GC-MS Analysis of Nematicidal Essential Oil ofMentha canadensisAerial Parts againstHeterodera avenaeandMeloidogyne incognita

The essential oil of Mentha canadensis aerial parts was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromaotography-mas spectrometry (GC-MS). A total of 36 components of the essential oil were identified. The major constituents in the essential oil of M. canadensis were menthol (28.8 %), α-pinene (16.4 %), menthone (12.7 %), α-terpineol (6.3 %) and limonene (5.5 %). Four active constituents (limonene, menthol, α-pinene and α-terpinol) were isolated from the essential oil of M. canadensis based on bioactivity-directed fractionation. The essential oil of M. canadensis aerial parts exhibited nematicidal activity against cereal cyst nematodes (Heterodera avenae) and root-knot nematodes (Meloidogyne incognita) with LC values of 385.7 μg/ml and 139.0 μg/ml, respectively. The isolated constituents, menthol and α-terpinol possessed nematicidal activity against H. avenae and M. incognita with LC50 values of 242.5 μg/ml, 190.3 μg/ml and 147.4 μg/ml, 115.2 μg/ml, respectively. The study indicated that the essential oil of M. canadensis aerial parts and its two major constituents, α-terpineol and menthol have a potential to be developed to a natural nematicides for the control of nematodes.