Inhibition of Fusarium oxysporum f. sp. nicotianae Growth by Phenylpropanoid Pathway Intermediates

Fusarium wilt in tobacco caused by the fungus Fusarium oxysporum f. sp. nicotianae is a disease-management challenge worldwide, as there are few effective and environmentally benign chemical agents for its control. This challenge results in substantial losses in both the quality and yield of tobacco products. Based on an in vitro analysis of the effects of different phenylpropanoid intermediates, we found that the early intermediates trans-cinnamic acid and para-coumaric acid effectively inhibit the mycelial growth of F. oxysporum f. sp. nicotianae strain FW316F, whereas the downstream intermediates quercetin and caffeic acid exhibit no fungicidal properties. Therefore, our in vitro screen suggests that trans-cinnamic acid and para-coumaric acid are promising chemical agents and natural lead compounds for the suppression of F. oxysporum f. sp. nicotianae growth.