanna Prefecture, Lincang City, Yuxi City, Honghe Prefecture and Wenshan Prefecture in Yunnan Province from 2011 to 2012 24 papaya, pumpkin and mangosteen were amplified and sequenced. Phylogenetic analysis of the 940 bp PRSV partial cp gene and 3 ’noncoding region was carried out by using the molecular biology software MEGA 5. 【Result】 The results showed that PRSV was detected in 17 samples with a detection rate of 70.8%, indicating that the virus is prevalent in Yunnan. The variation of nucleotide sequence between different PRSV isolates in Yunnan Province was large, and the nucleotide sequence identity with the other 3 reported PRSV isolates was 81.7% -100%. Phylogenetic analysis based on the partial amino acid sequence of CP and the 3 ’nucleotide of the genome of PRSV showed that PRSV isolates from Asia, North America, South America and Oceania can be divided into two groups, China isolates, including most of the PRSV Yunnan isolates, the differences between the first group of isolates larger than the second group; the source of the second group of isolates more complicated, Asia, North America, South America and Oceania are There is distribution. Phylogenetic tree based on the partial amino acid sequence of PRSV CP showed no significant geographical and host-related relationship among the isolates. However, based on the phylogenetic tree constructed from the 3 ’nucleotide sequence of PRSV genome, And Indian isolates, PRSV in other regions is evidently related to its geographical origin. 【Conclusion】 PRSV occurred in different degrees in Kunming, Chuxiong, Baoshan, Dehong, Xishuangbanna, Lincang, Yuxi, Honghe and Wenshan prefectures in Yunnan Province, and the host plants were damaged by papaya , Pumpkin and Luo Han Guo, PRSV infection Luo Han Guo was first discovered in Yunnan. The molecular variation of PRSV isolates in Yunnan is very large. However, whether the molecular variation of PRSV is related to its geographical distribution and symptoms, and the molecular differentiation characteristics of P type and W type remains to be further studied.