Corn yield is dependent on individual plant growth and stand density. Reduced plant biomass and increases in plant-plant variability are expected responses to crowding, even though the role of nutrients in this process is poorly understood. Our objective was to evaluate alometric models for corn under different nutrition environments generated through direct and residual responses to N, P, S, in two crop rotations: corn-double cropped wheat/soybeans (C-W/S; two sites), and corn-full season soybeans-double cropped wheat/soybeans (C-S-W/S; two sites). The CREA Southern Santa Fe nutrition network, eleven on-farm fertilization experiments, was established in 2000 in the central Pampas of Argentina. Fertilization was annually applied to corn, wheat or full season soybeans (no N was applied) always in the same plots with nutrient rates equivalent to grain nutrient removal + 10%%, except for N. Rates of N were estimated from high-yielding N experiments in the region. Treatments included: 1) PS; 2) NS; 3) NP; and 4) NPS. During the 2006/07 season, alometric models were used for non-destructive estimations in corn, Shoot biomass evolution presented a close relation with stem volume along the pre-silking period (V6-R1), whereas during post-silking period, the correlation fitted better with the square of apical ear diameter. At beginning of grain filling (R3), ear biomass was significantly related with ear volume and shoot biomass at V13. Plant biomass and apical ear rate growth increased along the ontogenic stages, NPS treatments were the highest for all experimental sites. Interplant competition started very early in the cycle, more important differences were observed 500º C day (V7-8; AW 190 MG) from sowing. Plant-plant variability was inferred from an increase in coefficient of variation (CV) of plant biomass, this parameter increased for all treatments from sowing to V7-8. During the corn crop cycle, the NPS treatment presented the lowest CV values.