Nematicidal activity of essential oils against rice root-knot nematode Meloidogyne graminicola

The nematicidal activity of twelve commercially available essential oils (EOs) was tested against rice root-knot nematode Meloidogyne graminicola in in-vitro bioassays. Out of twelve Eos tested, three EOs viz., basil oil, peppermint oil, and lemongrass oil showed more than 80% mortality of second stage juveniles (J2) of M. graminicola at 1% concentration after 24 h of incubation while the nematode mortality was recorded 100% after 96 h of incubation. These three EOs were found highly toxic to the J2 of M. graminicola with LC50 of 361.8, 226.2 and 805.9 ppm respectively after 96 h of incubation. The basil oil and lemongrass oil were highly effective in inhibiting the egg hatching of M. graminicola with 0% egg hatch in basil oil and 62% in lemongrass oil at 2000 ppm concentration as against 98% in control recorded after 16 days of incubation. Our results indicated that basil oil, peppermint oil, and lemongrass oil were highly effective against rice root-knot nematode M. graminicola and have a potential for use in the management of this nematode.