The establishment of optimum plot size, in any culture, is one of the ways to increase experimental precision and maximize the information obtained in an experiment. The aim of this study was to determine the optimum size of plots for experiments with radish for the variables mass and root diameter. A test of uniformity was conducted with the planting of radish carried out in lines spaced at 15 cm to 5 cm between plants. The basic unit was defined as a linear segment of three consecutive plants. After 30 days of planting, mass (g) and diameter (mm) of radishes were evaluated. We simulated 35 sizes of plots, estimating mean and coefficient of variation for each size of plot and, using different nonlinear models, we determined the optimum size of plot for assays with radish. It was observed that the methods of modified maximum curvature and targeted linear and quadratic response models estimated different sizes of plot; therefore, in experiments with radish culture, plots with 21 to 63 plants (0.1575 to 0.4745 m²) per plot are recommended.
Raphanus sativus L; experimental material and precision; variation coefficient; uniformity essay
