瓜类褪绿黄化病毒及其系统进化分析

【目的】检测新疆南疆7个县/市瓜类褪绿黄化病毒(Cucurbit chlorotic yellows virus, CCYV),进行系统发育分析,为新疆南疆CCYV预警和防控提供参考。【方法】于2019年,从中国新疆南疆7个县/市采集带有黄化特征的51份甜瓜叶片样品,RT-PCR进行CCYV的检测,进行特异性片段的克隆、测序和系统发育分析。【结果】中国新疆巴楚县、阿克苏市、莎车县、伽师县、疏勒县、疏附县均未检测到CCYV,而洛浦县的13份样本中,8份检出为CCYV阳性,检出率为61.53%,洛浦县CCYV特异性片段克隆测序获得了685 bp的核酸序列,与GenBank中的CCYV分离物外壳蛋白(Coat protein, CP)的一致性达到100%。所得序列与中国新疆(吐鲁番)、中国其他省、苏丹、日本、塞浦路斯、黎巴嫩的CP基因聚在I组(Group),沙特阿拉伯的分离物聚在Ⅱ组,伊朗的分离物聚在Ⅲ组。【结论】CCYV在中国新疆南疆洛浦县甜瓜产区发生,与中国新疆吐鲁番、中国其他省及周围国家的CCYV分离物亲缘关系很近,且群体遗传变异很小。

The Occurrence of Cucurbit chlorotic yellows virus in Lop County in Hotan and Its Phylogenetic Analysis

【Objective】 To detect Cucurbit chlorotic yellows virus(CCYV)in seven counties/city in Southern Xinjiang and analyze the phylogenetic relationship with a view to providing a reference for CCYV early warning and control in Southern Xinjiang. 【Methods】 In 2019, 51 samples of muskmelon leaves with yellowing symptoms were collected from 7 counties/city in southern Xinjiang and CCYV detection was carried out by RT-PCR for cloning, sequencing and phylogenetic analysis of specific fragments. 【Results】 CCYV was not detected in Bachu County, Aksu City, Shache County, Jiashi County, Shule County and Shufu County, while 8 of 13 samples in Lop County were detected with CCYV, and detection ratio was 61.53%. A 685 bp nucleic acid sequence of CCYV in Lop County was obtained by sequencing, and the consistency with the CCYV isolate shell protein (coat protein, cp) in the GenBank reached 100%. The phylogenetic tree based on CP gene sequence showed that the CP genes of Xinjiang (Turpan), other provinces of China, Sudan, Japan, Cyprus and Lebanon were clustered in group I, Saudi Arabia isolates were clustered in group II, Iran isolates were clustered in group III. 【Conclusion】 CCYV that first occurred in the main melon area of Lop County of southern Xinjiang has close genetic relationships with Turpan, Xinjiang,China, and surrounding countries whose population genetic variation is very low.