Evaluation of natural chemical compounds against root-lesion and root-knotnematodes and side-effects on the infectivity of arbuscular mycorrhizal fungi

The survival of two species of plant parasitic nematodes: the root-lesion n ematode Pratylenchus brachyurus, and the root-knot nematode Meloidogyne jav anica, was evaluated in saturated atmospheres of 12 natural chemical compou nds. The infectivity of two isolates of arbuscular mycorrhizal fungi: Glomu s mosseae and Glomus intraradices, under identical experimental conditions, was also determined. All the compounds tested exerted a highly significant control against M. javanica and among them, benzaldehyde, salicilaldehyde, borneol, p-anisaldehyde and cinnamaldehyde caused a mortality rate above 5 0% over P. brachyurus. The infectivity of G. intraradices was inhibited by cinnamaldehyde, salicilaldehyde, thymol, carvacrol, p-anisaldehyde, and ben zaldehyde, while only cinnamaldehyde and thymol significantly inhibited myc orrhizal colonization by G. mosseae.