Investigations on fungicides. XXI. The fungitoxicity and systemic antifungal activity of some aromatic quaternary ammonium salts

Root application of certain quaternary ammonium salts, most notably tri-n-butyl-and tri-n-pentyl-4-chlorobenzylammonium bromides, to wheat seedings grown in water culture enhanced their resistance to powdery mildew (Erysiphe graminis) but not to brown rust (Puccinia recondita). Anti-mildew activity was much less apparent if the compounds were applied to sand- or soil-grown seedlings. Systemic activity is considered in relation to the fungitoxicity, phytotoxicity and growth-retardant activity of these compounds.