Optimum plot size for the application of treatments is among the recognized methods to reduce the experimental error. There are several methods for plot estimation based on different principles. The objective of this paper was to propose an alternative method for the estimation of optimum plot size for crops, compare it with classical methods and to identify which parameters their results are correlated with. Fruit yield data from four experiments with sweet pepper cultivated in a greenhouse were used to validate the proposed method. It was evaluated the yield accumulated in several harvests. The results obtained by the proposed method, denominated Maximum Distance Method, are consistent, but weakly associated with the results obtained by other classical methods. The optimal plot size estimated by the Maximum Distance Method is strongly influenced by the heterogeneity index of production that measures the correlation between the productions in contiguous plots. It still has the characteristics of being easy to apply, remains practically unchanged in the cumulative productions, adapting to crops with two or more harvests in the same plants, as in vegetable crops or forage experiments.
experimental precision; planning of experiments; heterogeneity index; Capsicum annuum L; multiple harvests
