Liu Liming, Wang Yanhui, Geng Yanfei, Yu Bo, Yan Leiyan, Hao Fangmin, Wu Huijie, Wang Pingyong, Gu Qinsheng, Kang Baoshan
Henan Key Laboratory of Fruit and Cucurbit Biology, Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou 450009, China.
Zhengzhou Agricultural Science and Technology Research Institute, Zhengzhou 450005, China.
Int J Mol Sci. 2025 May 1;26(9):4289. doi: 10.3390/ijms26094289.
Squash leaf curl China virus (SLCCNV) belongs to the species in the genus and can infect some Cucurbitaceae crops except for watermelon (). In this study, watermelon plants showing symptoms typical to begomovirus infection in field were observed in Zhejiang Province of China, and SLCCNV presence was identified through PCR and next-generation sequencing (NGS). The pairwise sequence identity of the DNA-A genome shows that SLCCNV watermelon isolate belongs to the SLCCNV/CN strain and shares 96% nucleotide identity with the previously sequenced SLCCNV/CN. An infectious clone of SLCCNV watermelon isolate was constructed using the tandem repeat fragment method. Through agrobacterium-mediated inoculation, the clone could induce systemic infection with typical symptoms in watermelon, melon (), squash (), pumpkin (), wax gourd (), cucumber (), and . It was further demonstrated that the progeny virions derived from the cloned watermelon isolate could be transmitted by whitefly rather than the sap. To the best of our knowledge, this is the first report of a natural infection of SLCCNV on watermelon in China, and the first complete report on the molecular characteristics and pathogenicity of watermelon-infecting SLCCNV in the world.
南瓜曲叶中国病毒（SLCCNV）属于该属的物种，可感染除西瓜（）以外的一些葫芦科作物。在本研究中，在中国浙江省田间观察到表现出典型双生病毒感染症状的西瓜植株，并通过聚合酶链式反应（PCR）和二代测序（NGS）鉴定出SLCCNV的存在。DNA-A基因组的两两序列同一性表明，SLCCNV西瓜分离株属于SLCCNV/CN株系，与先前测序的SLCCNV/CN具有96%的核苷酸同一性。利用串联重复片段法构建了SLCCNV西瓜分离株的感染性克隆。通过农杆菌介导接种，该克隆可在西瓜、甜瓜（）、南瓜（）、西葫芦（）、冬瓜（）、黄瓜（）和 中诱导典型症状的系统感染。进一步证明，源自克隆西瓜分离株的子代病毒粒子可通过烟粉虱传播而非汁液传播。据我们所知，这是中国首次报道SLCCNV自然感染西瓜，也是世界上首次关于感染西瓜的SLCCNV分子特征和致病性的完整报道。
