Nematode-antagonistic effects of Cinnamomum aromaticum extracts and a purified compound against Meloidogyne incognita

Abstract

The potential use of Cinnamomum aromaticum and its active compound to control Meloidogyne incognita was investigated in vitro and in pot experiments. One compound, cinnamyl acetate, was isolated by thin layer chromatography and silica gel column chromatography, and identified by 1H-NMR, 13C-NMR and mass spectrometry. Juvenile movement and hatch inhibition by cinnamyl acetate was dependent on both the concentration and incubation time of the cinnamyl acetate. Treatment with 25, 50, 75, 100 and 125 μg ml−1 of cinnamyl acetate resulted in 33.7, 65.1, 81.1, 100 and 100% inhibition of movement of second-stage juveniles, respectively, at 50 min after incubation. The juvenile movement inhibition was <20% at the tested concentrations at 10 min after incubation. Cinnamyl acetate treatment resulted in 20.8, 39.4, 81.3 and 90.7% hatch inhibition at 25, 50, 100 and 200 μg ml−1, respectively, at 3 days after incubation and 21.6, 39.3, 73.2 and 88.7% hatch inhibition at 25, 50, 100 and 200 μg ml−1, respectively at 6 days after incubation. In pot tests, C. aromaticum crude extracts effectively inhibited infection of M. incognita on cucumber plants. Cinnamomum aromaticum crude extracts applied at 0.5 and 1.0 mg (g soil)−1 significantly reduced the numbers of galls caused by M. incognita. The activities of pathogenesis-related proteins as β-1,3-glucanase and peroxidase on leaves of plants treated with C. aromaticum crude extracts were significantly higher than those on leaves of control plants.