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黄瓜(Cucumis sativus)是世界范围内广泛分布的蔬菜,也是重庆主要经济作物之一。然而2013年以来,在重庆主要黄瓜种植区保护地及露地栽培的黄瓜上陆续发现病毒病症状植株。为明确采自重庆的5份表现植株矮化、叶片皱缩并有花叶、叶片扭曲的黄瓜病毒病的病原,利用11种常见蔬菜病毒特异引物,对样品进行了RT-PCR检测。检测结果表明,从黄瓜样品中扩增到了黄瓜花叶病毒(Cucumber mosaic virus,CMV)、南瓜花叶病毒(Squash mosaic virus,Sq MV)、芜菁花叶病毒(Turnip mosaic virus,Tu MV)、西瓜花叶病毒(Watermelon mosaic virus,WMV)和小西葫芦黄花叶病毒(Zucchini yellow mosaic virus,ZYMV)5种病毒,且均为4种及以上病毒的复合侵染。通过PCR、克隆和测序等技术获得WMV和ZYMV外壳蛋白(coat protein,CP)核苷酸序列,对序列进行了系统进化分析。结果表明,WMV重庆分离物WMV-H3与已报道的WMV各分离物CP核苷酸相似性在92.3%~96.9%,并与新疆哈密瓜(Cucumis melo var.saccharinus)上WMV-T-2-9相似性最高,为96.9%;ZYMV重庆分离物ZYMV-H3与安徽合肥分离物ZYMV-Hefei核苷酸相似性最高,为97.7%,与国内外已报道的ZYMV各分离物CP核苷酸相似性在93.0%~97.7%。系统进化树分析表明,44个WMV分离物被划分为5个基因型,WMV-H3属于基因型Ⅲ,WMV遗传变异与地理来源及寄主均存在一定的相关性,且与地域的相关性更强;80个ZYMV分离物被划分为6个基因型,ZYMV-H3属于基因型Ⅲ,ZYMV分离物分布具有一定地域分化。本研究首次研究了Sq MV、WMV和ZYMV在重庆地区黄瓜上的侵染危害,明确了重庆地区黄瓜上的病毒种类及进化起源,为进一步研究黄瓜病毒病分布及有效防控提供了理论依据。
Cucumbers (Cucumis sativus) are widely distributed in the world of vegetables, but also one of Chongqing’s major cash crops. However, since 2013, symptoms of virus disease have been found on the cucumbers in cucumbers and open-field cucumbers in major cucumber-growing areas in Chongqing. In order to clarify the pathogen of cucumber virus disease in dwarf, dwarfed leaves with folds and leaves distorted in Chongqing, 11 samples of common vegetables were identified by RT-PCR. The results showed that Cucumber mosaic virus (CMV), Squash mosaic virus (Sq MV), Turnip mosaic virus (Tu MV) were amplified from cucumber samples, Five viruses of Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV), and all of them were combined infection of four or more viruses. The nucleotide sequences of coat protein (CP) of WMV and ZYMV were obtained by PCR, cloning and sequencing, and the phylogenetic analysis of the sequences was carried out. The results showed that the nucleotide similarity of the WMV Chongqing isolate WMV-H3 to the reported WMV isolates was 92.3% -96.9%, and was similar to that of the WMV-T-2-9 strain on the Xinjiang melon (Cucumis melo var.saccharinus) The highest similarity was 96.9%. The ZYMV-H3 isolate of ZYMV Chongqing isolate had the highest similarity with ZYMV-Hefei nucleotide of Hefei isolate (97.7%), which was in good agreement with the reported nucleotide similarity of ZYMV isolates at home and abroad At 93.0% ~ 97.7%. Phylogenetic tree analysis showed that 44 WMV isolates were divided into five genotypes and WMV-H3 belonged to genotype Ⅲ. The genetic variation of WMV was related to both geographical origin and host, and was more related to the region ; 80 ZYMV isolates were divided into 6 genotypes, ZYMV-H3 genotype Ⅲ, ZYMV isolates with a certain geographical differentiation. This study for the first time studied the infectivity of Sq MV, WMV and ZYMV on cucumber in Chongqing, clarified the virus species and evolutionary origin in cucumber in Chongqing, and provided a theoretical basis for further study on the distribution and effective prevention and control of cucumber virus disease.