Suppression of rice blast and tomato late blight by Paraboeremia adianticola producing vulculic acid

Abstract BACKGROUND In the search for new natural resources with antifungal activity, the culture filtrate of the marine‐derive fungus Paraboeremia adianticola SFC20150402‐M24 showed excellent activity for controlling rice blast and tomato late blight diseases. This study aimed to (i) identify antifungal substances from the P. adianticola culture filtrate using chromatography and spectroscopy techniques and (ii) investigate the in vitro and in vivo antifungal activities of the isolated compound, along with its underlying antifungal mechanisms. RESULTS Based on chromatographic and spectroscopic analyses, vulculic acid was isolated and identified as a principal antifungal compound of P. adianticola SFC20150402‐M24. Among the tested eight fungal pathogens, vulculic acid completely inhibited the growth of Magnaporthe oryzae and Phytophthora infestans at concentrations of 6.3 and 200 μg mL −1 , respectively. This inhibition resulted in effective control of rice blast and tomato late blight. Furthermore, given that vulculic acid was more effective in inhibiting spore germination than the mycelial growth of M. oryzae , our results showed that vulculic acid has an effect on mitochondrial respiration with the downregulation of SdhC and Cox7A genes and inhibitory activity for electron transporter chain complexes II, III, and IV. CONCLUSION These findings highlight P. adianticola SFC20150402‐M24 and its production of vulculic acid as a valuable biological control agent for rice blast and tomato late blight. © 2025 Society of Chemical Industry.