Lauric acid exhibits antifungal activity against plant pathogenic fungi

This study aimed at examining the effects of the saturated fatty acid lauric acid on mycelial growth of Rhizoctonia solani and Pythium ultimum and on infection of barley seedlings with Blumeria graminis f. sp. hordei . Mycelial growth of R. solani and P. ultimum in agar culture was significantly reduced by lauric acid at concentrations of 100 mum and above, while no fungal growth occurred in liquid culture at concentrations above 50 mum. Application of lauric acid at concentrations ranging from 250 to 1000 mum to barley leaves before or after inoculation with B. graminis f. sp. hordei led to significant reductions in infection. This study provides the first report of the activity of lauric acid against plant pathogenic fungi and indicates the need for investigation of its mechanism of action.