Soluble Silicon Controls Fusarium Head Blight in Bread and Durum Wheat Plants

• Published in: Gesunde Pflanzen 2021-12, Vol.73 (4), p.479-493
• Main Author: Sakr, Nachaat
• Format: Article
• Language: English
• Subjects: Agriculture; Biomedical and Life Sciences; Bleaching; Blight; Bread; Cultivars; Disease; Foliar applications; Fungal diseases; Fusarium; Fusarium head blight; Inoculation; Life Sciences; Mycotoxins; Nutritional status; Original Article; Originalbeitrag; Plant Pathology; Reduction; Silica; Silica gel; Silicon; Silicon dioxide; Soils; Species; Species diversity; Spraying; Wheat
• ISSN: 0367-4223; 1439-0345
• DOI: 10.1007/s10343-021-00568-0

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 SiO 2 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.