Tomato production may be dramatically reduced by root-knot nematodes, widely spread on horticultural areas. The interaction of arbuscular mycorrhizal fungi Glomus etunicatum and Gigaspora margarita and root-knot nematode, Meloidogyne javanica and their effects on growth and mineral nutrition of tomato (Lycopersicon esculentum) was studied under greenhouse conditions. Shoot dry matter yield was reduced by a nematode infection. The reduction was less pronounced in plants colonized with G. etunicatum (12%) than in plants colonized with G. margarita (32%) and nonmycorrhizal plants (24%). Plants colonized with G. etunicatum had the highest fruit number and fruit dry weight. Fruit production was less affected by the nematode in plants colonized with G. etunicatum. Shoot P concentration and content were not affected by M. javanica in plants colonized with G. etunicatum, but were reduced in plants colonized with G. margarita and nonmycorrhizal plants. Mycorrhizal plants had a higher number of eggs and juveniles of second stage (J2) of M. javanica than nonmycorrhizal plants. The higher tolerance of plants colonized with G. etunicatum to M. javanica appeared to be associated with P nutrition
