ABSTRACT
The electrical conductivity is a seed vigor test used to assess seed quality and complement the germination test. The sample size required to estimate the average electrical conductivity of seeds is directly proportional to the variability of the data and desired reliability in the estimate. A suitable technique for sample dimension is the use of confidence intervals obtained by resampling. This technique has the advantage of not depending on the probability distribution of the data. The objective of this study was to estimate the sample size required for the individual electrical conductivity test in sunflower seeds. Seven lots of sunflower seeds were used: 3 lots of the cultivar Hélio 250, 2 of the BRS 323, and 2 of the BRS 324. The individual electrical conductivity test was conducted with each lot of 400 seeds, and the sample size was determined by the seed number from which the amplitude of the 95% confidence interval (AIC95%) was less than or equal to 15, 20, 25, 30, and 35% of the mean estimate. The sample size of 483, 257, 172, 115, and 85 seeds is sufficient to estimate the average of the individual electrical conductivity of sunflower seeds with an AIC95% equal to 15, 20, 25, 30, and 35% of the mean estimate, respectively, for all lots and soaking periods.
Key words
Helianthus annuus L.; vigor; sampling; experimental precision
