Sample Sufficiency for Estimation of the Mean of Rye Traits at Flowering Stage

The objective of this study was to determine the sample size to estimate the traits mean in cultivars and sowing times, at flowering of rye culture. Ten uniformity trials were performed combining two cultivars in five sowing times. In the flowering of culture, in 100 plants of each uniformity trial, eleven traits were evaluated. The descriptive statistics was calculated and it was determined the sample size to estimate the mean in levels of precision (amplitude of the confidence interval of 95% for 5, 10, …, 35% of the mean) by resampling with replacement. The cob length presented the lowest variability among the eleven traits and, consequently, smaller sample size in both cultivars and five sowing time. There is variability in the sample size to estimate the mean among the traits, cultivars and sowing times. The measurement of 425, 276, 189 and 138 plants in cultivar BRS Progresso and 642, 413, 285 and 211 plants in cultivar Temprano, are enough to estimate the mean amplitude of the confidence interval of 95% maximum of 20, 25, 30 and 35%, respectively, for all the traits and sowing times.