In order to study the dry matter production with age and seed production an experiment was carried out at the Centro Nacional de Pesquisa de Soja/EMBRAPA, Londrina, PR, Brazil. The soil used is classified as Latossolo Roxo (Eutrustox). Six fertilizer doses were use: 0-0-0; 1-1-1; 2-1-1; 1-2-1; 2-2-1; 2-0-0; (NPK), being 0 = 0; I= 45kg/ha; 2= 90 kg/ha (N, P(2)0(5), K(2)0) with four replications. The distant was of 0.80m between the lines and five plants per linear meter. Samples of the plants were taken at 14 days of interval from the emergence of the plants to the harvested. The authors concluded: a) the dry matter production was not affected by the fertilizers; b) the seed production was higher in absent of the use of fertilizers; c) the highest rate of growth occurred at 56 days after the emergence; d) the maximum of dry matter production occurred at 85 days after the emergence of the plants.