In order to have a proper seed supply, it is essential to have a production program adjusted to the demand. Commercial seed usage by the farmer is indispensable information , as well as the seed quality supplied by the seed companies and the agronomic practices related to crop establishment. To estimate these values a drill box survey method was used. The samples were estimated allowing an error of 5%, and collected during the planting season proportionally to each region of the state of Paraná in the crop year 2002/03. The fields were visited at random, contacting the machine operator and collecting a sample of 1.0kg from the drill box. Besides collecting the seed samples, which were used for quality evaluations, additional information was obtained of which the most important was the origin of the seed that the farmer was using for planting. After seed quality evaluation and analysis of the data it was concluded that the commercial seed usage in the state of Paraná is in the range of 85-90%; less than 20% of the seed that is planted present low physiological quality; soybean growers from the state of Paraná are using high technology; and it seems that mechanical and weathering damage are the main causes for reducing the quality of the seed.
Glycine max; drill box survey; seed usage; seed quality
