Abstract
The effect of Meloidogyne incognita race 1 at different population densities (0, 0.0625, 0.125, 0.25,... 256 eggs and juveniles/cm3 soil) on the growth of a rootstock (1103 Paulsen) and a cv. Italia of grapevine was studied in glasshouse experiment. One-year-old, self-rooted plants were transplanted into 1,200 cm3 plastic pots containing soil infested by M. incognita race 1 at different inoculum levels. Reproduction of M. incognita race 1 was significantly higher on cv. Italia than on the rootstock 1103 Paulsen. Tolerance limits (T) of 1.28 and 0.78 eggs and juveniles/cm3 soil were estimated respectively for 1103 Paulsen and Italia. Minimum relative plant growth of 0.55, 0.80 and 0.85, respectively for shoot length and node number increase and fresh top weight, were estimated for 1103 Paulsen; whereas values of 0.25, 0.50 and 0.60 were assessed for the cv. Italia. Nematode equilibrium density was 33.6 and 137.8 eggs and juveniles/cm3 soil, on 1103 Paulsen and Italia, respectively.