Sampling Intensity in Wheat and Rice Seed Lots

Wheat and rice have high economic and food importance, making the use of seeds with proven physical and physiological quality essential. This study aimed to evaluate whether reducing sampling intensity changes the results of mandatory and complementary analyses used in the seed certification system. Sampling was performed in big bags from commercial wheat and rice seed lots, using four collection intensities corresponding to 100, 75, 50 and 25% of the recommended number of primary samples. The samples were analyzed at the Flávio Farias da Rocha Seed Laboratory, Federal University of Pelotas, for physical purity, determination of other seeds, inert material, germination and viability by the tetrazolium test. The results were compared based on the tolerances established in the Rules for Seed Testing, at 5% probability. No significant differences were observed among the evaluated intensities for the studied lots and cultivars. Thus, under the conditions of this study, sampling intensity could be reduced to 25% without impairing the interpretation of laboratory results.