Number of experiments for adaptability and stability analysis in maize by Lin and Binns method

ABSTRACT: The objective of this study was to determine the necessary number of experiments to analyze the adaptability and stability of maize cultivars (Zea mays L.) using the Lin and Binns method. Grain yield data extracted from 63 maize cultivar trials were used. Trials were divided in six groups of experiments, according to the cycle (early and super early) and the agricultural year (2002/2003, 2003/2004, and 2004/2005). In each group, from the set of all experiments (reference file) new data files were formed by combinations in groups of 2, 3, 4, ..., n-1 experiments, with a total of 10,683 files. For each file, the estimation of the adaptability and stability parameter (Pi) of the Lin and Binns method was calculated. To verify the degree of association of the estimates of Pi obtained with the combinations of experiments and with all the experiments (reference), Spearman correlation coefficient (r) was used. Number of experiments giving values of r≥0.80 in 100% of the combinations was considered sufficient. Seven experiments sufficed for the analysis of adaptability and stability of maize cultivars by the method of Lin and Binns.