Pathogenicity of Meloidogyne javanica on common bean (Phaseolus vulgaris L.) in pots.

The relationship between a geometric series of 16 initial population densities (Pi) of Meloidogyne javanica between 0 and 1024 eggs and second stage juveniles (J2)/cm3 and growth of common bean (Phaseolus vulgaris) was investigated in pots in a greenhouse. The Seinhorst model, y = m + (1 - m)z P-T, was fitted to plant height, fresh root and top weight. Tolerance limits (T) to the nematode for plant height, fresh top weight and root weight of common bean were 1.7, 0.6 and 1.3 eggs and J2/cm3 soil, respectively. The minimum relative yields were 0, 0 and 0.2 at P magg/uguale 256 eggs and J2/cm3 soil for fresh top weight and root weight and height, respectively. Maximum nematode reproduction rate was 307-fold at the lowest initial population density.