Relationship between population densities of Meloidogyne incognita and growth of resistant and susceptible tomato

Abstract

Yields of tomato (Lycopersicon esculentum Mill.) are greatly reduced by infestations of Meloidogyne incognita (Kofoid et White) Chitw., in southern Italy, especially in sandy soils (Di Vito, 1979). Investigations done under field condition in Apulia, established a tolerance limit to M. incognita of 4 eggs/ml soil for a susceptible tomato cultivar (Chico III) and a minimum relative yield of 0 (Di Vito et al., 1981). Similar results were obtained by Barker et al. (1980) in U.S.A. Nevertheless, there is little information on the relationship between population densities of Meloidogyne spp. at sowing or transplanting and yield of resistant tomato cultivars. Therefore, a glasshouse experiment was undertaken to study the effect of population densities of M. incognita on the growth of a susceptible and a resistant tomato cultivar.