The present work had as objective to estimate the sample size in each crop, for experiments accomplished in plastic greenhouse with the culture of the cucumber of the type conserves, cultivate Mandarina, in which the weight of the total fresh mass of the fruits was evaluated. The cultivation was accomplished in the area of the Department of Fitotecnia - UFSM and it was constituted of six lines with twelve portions of five plants in each line. The test of Bartlett was applied to verify the homogeneity of the variances among the crops and among the lines inside of each crop. It was verified that in 7 of the 13 crops, the variances among the lines came homogeneous. The sizes of samples found among all the portions were 44 and 22 portions and 10 and 11 portions for line for the semi-widths of the average of 10 and 20%, respectively, to 5% of error probability.
sampling; restricted area; quality control; planning of experiments