Optimal Plot Size in Experimentation with Clonal Cacao Seedlings

The cacao tree (Theobroma cacao L.) is a crop of great economic importance to Brazil and has undergone several breeding processes that, among other things, have made it possible to obtain several self-compatible genotypes, ensuring that there is no genotypic variation in the crop, with the differences observed in the plants being caused only by the environment. For this to continue, the proper and reliable execution of scientific experiments is essential, and quantifying the material needed to carry out these experiments, i.e., the plot size, is an important step. This requires a scientific justification for choosing the plot size. In the literature, various plot sizes are adopted in experiments with seedlings. Therefore, the objective was to determine the optimal plot size for experiments with clonal cacao seedlings. The method adopted was the modified maximum curvature method using a bootstrap resampling simulation with 2000 replacements. The genotypes CCN10, CCN51, CP2204, CP2176, PS1319, and PH16 were evaluated based on 13 morphological characteristics and three quality indices used in morphological characterization studies of seedlings. The optimal plot size for experimentation with cocoa seedlings is nine plants per experimental plot.