Nematicidal activity of the essential oil from Cinnamomum cassia and (E)-cinnamaldehyde against phytoparasitic nematodes

The activity of Cinnamomum cassia essential oil (EO) and (E)-cinnamaldehyde was investigated on the phytoparasitic species Meloidogyne incognita, Globodera rostochiensis, and Xiphinema index. Juveniles (J2) or eggs of M. incognita and G. rostochiensis and mixed-age specimens of X. index were exposed to 12.5–100 µg mL⁻¹ concentrations of the two products. The suppressiveness of soil treatments with 100–800 mg kg⁻¹ soil rates of the C. cassia EO and (E)-cinnamaldehyde to M. incognita and G. rostochiensis was assessed on potted tomato and potato, respectively. A 24-h exposure to a 12.5 µg mL⁻¹ solution of (E)-cinnamaldehyde resulted in more than 68% mortality of M. incognita J2, while a poor mortality occurred at the same concentration of the whole EO. The mortality of G. rostochiensis J2 ranged 39 and 42%, respectively, since after a 4-h exposure to a 12.5 µg mL⁻¹ solution of both products. All the X. index specimens died after a 48- and 8-h exposure to a 100 µg mL⁻¹ solution of the EO and (E)-cinnamaldehyde, respectively. Egg hatch was reduced by more than 90% after exposing the M incognita egg masses or the G. rostochiensis cysts to 800 µg mL⁻¹ concentration of both EO and (E)-cinnamaldehyde for 24 and 96 h, respectively. The infestation of M. incognita and G. rostochiensis on tomato and potato, respectively, was significantly reduced by all soil treatments with both products, though (E)-cinnamaldehyde generally resulted more suppressive than the whole EO to both nematode species. According to these results, C. cassia EO and (E)-cinnamaldehyde could be suggested as a potential source of new environment-friendly nematicides.