The objective of this study was to evaluate the effectiveness of foliar application of various synthetic compounds and biological extracts against powdery mildew on wheat. Seed coats of winter wheat were treated by synthetical compounds (benzothiadiazole, salicylic acid, and glycine betaine) or by the extracts from plants (oak, giant knotweed, curcuma, and ginger). Then the seeds were planted using small-field experiments with powdery mildew infection (repetitions over a two-year period; experimental field in Ruzyne, Prague). Leaf area infection was measured and the Cumulative Proportion of Leaf Area Diseased (CPLAD) was calculated. Data were analysed using ANOVA (Tukey test, p≤0.05). Effectiveness of preparations varied 30 % to 72 % in 2008, and 25 % to... |