Wright_1984_Parasitology_88_375

The response of the plant parasitic nematode, Meloidogyne incognita (J2 stage) to avermectin B2a-23-one is triphasic, comprising an initial loss of locomotor activity where the juveniles remain sensitive to touch, a recovery phase and a final loss of activity where the juveniles are relatively insensitive to touch. In contrast, the acetylcholinesterase inhibitor, oxamyl, causes initial hyperactivity of juveniles followed by a progressive decline in movement. The addition of bicuculline and to a lesser extent picrotoxin, both antagonists of gamma-aminobutyric acid (GABA), blocks the action of avermectin on M. incognita.