Zeng R, Dai F M, Chen W J, Lu J P
Institute of Plant Protection, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences, 2901 Beidi Road, Shanghai 201106, P.R. China.
Plant Dis. 2011 Mar;95(3):354. doi: 10.1094/PDIS-08-10-0613.
In October 2007, symptoms of chlorosis on the upper leaves and a bright yellow color on the lower leaves were observed sporadically on hami melon (Cucumis melo cv. Xuelihong) in a high tunnel in Nanhui of Shanghai, China. Disease progresses from initial mottling of leaves into leaves that are completely yellow with the veins remaining green. The oldest leaves develop symptoms first, so these leaves have a pronounced even yellow color. In October 2009, these symptoms were found in all melons produced in the suburbs of Shanghai. These symptoms were similar to those caused by Cucurbit yellow stunting disorder virus (CYSDV) and Cucurbit chlorotic yellows virus (CCYV) (1-3). Twelve samples from symptomatic melons were collected in the Jiading, Nanhui, Fengxian, and Chongming districts of Shanghai for virus diagnosis. Large populations of whiteflies were observed in association with the diseased cucurbit crops. Total RNA was extracted with Trizol reagents (Invitrogen, Carlsbad, CA). We used random primers (9-mer) for reverse transcription-PCR. Extracts were for CYSDV using specific primers CYSDV-CP-F (5'-ATGGCGAGTTCGAGTGAGAA-3') and CYSDV-CP-R (5'-TCAATTACCACAGCCACCTG-3') to amplify a 756-bp fragment of coat protein gene and CCYV using specific primers CCYV-HSP-F1 (5'-TGCGTATGTCAATGGTGTTATG-3') and CCYV-HSP-R1 (5'-ATCCTTCGCAGTGAAAAACC-3') to amplify a 462-bp fragment of the HSP gene (1). CYSDV was not found in all samples. The expected 462-bp target fragment of CCYV was obtained in all samples but not from any of the healthy controls. All the 462-bp PCR products were cloned to pGEM-T vector (Promega, Madison, WI) and sequenced. All sequences obtained were homologous. A comparison of the submitted sequence (GenBank Accession No. HQ148667) with those in GenBank showed that the sequence had 100% nucleotide identity to the Hsp70h sequences of (CCYV) isolates from Japan (Accession Nos. AB523789 and AB457591) (1,4), Taiwan (Accession No. HM120250) (2), and mainland of China (Accession Nos. GU721105, GU721108, and GU721110). CCYV is a new member of the genus Crinivirus, first discovered in Japan in 2004 (4) and reported in Taiwan in 2009 (2). To our knowledge, this is the first report of CCYV on melon in China. References: (1) Y. Gyoutoku et al. Jpn. J. Phytopathol. 75:109, 2009. (2) L.-H. Huang et al. Plant Dis. 94:1168, 2010. (3) L. Z. Liu et al. Plant Dis.94:485, 2010. (4) M. Okuda et al. Phytopathology 100:560, 2010.
2007年10月，在中国上海南汇的一个连栋大棚内，偶见哈密瓜（品种：雪里红）上部叶片出现褪绿症状，下部叶片呈亮黄色。病害从叶片最初的斑驳发展为叶片完全变黄但叶脉仍为绿色。最老的叶片最先出现症状，所以这些叶片呈现出明显均匀的黄色。2009年10月，在上海郊区生产的所有甜瓜中均发现了这些症状。这些症状与由葫芦科黄化矮缩病毒（CYSDV）和葫芦科褪绿黄化病毒（CCYV）引起的症状相似（1 - 3）。从上海嘉定、南汇、奉贤和崇明地区有症状的甜瓜上采集了12个样本用于病毒诊断。在患病的葫芦科作物上观察到大量烟粉虱。用Trizol试剂（Invitrogen，卡尔斯巴德，加利福尼亚州）提取总RNA。我们使用随机引物（9聚体）进行逆转录 - PCR。提取物用于检测CYSDV，使用特异性引物CYSDV - CP - F（5'-ATGGCGAGTTCGAGTGAGAA-3'）和CYSDV - CP - R（5'-TCAATTACCACAGCCACCTG-3'）扩增衣壳蛋白基因的756 bp片段；检测CCYV，使用特异性引物CCYV - HSP - F1（5'-TGCGTATGTCAATGGTGTTATG-3'）和CCYV - HSP - R1（5'-ATCCTTCGCAGTGAAAAACC-3'）扩增HSP基因的462 bp片段（1）。所有样本中均未检测到CYSDV。所有样本中均获得了预期的462 bp的CCYV目标片段，但健康对照样本中均未获得。所有462 bp的PCR产物均克隆到pGEM - T载体（Promega，麦迪逊，威斯康星州）并进行测序。获得的所有序列均具有同源性。将提交的序列（GenBank登录号：HQ148667）与GenBank中的序列进行比较，结果表明该序列与来自日本（登录号：AB523789和AB457591）（1,4）、台湾（登录号：HM120250）（2）和中国大陆（登录号：GU721105、GU721108和GU721110）的CCYV分离株的Hsp70h序列具有100%的核苷酸同一性。CCYV是毛形病毒属的一个新成员，于2004年在日本首次发现（4），2009年在台湾报道（2）。据我们所知，这是CCYV在中国甜瓜上的首次报道。参考文献：（1）Y. Gyoutoku等人，《日本植物病理学杂志》75:109，2009年。（2）L.-H. Huang等人，《植物病害》94:1168，2010年。（3）L. Z. Liu等人，《植物病害》94:485，2010年。（4）M. Okuda等人，《植物病理学》100:560，2010年。
