Discovery of 2-Naphthol from the Leaves of Actephila merrilliana as a Natural Nematicide Candidate

This is the authors' abstract. We don't add key points for this paper.

To identify natural nematicides that can replace chemical nematicides, 2-naphthol with high activity against Meloidogyne incognita was isolated from Actephila merrilliana . The nematicidal activity of 2-naphthol against M. incognita was 100% at 100 μg/mL with an EC 50 value of 38.00 μg/mL. Moreover, 2-naphthol had a significant negative effect on egg incubation. 2-Naphthol effectively inhibited the invasion of M. incognita into crops in both a pot experiment and field trial. In addition, the structure–activity relationship indicated that the naphthalene ring and its β-site hydroxyl group were the key pharmacophores for the nematicidal activity of 2-naphthol. Nematodes were stimulated by 2-naphthol to produce excessive reactive oxygen species, which may be the underlying mechanism of 2-naphthol nematicidal activity. A systemic evaluation of 2-naphthol in tomato plants demonstrated that 2-naphthol remained mainly fixed in the roots after being absorbed by the crop and was not transported to the stems or leaves. Thus, 2-naphthol can be developed as a natural nematicide candidate.