Root-knot nematodes (RKN; Meloidogyne spp.) are the most destructive plant parasites in vegetable production and their control is very challenging. This study aimed to define the nematicidal activity of eugenol on different life stages at 33.75 to 1,000 ppm doses against the root-knot nematode Meloidogyne javanica (Treub) Chitwood, 1949. This work is the first to report the effect of eugenol on egg differentiation and its vapor and sublethal doses activities. Second-stage juveniles (J2) were dead (99.5-100%) after 48 hr of exposure at a dose of 500 ppm. At this concentration, eugenol inhibited more than 70% nematode hatching. Additionally, the use of eugenol at sublethal doses reduced the number of females per gram in tomato roots in a pot test, and also inhibited egg differentiation. To the contrary, no nematostatic effects were observed in nematode motility bioassays. The phenolic monoterpenoid eugenol described herein merits further study as potential nematicide against the rootknot nematode Meloidogyne javanica.
