Relationship between population densities of Meloidogyne incognita and yield of sugarbeet and tomato

A decline of sugarbeet (Beta vulgaris L.) and tomato (Lycopersicon esculentum Mill.) in Southern Italy is often associated with heavy infestations of Meloidogyne incognita (Kofoid et White) Chitw. (Di Vito, 1980). However, although this root-knot nematode is widely distributed, there is a lack of information on the relationship between population densities and yield in Italy. Two experiments were therefore carried out at Ginosa Marina, in the Province of Taranto, to determine the effect of M. incognita on the yield of sugarbeet and tomato.