Foliar and root applications of different silicon (Si)-based formulations were evaluated for their effects in reducing powdery mildew and promoting growth of wheat plants. X-ray microanalyses of treated plants revealed that root applications resulted in consistent deposition of Si in the leaves. In terms of powdery mildew control, root applications at 1.7 mM Si gave consistently the best results, reducing disease severity by as much as 80%, regardless of the product used. Although less effective than root applications, foliar treatments with both Si and nutrient salt solutions led to a significant reduction of powdery mildew on wheat plants. This suggests a direct effect of the products on powdery mildew rather than one mediated by the plant as in the case of root amendments. In our experiments, Si amendment, either through the roots or the leaves, did not increase plant growth. These results lead to the conclusion that Si is primarily, if not exclusively, absorbed by the root system and that such absorption by the roots is necessary for an optimal prophylactic effect.

Bread is a highly consumed food and an important source of nutrients in the diet of Canadians, underlining the need to improve its nutritional quality. The Food Quality Observatory (Observatory) aimed to evaluate the nutritional value of the sliced bread products available in Quebec (Canada), according to their grain type and main flour. Analyses included comparing the bread’s sodium content to Health Canada’s daily values (DV) and sodium voluntary targets, comparing the bread’s fibre content thresholds with the source of fibre mentioned, and assessing whether the main flour was associated with the nutrient content. The nutritional values of 294 sliced breads available in Quebec were merged with sales data (from October 2016 to October 2017), with 262 products successfully cross-referenced. The results showed that 64% of the breads purchased were ‘low’ in fibre (i.e., below 2 g per two slices), while 47% were ‘high’ in sodium (i.e., above 15% DV per two slices). Attention should be paid to 100% refined grain bread and to bread with refined flour as the main flour, since they are great sellers, while showing a less favourable nutrient content. This study shows that there is room for improvement in the nutritional content of Quebec’s bread offer, particularly regarding sodium and fibre content.