Susceptibility Assessments of Tomato Genotypes to Root- Knot Nematodes, Meloidogyne javanica

Root-knot nematodes, meloidogyne spp., are one of the important plantparasitic nematodes of tomato in the world. the most suitable control methodof plant parasitic nematodes is the use of resistance sources and tolerantcultivars. in the earlier studies, the results showed thatonly 2% (19 out of 537varieties) were resistant and tolerant to the root knot nematodes. in the supplementarystudies, the susceptibility of these 19 tomato cultivars were reassessedagain, against m. javanica, in the two completely randomized design experimentsin the greenhouse and field conditions for the two continuous years. thetomato plants were evaluated 70 days after inoculation on the basis of the gallindexes (gi), final populations (pf), reproduction factors (rf) and the root andor the stem weights. the results showed that, the cultivars no. 136 and 109with gi=2, rf=4.68 and gi=2.25, rf=28.4 are tolerant cultivars to thenematode, m. javanica in the greenhouse respectively. also, the cultivar no.100 was considered to be a susceptible one, with gi= 3.25 and rf= 0.97.whereas, in the field conditions, the cultivars 136 and 109 proved to betolerant with gi, 1.9 and 1.6 respectively.