中国农业科学 ›› 2025, Vol. 58 ›› Issue (19): 3890-3904.doi: 10.3864/j.issn.0578-1752.2025.19.007

• 植物保护 • 上一篇    下一篇

ToLCNDV广东冬瓜分离物的分子特征及其遗传演化规律

郭孟泽1(), 张磊1, 孙平平1, 江彪2, 闫晋强2(), 李正男1()   

  1. 1 内蒙古农业大学园艺与植物保护学院,呼和浩特 010018
    2 广东省农业科学院蔬菜研究所/广东省蔬菜新技术研究重点实验室,广州 510640
  • 收稿日期:2025-07-09 接受日期:2025-07-28 出版日期:2025-10-01 发布日期:2025-10-10
  • 通信作者:
    闫晋强,E-mail:
    李正男,E-mail:
  • 联系方式: 郭孟泽,E-mail:guomengze0023@emails.imau.edu.cn。
  • 基金资助:
    内蒙古自治区自然科学基金(2023LHMS03020); 内蒙古自治区自然科学基金(2022QN03018); 内蒙古自治区高等学校青年科技英才项目(NJYT23079)

Molecular Characterization and Evolutionary Dynamics of Tomato Leaf Curl New Delhi Virus Isolate from Wax Gourd (Benincasa hispida) in Guangdong

GUO MengZe1(), ZHANG Lei1, SUN PingPing1, JIANG Biao2, YAN JinQiang2(), LI ZhengNan1()   

  1. 1 College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010018
    2 Vegetable Research Institute, Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of Advanced Vegetable Research, Guangzhou 510640
  • Received:2025-07-09 Accepted:2025-07-28 Published:2025-10-01 Online:2025-10-10

摘要:

【目的】新德里番茄曲叶病毒(tomato leaf curl New Delhi virus,ToLCNDV)是近年来危害我国瓜类蔬菜最严重的病毒性病原之一。目前,有关中国流行株的基因组序列报道有限,且国内尚未报道ToLCNDV在冬瓜(Benincasa hispida)上的发生。本研究旨在明确ToLCNDV在广东冬瓜中流行规律,分析ToLCNDV中国分离物的序列特异性、致病性、遗传多样性以及时空迁移特征,为ToLCNDV的防控提供理论依据。【方法】通过高通量测序、PCR扩增技术对79份冬瓜样品进行ToLCNDV的检测和全基因组序列扩增,并进行系统发育、序列一致性、遗传多样性、贝叶斯系统发育及谱系地理分析。此外,通过汁液摩擦接种技术对12种ToLCNDV潜在寄主进行致病性验证。【结果】高通量测序结果表明,所采集冬瓜样品中存在ToLCNDV。PCR检测发现79份疑似病毒样本中58份感染了ToLCNDV,检出率高达73.4%;ToLCNDV冬瓜分离物可通过汁液摩擦接种侵染西瓜(Citrullus lanatus)、丝瓜(Luffa aegyptiaca)、西葫芦(Cucurbita pepo)、菜豆(Phaseolus vulgaris)、黄瓜(Cucumis sativus)、瓠瓜(Lagenaria siceraria)、克利夫兰烟(Nicotiana clevelandii)以及本氏烟(N. benthamiana)8种植物;ToLCNDV冬瓜分离物23GD_BeHi1的DNA A片段核苷酸序列全长为2 739 bp,DNA B片段核苷酸序列全长为2 693 bp;序列一致性分析结果显示,ToLCNDV冬瓜分离物与国内已知的ToLCNDV分离物DNA A和DNA B完整序列一致性分别在98.7%—99.7%和98.7%—99.3%;系统发育分析显示,基于ToLCNDV中国分离物DNA A和DNA B序列所重建的系统发育树均被分为两个明显的分支,且本研究所获的分离物均在Clade I分支;ToLCNDV中国分离物之间不存在重组事件;遗传多样性分析结果显示,ToLCNDV中国分离物群体内部遗传多样性相对较低,群体大小保持稳定且未发现重组事件,但江苏和上海分离物之间存在显著遗传分化;贝叶斯系统发育分析结果显示,基于DNA A和DNA B数据集所构建的MCC树的根均为浙江分离物,推断ToLCNDV的出现时间分别为2020年4月25日和2020年11月30日;谱系地理分析结果显示,浙江是我国ToLCNDV的起源中心,在广东发生了种群扩张。【结论】获得了我国ToLCNDV冬瓜分离物的全基因组序列,其DNA A和DNA B片段核苷酸序列全长分别为2 739和2 693 bp。通过摩擦接种证明其亦可侵染西葫芦、西瓜、丝瓜、黄瓜、菜豆、克利夫兰烟、瓠瓜以及本氏烟,并引起卷曲、褪绿等症状。

关键词: 新德里番茄曲叶病毒, 冬瓜, 全基因组序列, 遗传多样性, 谱系地理分析

Abstract:

【Objective】Tomato leaf curl New Delhi virus (ToLCNDV) is one of the most severe viral pathogens affecting cucurbit crops in recent years. Reports on the genome sequences of ToLCNDV isolates from China remain limited. ToLCNDV infection in wax gourd (Benincasa hispida) has not been reported in China. The objective of this study is to investigate the occurrence patterns of ToLCNDV in B. hispida in Guangdong Province, analyze sequence characteristics, pathogenicity, genetic diversity, and spatiotemporal dynamics of ToLCNDV isolates from China, and to provide a theoretical basis for the prevention and control of ToLCNDV.【Method】The complete genome of ToLCNDV was amplified using high-throughput sequencing and PCR. PCR assays were performed to detect ToLCNDV in 79 B. hispida samples. The obtained full-length genome sequences were subjected to phylogenetic analysis, sequence identity assessment, genetic diversity evaluation, Bayesian phylogenetics, and phylogeographic analysis. Pathogenicity was tested on 12 potential host species using mechanical sap-inoculation.【Result】High-throughput sequencing revealed that ToLCNDV was present in the collected B. hispida samples. PCR assays confirmed ToLCNDV infection in 58 of 79 suspected virus samples, representing a detection rate of 73.4%. The B. hispida isolate of ToLCNDV was mechanically transmissible through sap-inoculation to eight plant species. These included Citrullus lanatus, Luffa aegyptiaca, Cucurbita pepo, Phaseolus vulgaris, Cucumis sativus, Lagenaria siceraria, Nicotiana clevelandii, and N. benthamiana. All sap-inoculated plants developed characteristic symptoms. The complete nucleotide sequences of the DNA A and B components of the B. hispida isolate 23GD_BeHi1 were 2 739 and 2 693 bp, respectively. Pairwise sequence comparison showed 98.7%-99.7% identity for DNA A and 98.7%-99.3% for DNA B compared to representative Chinese ToLCNDV isolates. Phylogenetic trees based on complete DNA A and DNA B sequences of Chinese ToLCNDV isolates revealed two distinct clades. All isolates obtained in this study clustered within Clade I. No recombination events were detected among these isolates. Genetic diversity analyses indicated that the Chinese ToLCNDV population exhibited relatively low genetic diversity. The adequate population size remained stable, and no evidence of recombination was observed. However, significant genetic differentiation was detected between isolates from Jiangsu and Shanghai. Bayesian maximum clade credibility (MCC) trees constructed from DNA A and DNA B datasets placed Zhejiang isolates at the basal position. The estimated emergence times were April 25, 2020, for DNA A and November 30, 2020, for DNA B. Phylogeographic reconstruction suggested that Zhejiang served as the origin center of ToLCNDV in China, and the population expansion occurred in Guangdong.【Conclusion】The complete genome sequence of ToLCNDV isolate from B. hispida in China was obtained. The DNA A and B components comprise 2 739 and 2 693 bp, respectively. Mechanical sap-inoculation demonstrates that this isolate can infect C. pepo, C. lanatus, L. aegyptiaca, C. sativus, P. vulgaris, N. clevelandii, L. siceraria, and N. benthamiana. Infected plants develop leaf curling, chlorosis, and other typical symptoms.

Key words: tomato leaf curl New Delhi virus (ToLCNDV), wax gourd (Benincasa hispida), complete genome sequence, genetic diversity, phylogeographic analysis