College of Forestry, Sichuan Agricultural University, Chengdu 611130, China.
Key Laboratory of Forest Protection of Sichuan Education Department, Sichuan Agricultural University, Chengdu 611130, China.
Int J Mol Sci. 2023 Sep 29;24(19):14761. doi: 10.3390/ijms241914761.
Chinese pepper rust is a live parasitic fungal disease caused by , which seriously affects the cultivation and industrial development of . Cultivating and planting resistant cultivars is considered the most economical and environmentally friendly strategy to control this disease. Therefore, the mining of excellent genes for rust resistance and the analysis of the mechanism of rust resistance are the key strategies to achieve the targeted breeding of rust resistance. However, there is no relevant report on pepper rust resistance at present. The aim of the present study was to further explore the resistance mechanism of pepper by screening the rust-resistant germplasm resources in the early stage. Combined with the analysis of plant pathology, transcriptomics, and metabolomics, we found that compared with susceptible cultivar TJ, resistant cultivar YK had 2752 differentially expressed genes (DEGs, 1253 up-, and 1499 downregulated) and 321 differentially accumulated metabolites (DAMs, 133 up- and 188 down-accumulated) after pathogen infection. And the genes and metabolites related to phenylpropanoid metabolism were highly enriched in resistant varieties, which indicated that phenylpropanoid metabolism might mediate the resistance of . This finding was further confirmed by a real-time quantitative polymerase chain reaction analysis, which revealed that the expression levels of core genes involved in phenylpropane metabolism in disease-resistant varieties were high. In addition, the difference in flavonoid and MeJA contents in the leaves between resistant and susceptible varieties further supported the conclusion that the flavonoid pathway and methyl jasmonate may be involved in the formation of Chinese pepper resistance. Our research results not only help to better understand the resistance mechanism of rust but also contribute to the breeding and utilization of resistant varieties.
花椒锈病是由引起的活体寄生真菌病害，严重影响花椒的栽培和产业发展。培育和种植抗性品种被认为是控制该病害最经济和环保的策略。因此，挖掘锈病抗性的优异基因和分析锈病抗性机制是实现锈病抗性定向选育的关键策略。然而，目前尚未有关于花椒锈病抗性的相关报道。本研究旨在通过早期筛选锈病抗性种质资源，进一步探索花椒的抗性机制。结合植物病理学、转录组学和代谢组学分析，我们发现与感病品种 TJ 相比，抗病品种 YK 在病原菌感染后有 2752 个差异表达基因（DEGs，1253 个上调，1499 个下调）和 321 个差异积累代谢物（DAMs，133 个上调，188 个下调）。抗病品种中苯丙烷代谢相关的基因和代谢物高度富集，表明苯丙烷代谢可能介导了花椒的抗性。实时定量聚合酶链反应分析进一步证实了这一发现，表明抗病品种中苯丙烷代谢相关核心基因的表达水平较高。此外，抗病和感病品种叶片中类黄酮和 MeJA 含量的差异进一步支持了类黄酮途径和茉莉酸甲酯可能参与形成花椒抗性的结论。我们的研究结果不仅有助于更好地理解花椒锈病的抗性机制，还有助于抗性品种的选育和利用。
