Faria J C, Souza-Dias J A C, Slack S A, Maxwell D P
Centro Nacional de Pesquisas de Arroz e Feijão (CNPAF), Caixa Postal 179, Goiânia, GO, 74001, Brazil.
Instituto Agronômico de Campinas, Caixa Postal 28, Campinas, SP 13001, Brazil.
Plant Dis. 1997 Apr;81(4):423. doi: 10.1094/PDIS.1997.81.4.423B.
The apical growth of about 20% of young tomato plants in observed fields near Campinas, State of São Paulo, Brazil, had yellow streaking of veins. Leaf symptoms developed into patches of yellow mosaic and the leaves became wavy. The whitefly Bemisia tabaci Genn. transmitted a pathogen from the infected tomato plants to healthy tomato and potato plants, reproducing the original symptoms in tomato. The apical leaves of infected potatoes showed yellow or green mottle that developed into leaf distortion with yellow blotches, symptoms indistinguishable from potato-deforming mosaic disease (2). DNA was extracted from these tomato and potato plants (1). Using DNA from the infected tomato plant, polymerase chain reaction (PCR) with the degenerate primer pair PAC1v1978/ PAV1c715 (1), which amplifies part of the rep gene (AC1 ORF), the common region (CR), and part of the cp gene (AV1 ORF), and with the primer pair PBC1v2039/PBV1c800, which amplifies part of BC1 ORF, CR, and part of BV1 ORF, gave virus-specific DNA fragments of the sizes expected from a whitefly-transmitted geminivirus. These were cloned and the complete nucleotide (sequences for DNA-A (pToYA, GenBank accession no. U79998) and DNA-B (pToYB, GenBank accession no. U80042) fragments obtained. Nucleotide identity between the CRs (184 nucleotides) was 90%, strongly indicating that those fragments correspond to a bipartite subgroup III geminivirus. PCR with the DNA from infected potato gave the expected size fragment for DNA-A. The partial sequence of the rep gene was 100% identical to the homologous sequence from the PCR fragment from the infected tomato. A search in the GenBank, EMBL, DDBJ, and PDB databases, using the BLAST program, found no identical geminivirus. The highest identity for the CR was 75% to tomato mottle geminivirus-Florida (ToMoV) and 74% to bean golden mosaic virus-Brazil. For the rep gene, the highest identity was 73% to tomato yellow leaf curl virus-Israel, an Old World geminivi-rus, followed by 71% to tomato golden mosaic virus-Brazil (TGMV) and ToMoV. For the cp gene, the highest identity was 86% to TGMV, followed by 83% to squash leaf curl geminivirus. Therefore, we propose the name tomato yellow vein streak geminivirus (ToYVSV) for this distinct virus (2). References: (1) M. R. Rojas et al. Plant Dis. 77:340, 1993. (2) J. A. C. Souza-Dias et al. Summa Phytopathol. 22:57, 1996.
在巴西圣保罗州坎皮纳斯附近的观察田中，约20%的番茄幼苗顶端生长出现叶脉黄化条纹。叶片症状发展为黄斑花叶，叶片变得卷曲。烟粉虱Bemisia tabaci Genn. 将病原体从受感染的番茄植株传播到健康的番茄和马铃薯植株上，在番茄中再现了最初的症状。受感染马铃薯的顶端叶片出现黄色或绿色斑驳，进而发展为叶片扭曲并伴有黄斑，这些症状与马铃薯变形花叶病难以区分(2)。从这些番茄和马铃薯植株中提取了DNA(1)。使用来自受感染番茄植株的DNA，用简并引物对PAC1v1978/PAV1c715(1)进行聚合酶链反应(PCR)，该引物对可扩增部分rep基因(AC1 ORF)、共同区域(CR)和部分cp基因(AV1 ORF)，并用引物对PBC1v2039/PBV1c800进行PCR，该引物对可扩增部分BC1 ORF、CR和部分BV1 ORF，得到了预期大小的病毒特异性DNA片段，这些片段来自粉虱传播的双生病毒。将这些片段进行克隆，获得了DNA-A(pToYA，GenBank登录号U79998)和DNA-B(pToYB，GenBank登录号U80042)片段的完整核苷酸序列。CRs(184个核苷酸)之间的核苷酸同一性为90%，强烈表明这些片段对应于双分体亚组III双生病毒。用来自受感染马铃薯的DNA进行PCR，得到了预期大小的DNA-A片段。rep基因的部分序列与来自受感染番茄的PCR片段的同源序列100%相同。使用BLAST程序在GenBank、EMBL、DDBJ和PDB数据库中搜索，未发现相同的双生病毒。CR的最高同一性为75%与番茄斑驳双生病毒-佛罗里达株(ToMoV)，74%与菜豆金色花叶病毒-巴西株。对于rep基因，最高同一性为73%与番茄黄化曲叶病毒-以色列株，一种旧大陆双生病毒，其次为71%与番茄金色花叶病毒-巴西株(TGMV)和ToMoV。对于cp基因，最高同一性为86%与TGMV，其次为83%与南瓜曲叶双生病毒。因此，我们为这种独特的病毒提议命名为番茄黄脉条纹双生病毒(ToYVSV)(2)。参考文献：(1)M.R.罗哈斯等人，《植物病害》77:330:340，1993年。(2)J.A.C.索萨-迪亚斯等人，《植物病理学综述》22:57，1996年。
