Chen Y K, Yang C C, Hsu H T
Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan.
Floral and Nursery Plants Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland, 20705.
Plant Dis. 2005 May;89(5):529. doi: 10.1094/PD-89-0529B.
Allamanda (Allamanda cathartica L., family Apocynaceae) is native to Brazil and is a popular perennial shrub or vine ornamental in Taiwan. Plants showing severe mosaic, rugosity, and leaf distortion symptoms on leaves are common in commercial nurseries and private gardens. Examination of crude sap prepared from symptomatic leaves using an electron microscope revealed the presence of spherical virus particles with a diameter of approximately 28 nm. The virus was mechanically transmitted to indicator plants and induced symptoms similar to those incited by Cucumber mosaic virus (CMV). The virus caused local lesions on inoculated leaves of Chenopodium quinoa and C. amaranticolor and systemic mosaic in Cucumis sativus, Lycopersicon esculentum, Nicotiana benthamiana, N. glutinosa, N. rustica, and N. tabacum. On N. tabacum, necrotic ringspots developed on inoculated leaves followed by systemic mosaic. Tests of leaf sap extracted from naturally infected allamanda and inoculated indicator plants using enzyme-linked immunosorbent assay were positive to rabbit antiserum prepared to CMV. Viral coat protein on transblots of sodium dodecyl sulfate-polyacrylamide gel electrophoresis reacted with CMV subgroup I specific monoclonal antibodies (2). With primers specific to the 3'-half of RNA 3 (1), amplicons of an expected size (1,115 bp) were obtained in reverse transcription-polymerase chain reaction (RT-PCR) using total RNA extracted from infected allamanda and N. benthamiana. The amplified fragment (EMBL Accession No. AJ871492) was cloned and sequenced. It encompasses the 3' part of the intergenic region of RNA 3 (158 nt), CP ORF (657 nt), and 3' NTR (300 nt) showing 91.8-98.9% and 71.4-72.8% identities to those of CMV in subgroups I and II, respectively. Results of MspI-digested restriction fragment length polymorphism patterns of the RT-PCR fragment and the nucleotide sequence analysis indicate that the CMV isolate from allamanda belongs to subgroup IB, which is predominant on the island. To our knowledge, CMV is the only reported virus that infects allamanda and was first detected in Brazil (3), and this is the first report of CMV infection in allamanda plants occurring in Taiwan. References: (1) Y. K. Chen et al. Arch. Virol. 146:1631, 2001. (2) H. T. Hsu et al. Phytopathology 90:615, 2000. (3) E. W. Kitajima. Acta. Hortic. 234:451, 1988.
黄蝉（黄蝉，夹竹桃科）原产于巴西，是台湾地区一种常见的多年生灌木或藤本观赏植物。在商业苗圃和私人花园中，叶片出现严重花叶、皱缩和叶畸形症状的植株很常见。用电子显微镜检查有症状叶片制备的粗汁液，发现存在直径约28纳米的球形病毒粒子。该病毒通过机械接种传播到指示植物上，并诱发与黄瓜花叶病毒（CMV）相似的症状。该病毒在接种的藜和苋色藜叶片上引起局部病斑，在黄瓜、番茄、本氏烟、黏毛烟草、黄花烟草和烟草上引起系统花叶。在烟草上，接种叶片上出现坏死环斑，随后出现系统花叶。用酶联免疫吸附测定法检测从自然感染的黄蝉和接种指示植物中提取的叶汁液，对用CMV制备的兔抗血清呈阳性反应。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳转印膜上的病毒外壳蛋白与CMV亚组I特异性单克隆抗体发生反应（2）。用RNA 3 3'-末端特异性引物（1），以从感染的黄蝉和本氏烟中提取的总RNA进行逆转录-聚合酶链反应（RT-PCR），获得预期大小（1115 bp）的扩增片段。扩增片段（EMBL登录号AJ871492）被克隆并测序。它包含RNA 3基因间隔区的3'部分（158 nt）、外壳蛋白开放阅读框（657 nt）和3'非翻译区（300 nt），与CMV亚组I和II的相应序列分别具有91.8 - 98.9%和71.4 - 72.8%的同源性。RT-PCR片段的MspI酶切限制性片段长度多态性模式结果和核苷酸序列分析表明，从黄蝉分离的CMV分离物属于亚组IB，该亚组在该岛占主导地位。据我们所知，CMV是唯一报道的感染黄蝉的病毒，最早在巴西被检测到（3），这是台湾地区黄蝉植株中CMV感染的首次报道。参考文献：（1）Y. K. Chen等人，《病毒学档案》146:1631，2001年。（2）H. T. Hsu等人，《植物病理学》90:615，2000年。（3）E. W. Kitajima，《园艺学报》234:451，1988年。
