Zhu Xiaohan, Gao Peng, Zhao Shuang, Luo Xian, Li Liang, Peng Gary
Saskatoon Research and Development Center, Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK S7N 0X2, Canada.
The Metabolomics Innovation Centre and Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
Int J Mol Sci. 2025 Jun 12;26(12):5627. doi: 10.3390/ijms26125627.
Blackleg disease poses a major threat to global canola production. The resistance gene , corresponding to the avirulence gene in the pathogen , has been widely used to mitigate the impact of the disease. To investigate the biochemical basis of -mediated resistance against blackleg, we conducted an LC-MS-based analysis of a susceptible Topas double haploid (DH) line and its isogenic -carrying resistant counterpart for metabolomic profiles during the infection process. Samples were labeled with C- and C for LC-MS analyses to enhance both chemical and physical properties of metabolites for improved quantification and detection sensitivity. Resistant plants showed early and sustained accumulation of several defense metabolites, notably pipecolic acid (PA, up to 326-fold), salicylic acid (SA), and gentisic acid (GA) in -inoculated Topas- plants compared to mock-inoculated Topas- controls (adjusted < 0.05), indicating activation of lysine degradation and hormonal defense pathways. Elevated glucosinolates (GLS), γ-aminobutyric acid (GABA), and melatonin precursors may further contribute to antimicrobial defense and cell-wall reinforcement. In contrast, flavonoid and phenylpropanoid pathways were down-regulated, suggesting metabolic reallocation during resistance. Exogenous application of PA, SA, GA, ferulic acid, and piperonylic acid (a known inhibitor of the phenylpropanoid pathway in plants) significantly reduced infection in susceptible canola varieties, validating their defense roles against blackleg. These results offer new insights into -mediated resistance and support metabolic targets for breeding durable blackleg resistance in canola.
黑胫病对全球油菜籽生产构成重大威胁。与病原体中的无毒基因相对应的抗性基因已被广泛用于减轻该病的影响。为了研究介导的对黑胫病抗性的生化基础，我们对一个易感的Topas双单倍体（DH）品系及其携带的同基因抗性对应品系在感染过程中的代谢组学图谱进行了基于液相色谱-质谱联用（LC-MS）的分析。样品用C和C标记用于LC-MS分析，以增强代谢物的化学和物理性质，从而提高定量和检测灵敏度。与模拟接种的Topas对照相比，抗性植株在接种的Topas植株中显示出几种防御代谢物的早期和持续积累，特别是哌啶酸（PA，高达326倍）、水杨酸（SA）和龙胆酸（GA）（调整后<0.05），表明赖氨酸降解和激素防御途径被激活。硫代葡萄糖苷（GLS）、γ-氨基丁酸（GABA）和褪黑素前体的升高可能进一步有助于抗菌防御和细胞壁强化。相比之下，类黄酮和苯丙烷途径被下调，表明在抗性过程中代谢重新分配。外源施用PA、SA、GA、阿魏酸和胡椒酸（植物中苯丙烷途径的已知抑制剂）显著降低了易感油菜品种的感染，验证了它们对黑胫病的防御作用。这些结果为介导的抗性提供了新的见解，并为油菜中培育持久抗黑胫病的代谢靶点提供了支持。
