Klap Chen, Luria Neta, Smith Elisheva, Bakelman Elena, Belausov Eduard, Laskar Orly, Lachman Oded, Gal-On Amit, Dombrovsky Aviv
Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, 68 HaMaccabim Road, P.O.B 15159 Rishon LeZion 7505101, Israel.
The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 761001, Israel.
Plants (Basel). 2020 May 14;9(5):623. doi: 10.3390/plants9050623.
During 2019, tomato fruits showing viral-like symptoms of marbled yellow spots were abundant in Israel. The new symptoms were distinctive from those typical of tomato brown rugose fruit virus (ToBRFV) infection but resembled symptoms of pepino mosaic virus (PepMV) infection. RT-PCR analysis and the serological tests (enzyme linked immunosorbent assay, western blot and in situ immunofluorescence) revealed and confirmed the presence of both the tobamovirus ToBRFV and the potexvirus PepMV in the symptomatic fruits. A mixture of rod-like and filamentous particles, characteristic of viruses belonging to tobamovirus and potexvirus genera, was visualized by transmission electron microscopy of the tomato fruit viral extract. Sanger sequencing of amplified PepMV-coat protein gene segments showed ~98% sequence identity to the Chilean (CH2)-strain. In a biological assay testing the contribution of traded infected tomatoes to the establishment of tomato plant disease, we applied direct and indirect inoculation modes using -resistant tomato plants. The results, assessed by disease symptom development along with serological and molecular analyses, showed that the ToBRFV and PepMV co-infected fruits were an effective inoculum source for disease spread only when fruits were damaged. Importantly, intact fruits did not spread the viral disease. These results added a new factor to disease epidemiology of these viruses.
2019年期间，以色列出现大量带有大理石花纹黄斑等类病毒症状的番茄果实。这些新症状与番茄褐色皱纹果病毒（ToBRFV）感染的典型症状不同，但与番木瓜花叶病毒（PepMV）感染的症状相似。逆转录聚合酶链反应（RT-PCR）分析和血清学检测（酶联免疫吸附测定、蛋白质免疫印迹和原位免疫荧光）揭示并证实了有症状果实中同时存在烟草花叶病毒属的ToBRFV和马铃薯X病毒属的PepMV。通过对番茄果实病毒提取物进行透射电子显微镜观察，发现了属于烟草花叶病毒属和马铃薯X病毒属病毒特征性的杆状和丝状粒子混合物。对扩增的PepMV外壳蛋白基因片段进行桑格测序，结果显示其与智利（CH2）株的序列同一性约为98%。在一项检测交易的受感染番茄对番茄植株病害发生影响的生物学试验中，我们使用抗性番茄植株采用了直接和间接接种方式。通过病害症状发展以及血清学和分子分析评估的结果表明，只有当果实受损时，ToBRFV和PepMV共同感染的果实才是病害传播的有效接种源。重要的是，完整的果实不会传播病毒病害。这些结果为这些病毒的病害流行病学增添了一个新因素。
