Control of viral diseases using systemic resistance-inducing microbes and microbial metabolites/molecules is an established alternative strategy for inhibiting plant viruses. However, the mechanisms whereby virus infection is inhibited and restricted in plants expressing systemic resistance remains poorly understood. We have previously reported that an aqueous extract of the dry mycelium of Penicillium chrysogenum (DMP) can be used to protect tobacco plants against Tobacco mosaic virus (TMV). In this study, we investigated the effect of crude peptides derived from DMP (PDMP) in protecting Nicotiana glutinosa against TMV. The number and diameter of TMV lesions in plants pre-treated with PDMP were fewer and smaller, respectively, than those in control plants. The elevated expressions of PAL, PTI5, PR-1a, NPR1, PR-1b, and PDF1.2 detected in the induced and systemic leaves following PDMP treatment indicated that the PDMP induced basal and systemic resistance in N. glutinosa. Callose deposition and TMV-N gene-triggered hypersensitive response (HR) at the site of the TMV infection were identified as key factors restricting the movement of viruses. The levels of N gene transcripts, as well as those of the TMV-N gene-triggered HR-related genes HSR203J, AOXa, SIPK, and ZFT1 increased more rapidly after being challenged with TMV in N. glutinosa plants pre-treated with PDMP compared with the control plants. However, we detected no significant difference between PDMP-treated and control plants with respect to TMV-induced callose deposition, indicating that PDMP enhances the resistance of N. glutinosa against TMV by accelerating TMV-N gene-triggered-HR rather than by priming callose deposition.

使用诱导系统抗性的微生物和微生物代谢物/分子控制病毒性疾病是抑制植物病毒的既定替代策略。然而，在表达系统抗性的植物中抑制和限制病毒感染的机制仍然知之甚少。我们之前曾报道过，Penicillium chrysogenum (DMP)干菌丝体的水提取物可用于保护烟草植物免受烟草花叶病毒 (TMV) 的侵害。在这项研究中，我们研究了衍生自 DMP (PDMP) 的粗肽在保护Nicotiana glutinosa免受 TMV 侵害方面的作用。与对照植物相比，用 PDMP 预处理的植物中 TMV 病变的数量和直径分别更少和更小。PAL、PTI5、PR-1a、NPR1、PR-1b和PDF1.2在PDMP处理后诱导和系统叶片中的表达升高表明PDMP诱导了N. glutinosa的基础和系统抗性。TMV 感染部位的胼胝质沉积和 TMV - N基因触发的超敏反应 (HR) 被确定为限制病毒运动的关键因素。N基因转录物的水平，以及 TMV- N 的水平与对照植物相比，在用 PDMP 预处理的N. glutinosa植物中，在用 TMV 攻击后，基因触发的 HR 相关基因HSR203J、AOXa、SIPK和ZFT1增加得更快。然而，我们在 TMV 诱导的胼胝质沉积方面检测到 PDMP 处理和对照植物之间没有显着差异，表明 PDMP通过加速 TMV - N基因触发的 HR 而不是通过引发胼胝质来增强N. glutinosa对 TMV的抗性沉积。