The study looked at how different amounts of nitrogen fertilizer affect corn growth in a no-tillage system. They tested four nitrogen doses and found that higher doses led to increased grain yield. The efficiency of the fertilizer also improved with higher doses, reaching 65% with the highest dose. The plants adjusted their biomass production based on the nitrogen available, and the soil provided a significant amount of nitrogen to the plants. Overall, the study showed that corn can adapt its growth to the nitrogen levels in the soil.