Volatile Organic Compounds From Nematophagous Fungi With Nematicidal Activity Against the Root‐Lesion Nematode Pratylenchus brachyurus

ABSTRACT Pratylenchus spp. are highly polyphagous migratory endoparasites and rank among the most important plant‐parasitic nematodes in agriculture. Their management relies primarily on integrated practices, including the use of chemical nematicides, biological control agents, and cultural strategies. Crop rotation is limited due to the broad host range of Pratylenchus spp., and the lack of effective resistance genes against P. brachyurus hampers the development of resistant cultivars. Although available chemical nematicides provide effective control, many have considerable ecotoxicological impacts, leading to usage restrictions or market withdrawal in several countries. In this context, the search for secondary metabolites with nematicidal activity for biocontrol development emerges as a promising and environmentally safe alternative. In the present study, volatile organic compounds (VOCs) produced by nematophagous fungi were evaluated for their ability to induce in vitro mortality of Pratylenchus brachyurus . Benzaldehyde (LC 50 = 454.9 μg/mL; LC 95 = 1472 μg/mL) and 1,3‐dimethoxybenzene (LC 50 = 520.4 μg/mL; LC 95 = 1878 μg/mL) were identified as the most active VOCs. In in vivo assays, both compounds inhibited the penetration of P. brachyurus into soybean roots. In both in vitro and in vivo experiments, benzaldehyde exhibited activity comparable to fluensulfone, a commercial nematicide used as a positive control. These findings suggest that both compounds hold promise as bioinputs for the management of P. brachyurus , either through direct application or in synergy with nematophagous fungi.