McNeil Christopher J, Araujo Karla, Godfrey Kristine, Slupsky Carolyn M
Department of Food Science & Technology, University of California-Davis, Davis, CA 95616.
Contained Research Facility, University of California-Davis, Davis, CA 95616.
Phytopathology. 2023 Feb;113(2):299-308. doi: 10.1094/PHYTO-05-22-0177-R. Epub 2023 Feb 27.
is the pathogen that causes citrus stubborn disease (CSD). Infection of citrus with has been shown to cause leaf mottling, reduce fruit yield, and stunt tree growth. Fruit from trees exhibiting symptoms of CSD are misshapen and discolored. The symptoms of CSD are easily confused with nutrient deficiencies or symptoms of citrus greening disease. In this study, young Washington navel oranges () were graft-inoculated with budwood originating from trees confirmed to be infected with . Leaf samples were collected monthly for 10 months for metabolomics and differential gene expression analyses. Significant differences in the concentration of metabolites and expressed genes were observed between control and infected trees throughout the experiment. Metabolites and genes associated with important defense and stress pathways, including jasmonic acid signaling, cell wall modification, amino acid biosynthesis, and the production of antioxidant and antimicrobial secondary metabolites, were impacted by throughout the study, and even prior to symptom development. This work fills a current gap in knowledge surrounding the pathogenicity of and provides an updated mechanistic explanation for the development of CSD symptoms in infected plants.
是引起柑橘顽固病（CSD）的病原体。已证明柑橘感染 会导致叶片斑驳、果实产量降低和树木生长受阻。表现出CSD症状的树木所结的果实形状畸形且变色。CSD的症状很容易与营养缺乏或柑橘黄龙病的症状相混淆。在本研究中，用源自经确认感染 的树木的接穗对幼年华盛顿脐橙（ ）进行嫁接接种。每月采集叶片样本，持续10个月，用于代谢组学和差异基因表达分析。在整个实验过程中，观察到对照树和感染树之间代谢物浓度和表达基因存在显著差异。在整个研究过程中，甚至在症状出现之前，与重要防御和应激途径相关的代谢物和基因，包括茉莉酸信号传导、细胞壁修饰、氨基酸生物合成以及抗氧化和抗菌次生代谢物的产生，都受到 的影响。这项工作填补了目前围绕 致病性的知识空白，并为受感染植物中CSD症状的发展提供了更新的机制解释。
