Soluble silicon (Si) plays a pivotal role in the nutritional status of a wide variety of field crops and helps them, whether directly or indirectly, counteract fungal diseases. There is a paucity of information about the effect of Si on reducing Fusarium head blight (FHB) disease in wheat. This study aimed to evaluate the function of Si supplied to bread (moderately resistant) and durum (susceptible) wheat plants via incorporation into soil and foliar spraying in conferring resistance against four FHB species. Resistance mechanisms possibly involved in reduction of disease incidence and disease severity measured at 7, 14, 21 and 28 days post inoculation (dpi) potentialized by this element were also suggested. A SiO₂ powder was applied to soil while liquid formulation of Si was used as foliar spray at the rates 0.00, 0.50, 1.50 and 3.00 g/kg and 0.0, 0.8, 1.7 and 3.4 mM, respectively. Si at all rates of application did not significantly (p ≥ 0.05) reduce the incidence and severity at 7 dpi. However, with the application of 1.50 g/kg of soil and 1.7 mM, a reduction of bleaching of spikes (19.4% and 17.5%, respectively, on bread, 14.6% and 12.3%, respectively, on durum at 28 dpi) and spikelets (17.9% and 16.9%, respectively, on bread, 17.6% and 17.0%, respectively, on durum at 28 dpi) was observed at 14 dpi and increased with time till 28 dpi, and the other rates did not. The results also revealed that plants treated with solid source of Si (1.50 g silica gel) suffered lower levels of disease incidence and severity as compared with those treated with foliar spray (1.7 mM). The Si effect appeared to be species-specific at 21 and 28 dpi. More importantly, the susceptible cultivar treated with silicon was as resistant as the moderately resistant cultivar without silicon at 14, 21 and 28 dpi. Considering that no effects of Si were observed during the initial infection stage up to 7 dpi, our results theoretically postulate that silicon triggers defense processes in wheat plants, acting as an elicitor, in the latest infection stages (14 till 28 dpi) to reduce disease incidence and severity with a diversity depending of FHB species through affecting mycotoxins synthesis. Si soil and foliar inputs could be a valuable tool in integrated management against FHB pathogens by reducing the disease development on wheat.

可溶性硅 (Si) 在各种大田作物的营养状况中起着关键作用，并有助于它们直接或间接对抗真菌病害。关于硅对减少小麦赤霉病（FHB）病害的影响的信息很少。本研究旨在评估通过掺入土壤和叶面喷洒提供给面包（中等抗性）和硬粒小麦（易感）小麦植物的 Si 对四种 FHB 物种的抗性的功能。还提出了可能涉及在接种后 7、14、21 和 28 天测量的疾病发生率和疾病严重程度降低的抗性机制（dpi）。由SiO ₂将粉末施用于土壤，而将硅的液体制剂用作叶面喷雾，用量分别为 0.00、0.50、1.50 和 3.00 g/kg 和 0.0、0.8、1.7 和 3.4 mM。Si 在所有施用率下均无显着性 ( p ≥ 0.05) 降低 7 dpi 的发生率和严重程度。然而，施用 1.50 g/kg 土壤和 1.7 mM 后，穗状花序（面包上分别为 19.4% 和 17.5%，在 28 dpi 的硬粒小麦上分别为 14.6% 和 12.3%）和小穗的漂白减少（面包上分别为 17.9% 和 16.9%，硬粒小麦上 28 dpi 分别为 17.6% 和 17.0%）在 14 dpi 时观察到，并随着时间增加直到 28 dpi，其他比率没有。结果还表明，与用叶面喷雾 (1.7 mM) 处理的植物相比，用固体 Si 源 (1.50 g 硅胶) 处理的植物的发病率和严重程度较低。Si 效应在 21 dpi 和 28 dpi 时似乎是物种特异性的。更重要的是，用硅处理的敏感品种在 14 时与没有硅的中等抗性品种一样具有抗性，21 和 28 dpi。考虑到在最初的感染阶段直到 7 dpi 没有观察到 Si 的影响，我们的结果理论上假设硅在最近的感染阶段（14 到 28 dpi）触发小麦植物的防御过程，作为诱导剂，以减少疾病通过影响真菌毒素合成，FHB 物种的多样性取决于 FHB 物种的发生率和严重程度。通过减少小麦病害的发展，Si 土壤和叶面投入可以成为针对 FHB 病原体的综合管理的宝贵工具。在最新的感染阶段（14 至 28 dpi）通过影响真菌毒素的合成来降低疾病的发生率和严重程度，具体取决于 FHB 物种的多样性。通过减少小麦病害的发展，Si 土壤和叶面投入可以成为针对 FHB 病原体的综合管理的宝贵工具。在最新的感染阶段（14 至 28 dpi）通过影响真菌毒素的合成来降低疾病的发生率和严重程度，具体取决于 FHB 物种的多样性。通过减少小麦病害的发展，Si 土壤和叶面投入可以成为针对 FHB 病原体的综合管理的宝贵工具。