Selenium Nanomaterials Enhance Sheath Blight Resistance and Nutritional Quality of Rice: Mechanisms of Action and Human Health Benefit.

In the current work, the foliar application of selenium nanomaterials (Se NMs) suppressed sheath blight in rice (). The beneficial effects were nanoscale specific and concentration dependent. Specifically, foliar amendment of 5 mg/L Se NMs decreased the disease severity by 68.8% in -infected rice; this level of control was 1.57- and 2.20-fold greater than that of the Se ions with equivalent Se mass and a commercially available pesticide (Thifluzamide). Mechanistically, (1) the controlled release ability of Se NMs enabled a wider safe concentration range and greater bioavailability to Se NMs, and (2) transcriptomic and metabolomic analyses demonstrated that Se NMs simultaneously promoted the salicylic acid- and jasmonic-acid-dependent acquired disease resistance pathways, antioxidative system, and flavonoid biosynthesis. Additionally, Se NMs improved rice yield by 31.1%, increased the nutritional quality by 6.4-7.2%, enhanced organic Se content by 44.8%, and decreased arsenic and cadmium contents by 38.7 and 42.1%, respectively, in grains as compared with infected controls. Human simulated gastrointestinal tract model results showed that the application of Se NMs enhanced the bioaccessibility of Se in grains by 22.0% and decreased the bioaccessibility of As and Cd in grains by 20.3 and 13.4%, respectively. These findings demonstrate that Se NMs can serve as an effective and sustainable strategy to increase food quality and security.