The effects of weed control procedures, fertilizer and seed distribution uniformity, and young plant protection to insects over the experimental error were studied. The management procedures were organized in three experiments using a completely randomized design. Each replication of the management procedure was made by 6 lines of 5m using a short-day com cultivar. The weed control, made by herbicides or manual control did not present significam difference in the experimental error. The evaluation of the experimental error of the more uniform fertilizer distribution was smaller than the desuniform distribution. The line seed distribution, done by hand and not with the same distance, caused a smaller experimental error for grain yield and final population than the line seed distribution with the same distance.
precision; experimental error; experimental management
