Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is a devastating disease in rapeseed. The objective of this study was to investigate the role and the mechanism of silicon (Si) in alleviating the disease severity of S. sclerotiorum in rapeseed. In the absorption assays, the rapeseed that absorbed 10 mM of K₂SiO₃ exhibited an 86% decrease in lesion size on infected leaves as compared with controls. In the spray assay, the lesion length on rapeseed stems was reduced by 30.5–32.9% with the use of 100 mM of a foliar Si fertilizer as compared with controls. In the pot assay, the lesion length on rapeseed stems was reduced by 34.9–38.3% when using the Si fertilizer as basal fertilizer. In the field assay, both the disease incidence and disease index of sclerotinia stem rot were significantly reduced with the usage of a solid Si fertilizer, Si foliar fertilizer, and the application of both, without negative affection on the main agronomic traits and seed quality of rapeseed. The transcriptome sequencing, quantitative reverse transcription PCR (qRT-PCR), and biochemical assays between K₂SO₄- and K₂SiO₃- treated rapeseed leaves revealed that Si promoted the biosynthesis of defense-related substances and enhanced the antioxidation and detoxification abilities of rapeseed after infection. Thus, this study concluded that Si can alleviate the disease severity of S. sclerotiorum in rapeseeds, partially due to the induced defense responses.

菌核病茎腐烂，由 核盘菌，是油菜籽中的一种毁灭性病害。本研究的目的是研究硅（Si）在减轻疾病严重程度方面的作用和机制。核盘菌在油菜籽中。在吸收试验中，油菜籽吸收了 10 mM K ₂ SiO ₃与对照相比，受感染叶片上的病斑大小减少了 86%。在喷雾试验中，与对照相比，使用 100 mM 的叶面硅肥使油菜籽茎上的病斑长度减少了 30.5-32.9%。在盆栽试验中，当使用硅肥作为基肥时，油菜茎上的病斑长度减少了 34.9-38.3%。在田间试验中，固体硅肥、硅叶肥和两者的施用均显着降低了核盘菌茎腐病的发病率和病害指数，对主要农艺性状和种子质量没有负面影响。油菜籽。K ₂ SO ₄ - 和 K之间的转录组测序、定量逆转录 PCR (qRT-PCR) 和生化分析₂ SiO ₃ - 处理的油菜籽叶片表明，Si促进了防御相关物质的生物合成，增强了油菜籽在感染后的抗氧化和解毒能力。因此，本研究得出结论，Si 可以减轻疾病的严重程度。核盘菌 在油菜籽中，部分是由于诱导的防御反应。