Pulse Crop Breeding and Genetics, Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada.
College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, Canada.
Planta. 2023 Mar 2;257(4):73. doi: 10.1007/s00425-023-04105-3.
Stemphylium botryosum alters lentil secondary metabolism and differentially affects resistant and susceptible genotypes. Untargeted metabolomics identifies metabolites and their potential biosynthetic pathways that play a crucial role in resistance to S. botryosum. The molecular and metabolic processes that mediate resistance to stemphylium blight caused by Stemphylium botryosum Wallr. in lentil are largely unknown. Identifying metabolites and pathways associated with Stemphylium infection may provide valuable insights and novel targets to breed for enhanced resistance. The metabolic changes following infection of four lentil genotypes by S. botryosum were investigated by comprehensive untargeted metabolic profiling employing reversed-phase or hydrophilic interaction liquid chromatography (HILIC) coupled to a Q-Exactive mass spectrometer. At the pre-flowering stage, plants were inoculated with S. botryosum isolate SB19 spore suspension and leaf samples were collected at 24, 96 and 144 h post-inoculation (hpi). Mock-inoculated plants were used as negative controls. After analyte separation, high-resolution mass spectrometry data was acquired in positive and negative ionization modes. Multivariate modeling revealed significant treatment, genotype and hpi effects on metabolic profile changes that reflect lentil response to Stemphylium infection. In addition, univariate analyses highlighted numerous differentially accumulated metabolites. By contrasting the metabolic profiles of SB19-inoculated and mock-inoculated plants and among lentil genotypes, 840 pathogenesis-related metabolites were detected including seven S. botryosum phytotoxins. These metabolites included amino acids, sugars, fatty acids and flavonoids in primary and secondary metabolism. Metabolic pathway analysis revealed 11 significant pathways including flavonoid and phenylpropanoid biosynthesis, which were affected upon S. botryosum infection. This research contributes to ongoing efforts toward a comprehensive understanding of the regulation and reprogramming of lentil metabolism under biotic stress, which will provide targets for potential applications in breeding for enhanced disease resistance.
茎点霉属改变小扁豆次生代谢，并且对抗性和感病基因型有不同影响。非靶向代谢组学鉴定出在对茎点霉属引起的疫病抗性中起关键作用的代谢物及其潜在生物合成途径。小扁豆中由茎点霉属（Stemphylium botryosum Wallr.）引起的疫病的分子和代谢过程在很大程度上尚不清楚。鉴定与茎点霉属感染相关的代谢物和途径可能为培育增强抗性提供有价值的见解和新的靶标。采用反相或亲水相互作用液相色谱（HILIC）与 Q-Exactive 质谱联用的综合非靶向代谢组学方法研究了 S. botryosum 感染 4 个小扁豆基因型后的代谢变化。在开花前阶段，用 S. botryosum 分离株 SB19 孢子悬浮液接种植物，在接种后 24、96 和 144 小时（hpi）收集叶片样本。用模拟接种的植物作为阴性对照。在分析物分离后，在正离子和负离子模式下采集高分辨率质谱数据。多变量建模显示处理、基因型和 hpi 对代谢谱变化有显著影响，反映了小扁豆对茎点霉属感染的反应。此外，单变量分析突出了许多差异积累的代谢物。通过对比 SB19 接种和模拟接种植物以及小扁豆基因型的代谢谱，检测到 840 种与发病相关的代谢物，包括 7 种 S. botryosum 植物毒素。这些代谢物包括初级和次级代谢中的氨基酸、糖、脂肪酸和类黄酮。代谢途径分析显示，11 个显著途径受到影响，包括类黄酮和苯丙烷生物合成，这在 S. botryosum 感染后受到影响。这项研究有助于全面了解生物胁迫下小扁豆代谢的调控和重编程，为培育增强抗病性提供潜在应用的靶标。
