Agricultural University of Athens, School of Agricultural Production, Infrastructure and Environment, Department of Crop Science, Plant Pathology Laboratory, Iera Odos 75, Votanikos, 11855 Athens, Greece.
Plant Dis. 2018 Nov;102(11):2268-2276. doi: 10.1094/PDIS-08-17-1259-RE. Epub 2018 Sep 6.
Worldwide, Cucumber mosaic virus (CMV) is the causal agent of many economically important diseases. Based on immunological or molecular analysis, three distinct subgroups of CMV isolates can be identified (IA, IB, and II). In addition, some CMV isolates are associated with satellite RNAs (satRNAs), a type of noncoding transcript that may alter the symptoms of CMV infections. This study presents an analysis of CMV isolates occurring in legumes in Greece in respect to their genetic diversity, and the presence and diversity of their satRNA. Phylogenetic analysis of the CMV coat protein sequence of 18 legume and 5 tomato CMV isolates collected throughout Greece classified them within subgroups IA and IB, with a limited genetic diversity. The CMV satRNAs found in nine field legumes exhibiting mild symptoms and in one tomato with a necrotic syndrome contained a functional necrogenic motif; therefore, they were grouped within the necrogenic group of CMV-satRNAs. The necrotic phenotype was expressed in all legume CMV isolates containing necrogenic satRNAs when mechanically inoculated onto tomato plants. To our knowledge, this is the first observation that legumes host necrogenic CMV-satRNAs. The possible role of legumes in the epidemiology of CMV and necrogenic satRNA complex is discussed.
在全球范围内，黄瓜花叶病毒（CMV）是许多具有重要经济意义的疾病的病原体。根据免疫学或分子分析，可以将 CMV 分离株分为三个不同的亚组（IA、IB 和 II）。此外，一些 CMV 分离株与卫星 RNA（satRNA）有关，卫星 RNA 是一种非编码转录本，可能改变 CMV 感染的症状。本研究对在希腊豆类作物中发生的 CMV 分离株进行了分析，以了解它们的遗传多样性，以及它们的 satRNA 的存在和多样性。对在希腊各地收集的 18 种豆类和 5 种番茄 CMV 分离株的 CMV 外壳蛋白序列进行的系统发育分析将它们归类为 IA 和 IB 亚组，遗传多样性有限。在表现轻度症状的 9 种田间豆类作物和 1 种表现坏死症状的番茄中发现的 CMV satRNA 含有功能的致坏死基序；因此，它们被归类为 CMV-satRNA 的致坏死组。当将含有致坏死 satRNA 的所有豆类 CMV 分离株机械接种到番茄植株上时，均表现出坏死表型。据我们所知，这是首次观察到豆类作物携带致坏死 CMV-satRNA。讨论了豆类在 CMV 和致坏死 satRNA 复合体的流行病学中的可能作用。
