The objective of this work was to determinate the

relationship between initial density and final density of

Meloidogyne sp in tomato crop. The study was carried out at

León, Nicaragua during 2011. The variables measured were

number of nematodes at transplant, number of nematodes

at harvest time, height at maturity of plants and yield in

kilograms. Nematode extraction was performed through the

Baermann modified method. In the study, the initial density

(Pi) showed a positive linear correlation with the final density

(Pf). However, it was observed that when Pi was equal to

400 nematodes/100 g of soil, the reproduction factor was

increased to 3.64, on the contrary, when Pi was equal to 700

nematodes/100 g of soil, reproduction factor was reduced to

2.48. Pi was inversely correlated to weight of tomato fruits

and height of plants. Plants with 200 nematodes/100 g of soil

had fruit weight 2.19 kg and height 153.20 cm compared to

0.93 kg and 135.24 cm in plants with 600 nematodes/100

g of soil. There was a positive correlation between Pi and

Pf of Meloidogyne sp. in tomatoes. The populations of this

nematode, were inversely correlated with plant height and

fruits weight.

Keywords: phytoparasitic nematodes, root damage, root knot nematode, fruit weight reduction.