| 摘要: |
| 【目的】分析陕北8个县(区)马铃薯X病毒外壳蛋白(CP)基因序列的一致性和变异性，明确病毒变异程度，为脱毒马铃薯的推广提供参考。【方法】以陕北8个县（区）种植2～3代疑似携带病毒的马铃薯叶片为材料，首先用Trizol法提取8个采样点马铃薯叶片总RNA，以已公布的马铃薯X病毒CP基因序列设计特异引物，通过RT-PCR扩增目的DNA片段，用琼脂糖凝胶电泳检测扩增产物；然后对CP基因进行克隆并测序，使用DNAstar软件分析陕北马铃薯X病毒CP基因序列的一致性，并与国内外其他地区12个马铃薯X病毒进行比较，采用邻接法构建系统进化树。【结果】从陕北8个县（区）马铃薯叶片中均扩增到与预期大小一致的长度为620 bp目的片段，可知这些马铃薯均感染了X病毒。不同CP基因序列之间存在微小变异，8个县(区)样品间CP基因的序列一致性在95.2%～99.4%，与国内外其他地区12个样品CP基因的序列一致性在92.9%～98.5%。系统进化树显示，将X病毒可分为4个类群，而陕北8县(区) 马铃薯X病毒归属于其中的2个类群。【结论】马铃薯X病毒在陕北地区普遍存在，RT-PCR方法可快速、准确地检测到马铃薯X病毒，X病毒CP基因存在一定程度的变异。 |
| 关键词: 马铃薯X病毒 外壳蛋白基因 RT-PCR 序列分析 |
| DOI： |
| 分类号: |
| 基金项目:陕西省教育厅项目(08JK508，08JK509) |
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| RT-PCR detection and sequence analysis of CP gene of potato virus X in northern Shaanxi |
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FENG Guang-hui,DU Hu-ping,LI Xia-long,et al
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| Abstract: |
| 【Objective】The identity and variation of CP gene sequence of potato virus X in 8 counties (districts) in northern Shaanxi were detected by RT-PCR to clarify the virus variation and provide a reference for the promotion of detoxification potato.【Method】Taking leaves of suspected poison potatoes at 2-3 generations as materials,the total RNAs were extracted by Trizol method at 8 sampling sites.Specific primers were designed based on published CP gene sequences of potato virus X and DNAs were amplified using RT-PCR method.The PCR products were examined by agarose gel electrophoresis.Then the target gene was cloned and sequenced,and the identity of sequence was analyzed by DNAstar software and compared with the CP gene identities of 12 X viruses at home and abroad.At last,phylogenetic tree was constructed using neighbor joining method.【Result】Expected fragments with the size of 620 bp were obtained from all 8 samples after amplification,indicating that all these potatoes were infected with potato virus X.There was minor difference between different CP genes sequence and identity of the tested sequences was 95.2%-99.4%.The identity of all samples at home and abroad was 92.9%-98.5%.The potato virus X could be divided into 4 groups based on CP gene phylogenetic trees,and the samples from 8 counties (districts) of northern Shaanxi belonged to two groups.【Conclusion】Potato virus X was widespread in northern Shaanxi. It can be rapidly and accurately detected by RT-PCR,and there existed a certain degree of variation in the CP gene. |
| Key words: potato virus X CP gene RT-PCR sequence analysis |
