Department of Genetic Engineering, Dong-A University, Busan, Republic of Korea.
Phytopathology. 2010 Oct;100(10):1089-99. doi: 10.1094/PHYTO-01-10-0014.
Pierce's disease (PD), caused by Xylella fastidiosa, represents one of the most damaging diseases of cultivated grape. Management of PD in the vineyard often relies on the removal of infected individuals, which otherwise serve as a source of inoculum for nearby healthy vines. Effective implementation of such control measures requires early diagnosis, which is complicated by the fact that infected vines often harbor high titers of the pathogen in advance of visual symptom development. Here, we report a biomarker system that simultaneously monitors Xylella-induced plant transcripts as well as Xylella ribosomal (r)RNA. Plant biomarker genes were derived from a combination of in silico analysis of grape expressed sequence tags and validation by means of reverse-transcriptase polymerase chain reaction (RT-PCR). Four genes upregulated upon PD infection were individually multiplexed with an X. fastidiosa marker rRNA and scored using either real-time RT-PCR or gel-based conventional RT-PCR techniques. The system was sufficiently sensitive to detect both host gene transcript and pathogen rRNA in asymptomatic infected plants. Moreover, these plant biomarker genes were not induced by water deficit, which is a component of PD development. Such biomarker genes could have utility for disease control by aiding early detection and as a screening tool in breeding programs.
皮尔森氏病（PD）由韧皮部杆菌引起，是对栽培葡萄危害最大的疾病之一。葡萄园对 PD 的管理通常依赖于感染个体的清除，否则它们将成为附近健康葡萄藤的接种源。这种控制措施的有效实施需要早期诊断，而感染葡萄藤在出现明显症状之前通常会携带高浓度的病原体，这使得诊断变得复杂。在这里，我们报告了一个生物标志物系统，该系统可以同时监测 Xylella 诱导的植物转录物和 Xylella 核糖体（r）RNA。植物生物标志物基因源自对葡萄表达序列标签的计算机分析，并通过逆转录聚合酶链反应（RT-PCR）进行验证。在 PD 感染后上调的四个基因分别与 X. fastidiosa 标记 rRNA 进行多重扩增，并使用实时 RT-PCR 或基于凝胶的常规 RT-PCR 技术进行评分。该系统足够灵敏，可以检测无症状感染植物中的宿主基因转录物和病原体 rRNA。此外，这些植物生物标志物基因不会被水分亏缺诱导，而水分亏缺是 PD 发展的一个组成部分。这些生物标志物基因可以通过辅助早期检测和作为育种计划中的筛选工具，用于疾病控制。
