Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod 123, Oman.
Virus Res. 2013 Oct;177(1):87-97. doi: 10.1016/j.virusres.2013.07.018. Epub 2013 Jul 30.
Tomato and pepper are widely grown in Oman for local consumption. A countrywide survey was conducted during 2010-2011 to collect samples and assess the diversity of begomoviruses associated with leaf curl disease of tomato and pepper. A virus previously only identified on the Indian subcontinent, chili leaf curl virus (ChLCV), was found associated with tomato and pepper diseases in all vegetable grown areas of Oman. Some of the infected plant samples were also found to contain a betasatellite. A total of 19 potentially full-length begomovirus and eight betasatellite clones were sequenced. The begomovirus clones showed >96% nucleotide sequence identity, showing them to represent a single species. Comparisons to sequences available in the databases showed the highest levels of nucleotide sequence identity (88.0-91.1%) to isolates of the "Pakistan" strain of ChLCV (ChLCV-PK), indicating the virus from Oman to be a distinct strain, for which the name Oman strain (ChLCV-OM) is proposed. An analysis for recombination showed ChLCV-OM likely to have originated by recombination between ChLCV-PK (the major parent), pepper leaf curl Lahore virus and a third strain of ChLCV. The betasatellite sequences obtained were shown to have high levels of identity to isolates of tomato leaf curl betasatellite (ToLCB) previous shown to be present in Oman. For the disease in tomato Koch's postulates were satisfied by Agrobacterium-mediated inoculation of virus and betasatellites clones. This showed the symptoms induced by the virus in the presence of the betasatellite to be enhanced, although viral DNA levels were not affected. ChLCV-OM is the fourth begomovirus identified in tomato in Oman and the first in Capsicum. The significance of these findings is discussed.
番茄和辣椒在阿曼广泛种植，供当地消费。2010-2011 年期间进行了全国范围的调查，以收集样本并评估与番茄和辣椒卷叶病相关的伴生病毒的多样性。此前仅在印度次大陆发现的辣椒曲叶病毒（ChLCV）与阿曼所有蔬菜种植区的番茄和辣椒病害有关。一些感染植物样本还含有β卫星。共测序了 19 个潜在全长伴生病毒和 8 个β卫星克隆。伴生病毒克隆的核苷酸序列同一性>96%，表明它们代表单一物种。与数据库中可用序列的比较显示，与“巴基斯坦”株 ChLCV（ChLCV-PK）的核苷酸序列同一性最高（88.0-91.1%），表明来自阿曼的病毒是一个独特的株系，因此提议将其命名为阿曼株（ChLCV-OM）。重组分析表明，ChLCV-OM 可能是由 ChLCV-PK（主要亲本）、辣椒曲叶拉合尔病毒和第三种 ChLCV 重组产生的。获得的β卫星序列与先前在阿曼存在的番茄曲叶β卫星（ToLCB）的分离物具有高度的同一性。番茄病害的柯克氏假设通过病毒和β卫星克隆的农杆菌介导接种得到满足。这表明在β卫星存在的情况下，病毒诱导的症状得到增强，尽管病毒 DNA 水平没有受到影响。ChLCV-OM 是在阿曼番茄中发现的第四种伴生病毒，也是辣椒中的第一种。讨论了这些发现的意义。
