Department of Plant Pathology, Volcani Center-ARO, Bet-Dagan, 50250, Israel.
Mol Plant Pathol. 2007 Mar;8(2):139-50. doi: 10.1111/j.1364-3703.2007.00381.x.
SUMMARY Taxonomy: Zucchini yellow mosaic virus (ZYMV) is a member of genus Potyvirus, family Potyviridae. ZYMV is a positive-strand RNA virus. Physical properties: Virions are flexuous filaments of 680-730 nm in length and 11-13 nm in diameter, composed of about 2000 subunits of a single 31-kDa protein (calculated). The genome RNA size is 9.6 kb covalently linked to a viral-encoded protein (the VPg) at the 5' end, and with a 3' poly A tail. The 5' end of the sequence is AU-rich (69%). Viral proteins: The genome is expressed as a polyprotein cleaved by three viral proteases and processed into ten putative mature proteins. The structural coat protein is processed from the carboxyl terminus of the polyprotein and is highly immunogenic. Host and symptoms: Natural and experimental infection has been reported mainly in the Cucurbitaceae. Experimental local lesion hosts include Chenopodium amaranticolour, C. quinoa and Gomphrena globosa. Some ZYMV strains cause symptomless infection as in Ranunculus sardous, Nicotiana benthamiana and Sesamum indicum. ZYMV causes stunting and major foliar deformation with dark green blisters and mosaics in cucurbit hosts, eventually developing a filamentous leaf phenotype. In general, symptoms are severe on cucurbit hosts and cause dramatic reductions in yields due to severe fruit deformation. The virus is present in all the plant tissues at relatively high concentrations (c. 0.1 mg/mL of purified virus per 1 g fresh leaf tissue). The most suitable species for maintenance and purification is Cucurbita pepo.
ZYMV is efficiently transmitted by aphids in a non-persistent manner. The coat protein (CP) and the helper component-protease (HC-Pro) are required for aphid transmission, through the CP DAG motif and the HC-Pro KLSC and PTK motifs. Mechanical transmission is efficient both in the laboratory and naturally. Economic importance: ZYMV disease is a major constraint in the production of cucurbits world-wide. The virus can cause massive damage (to total loss) to cucurbit crops, and prevents the growth of some cucurbit crops in certain areas. Control of ZYMV requires the integration of conventional resistance and transgenic breeding along with cross-protection technologies.
摘要分类学：南瓜黄花叶病毒（ZYMV）是马铃薯 Y 病毒科马铃薯 Y 病毒属的成员。ZYMV 是一种正链 RNA 病毒。物理性质：病毒粒子是长约 680-730nm、直径 11-13nm 的柔韧丝状，由大约 2000 个单链 31kDa 蛋白亚基组成（计算所得）。基因组 RNA 大小为 9.6kb，在 5'端与病毒编码的蛋白（VPg）共价连接，并带有 3'端多聚 A 尾。序列的 5'端富含 AU（69%）。病毒蛋白：基因组作为多蛋白表达，由三种病毒蛋白酶切割，并加工成十个假定的成熟蛋白。结构外壳蛋白从多蛋白的羧基末端加工而来，具有高度免疫原性。宿主和症状：已在葫芦科中主要报道了自然和实验性感染。实验性局部病变宿主包括苋色藜、藜和桂竹香。一些 ZYMV 株系在山芥、烟草和芝麻中引起无症状感染。ZYMV 导致瓜类植物生长迟缓，叶片严重变形，出现深绿色水疱和花叶，最终表现出丝状叶片表型。一般来说，在瓜类植物中症状严重，由于果实严重变形，导致产量大幅下降。病毒存在于所有植物组织中，浓度相对较高（每 1g 新鲜叶片组织中约有 0.1mg/ml 的纯化病毒）。最适合用于维持和纯化的物种是南瓜。
ZYMV 通过蚜虫以非持久方式高效传播。外壳蛋白（CP）和辅助成分蛋白酶（HC-Pro）通过 CP DAG 基序和 HC-Pro KLSC 和 PTK 基序对蚜虫传播是必需的。在实验室和自然条件下，机械传播效率都很高。经济重要性：ZYMV 病是全世界瓜类生产的主要制约因素。该病毒可导致瓜类作物大量减产（甚至绝收），并阻止某些瓜类作物在某些地区生长。ZYMV 的防治需要常规抗性和转基因育种与交叉保护技术的整合。
