Abstract：Seed Zucchini (Cucurbita pepo), a major economic crop in Xinjiang, suffers severe yield and quality losses due to viral infections, and identifying its pathogens is essential for further control measures. In this study, leaf samples displaying mosaic symptoms were collected from Seed Zucchini in Shihezi, Xinjiang. Under an electron microscope, flexuous Potyvirus particles measuring approximately 750 × 11 nm were observed. The double-stranded RNA (dsRNA) of the virus was extracted, RT-PCR was performed on the virus with random primers and diffuse bands XHL2-1, XHL2-2, and XHL56 were obtained. BLAST searches in the NCBI database revealed that XHL2-1 and XHL56 had sequence similarities of 92.22%~98.69% and 96.21%~99.64%, respectively, with the corresponding regions of Zucchini yellow mosaic virus (ZYMV); XHL2-2 showed a sequence similarity of 89.38%~98.45% with the corresponding region of Watermelon mosaic virus (WMV). These findings indicated that the mosaic disease in Seed Zucchini might be caused by infections of both ZYMV and WMV. To further investigate, specific primers for ZYMV and WMV were designed and synthesized. RT-PCR was conducted on 15 samples, and ZYMV-specific amplification fragments from samples SH2, SH12, and SH13 were sequenced. The sequence similarity among these fragments was over 99.29%, with a similarity of 96.09%~99.56% to ZYMV sequences recorded in GenBank. The WMV-specific amplification fragments from samples SH1, SH9, and SH11 had sequence similarities exceeding 94.30% among themselves, and 94.74%~100% similarity with WMV sequences in GenBank. These results further confirmed that the mosaic disease in Seed Zucchini in Xinjiang was caused by co-infection of ZYMV and WMV. Phylogenetic analysis revealed that the ZYMV infecting Seed Zucchini in Xinjiang clusters with isolates from Eastern Europe and India, while the WMV was closely related to isolates from China, France, and other regions. This study identifies the primary pathogens of mosaic virus disease in Xinjiang's Seed Zucchini as a co-infection by ZYMV and WMV, providing a theoretical basis for further control measures against the disease.
[1] 陈虹. 2004. 黄瓜花叶病毒dsRNA的研究[D]. 硕士学位论文, 浙江大学, 导师: 陈声明, pp. 20-22. (Chen H.2004. Studies on dsRNA of cucumber mosaic virus[D]. Thesis for M.S., Zhejiang University, Supervisor: Chen S M, pp. 20-22.) [2] 菅彩媛, 苏文斌, 任霄云, 等. 2019. 籽用西葫芦新品种《金地3号》的选育及配套栽培技术[J]. 北方园艺, 19: 173-176. (Guan C Y, Su W B, Ren X Y, et al.2019. Breeding and cultivation technology of a new Zucchini 'Jindi No.3'[J]. Northern Horticulture, 19: 173-176.) [3] 韩盛, 韩成贵, 麦麦提玉山江, 等. 2016. 新疆吐鲁番地区三种甜瓜病毒病的发生与分子鉴定[J]. 新疆农业科学, 53(10): 1829-1842. (Han S, Han C G, Maimaiti Y S J, et al.2016. Occurrence and molecular identification of three kinds of melon virus diseases in turpan area, Xinjiang[J]. Xinjiang Agricultural Sciences, 53(10): 1829-1842.) [4] 刘升学, 向本春, 蔡瑜, 等. 2003. 甜菜坏死黄脉病毒不同分离物外壳蛋白的研究[J]. 石河子大学学报(自然科学版), 2: 91-94. (Liu S X, Xiang B C, Cai Yet al.2003. Studies on differentiation of coat protein of bnyvv isolates from Xinjiang[J]. Journal of Shihezi University (Natural Science), 2: 91-94.) [5] 彭斌. 2019. 中国葫芦科作物病毒的分布、多样性及进化研究[D]. 博士学位论文, 华中农业大学, 导师: 古勤生, pp. 3-4. ( Peng B.2019. Distribution, diversity and evolution of cucurbit viruses in China[D]. Thesis for Ph.D., Huazhong Agricultural University, Supervisor: Gu Q S, pp. 3-4.) [6] 任琛荣, 郝小军, 都业娟, 等. 2016. 新疆石河子及新湖籽用西葫芦病毒病分子检测[J]. 北方园艺, 1: 102-106. (Ren C R, Hao X J, Du Y J, et al.2016. Molecular detection of seed Zucchini virus diseases in Shihezi and Xinhu region in Xinjiang[J]. Northern Horticulture, 1: 102-106.) [7] 陶源, 吴兴泉. 2017. 植物病毒检测方法的研究进展[J]. 分子植物育种, 15(7): 2901-2906. (Tao Y, Wu X Q.2017. Research progress on methods for the detection of plant virus[J]. Molecular Plant Breeding, 15(7): 2901-2906.) [8] 田佳星, 张国裕, 邱艳红, 等. 2021. 西葫芦病毒病的研究进展[J]. 中国蔬菜, 5: 20-27. (Tian J X, Zhang G Y, Qiu Y H, et al.2021. Research progress on Cucurbita pepo L. virus disease[J]. China Vegetables, 5: 20-27.) [9] 王双超. 2013. 禾谷镰刀菌低毒病毒FgHV1的序列分析及生物学功能研究[D]. 硕士学位论文, 中国农业科学院, 导师: 邱德文, pp. 17-18. (Wang S C.2013. Sequence analysis and biological characteristics of Hypovirus FgHV1 from Fusarium graminearum[D]. Thesis for M.S., Chinese Academy of Agricultural Sciences, Supervisor: Qiu D W, pp. 17-18.) [10] 王志江, 杨海燕, 向本春, 等. 2015. 小西葫芦黄花叶病毒石河子分离物的分子变异[J]. 石河子大学学报(自然科学版), 33(6): 677-682. (Wang Z J, Yang H Y, Xiang B C, et al.2015. Molecular variability analysis of zucchini yellow mosaic virus isolates from Shihezi[J]. Shihezi University (Natural Science), 33(6): 677-682) [11] 岳建英, 韦学锋, 郑红丽, 等. 2021. 内蒙古籽用西葫芦病毒病病原鉴定[J]. 西北农林科技大学学报(自然科学版), 49(2): 61-67. (Yue J Y, Wei X F, Zheng H L, et al.2021. Identification of viral pathogen of zucchini in Inner Mongolia[J]. Journal of Northwest Agriculture & Forestry University (Natural Science Edition.), 49(2): 61-67.) [12] 张晓婷, 吴祖建, 林奇英, 等. 2005. 双链RNA技术与植物病毒研究[J]. 云南农业大学学报, 4: 455-458. (Zhang X T, Wu Z J, Lin Q Y, et al.2005. dsRNA isolation method and research of plant virology[J]. Journal of Yunnan Agriculture University, 4: 455-458.) [13] Anderson C W.1954. Two Watermelon mosaic virus strains from central Florida[J]. Phytopathology, 44(4): 198-202. [14] Chala V H, Harrison C W, Halliwell R S.1987. Identification of two distinct strains of watermelon mosaic virus 2 affecting cucurbits in Texas[J]. Plant Disease, 71(8): 750-752. [15] Coutts B A, Kehoe M A, Webster C G, et al.2011. Zucchini yellow mosaic virus: Biological properties, detection procedures and comparison of coat protein gene sequences[J]. Archives of Virology, 156(12): 2119-2131. [16] Desbiez C, Lecoq H.1997. Zucchini yellow mosaic virus[J]. Plant Pathology, 46: 809-829. [17] Sharifi M, Massumi H, Heydarnejad J, et al.2008. Analysis of the biological and molecular variability of Watermelon mosaic virus isolates from Iran[J]. Virus Genes. 37(3): 304-313.
