摘 要 ：番木瓜环斑病毒(Papaya ring spot virus，PRSV)和番木瓜畸形花叶病毒（Papaya leaf-distortion mosaic virus，PLDMV）是热带、亚热带地区严重威胁番木瓜农业生产的主要病害。本研究对27份疑似番木瓜花叶病病叶样品进行分子鉴定，提取病叶总RNA，反转录获得对应的cDNA，根据PRSV病毒的CP、P1、Hc-Pro和NIb基因序列和PLDMV病毒的CP基因序列设计特异性引物进行PCR检测和测序分析。研究发现PRSV感染20例（74.1%），PLDMV感染3例（11.1%），PRSV和PLDMV交叉感染的样品1例（3.7%）。多样性分析结果表明，海南地区PRSV病毒存在3个株系，株系之间出现明显分化；海南地区PLDMV病毒与日本和中国台湾地区报道的PLDMV病毒株系有共同的起源。研究结果表明PRSV和PLDMV是海南地区番木瓜花叶病的主要病原，其中PRSV病毒3个株系之间P1基因同源性在95%以下，这可为后续研究构建抗PRSV和PLDMV的双价表达载体提供数据支持。
Abstract:Papaya ring spot virus(PRSV) and Papaya leaf-distortion mosaic virus(PLDMV) are dominant viruses causing papaya leaf mosaic disease in tropical and subtropical regions, threatening papaya planting industry. In this study, 27 suspected papaya leaf mosaic disease samples were collected and identified from Sanya, Ledong, Wanning and Qionghai in Hainan province. Total RNA from leaves was extracted and used for reverse transcription to obtain the corresponding cDNAs. Gene-specific primers were designed according to CP, P1, Hc-Pro and NIb gene nucleotide sequences from PRSV genome and CP gene nucleotide sequences from PLDMV genome. By PCR and sequencing, 20 PRSV-infected samples(74.1%), 3 PLDMV-infected samples(11.1%) and 1 PRSV-PLDMV cross-infected sample(3.7%) were identified. Phylogeny analysis showed that 3 PRSV varieties were existed in Hainan province with high strain differentiation, whereas, PLDMV varieties in Hainan province had a common origin with PLDMV varieties from Taiwan and Chian and Japan. The results showed that PRSV and PLDMV were dominant papaya mosaic viruses in Hainan, and the homology was below 95% during 3 PRSV varieties. This study would contribute to the subsequent construction of bivalent expression vector that could resist both PRSV and PLDMV viruses.