January 3, 2001

USDA's Grain Inspection, Packers, and Stockyards Administration (GIPSA) has recommended that all seed corn to be sold for the 2001 planting season and parent lines to be used in 2001 seed production be tested for the presence of the Cry9C protein (StarLinkTM). This recommendation was prompted by the detection of Cry9C protein in non-StarLinkTM corn hybrid seed, GIPSA told seed companies in a letter.

The American Seed Trade Association (ASTA), Washington, said USDA advised that any seed corn that tests positive for the Cry9C protein should not be sold for planting purposes and be redirected for feed or non-food industrial uses. USDA also called for providing customers, upon request, with verification that the seed corn being sold was tested for the Cry9C protein in accordance with a testing program equal to or exceeding the performance of the attached GIPSA sampling and testing recommendations.

USDA's recommended sample size is 2,400 seeds, using GIPSA-validated tests manufactured by Strategic Diagnostics and EnviroLogix Inc. These tests detect one in 400 corn kernels (0.25%) and one in 500 kernels (0.2%), respectively, therefore, six tests of 400 kernels each or five tests of 500 kernels each will be needed to meet the recommended sample size of 2,400. The sample size is consistent with the Food and Drug Administration's recommendation for sampling and testing yellow corn and milled yellow corn, which was issued on Dec. 28, according to ASTA.

Other testing methods are commercially available providing a wide range of detection capability. However, caution must be taken to ensure that the sample size analyzed is consistent with the detection capability of the methodology used. GIPSA offers StarLinkTM testing services and guidelines for seed company testing procedures, ASTA added. The guidelines may be obtained from GIPSA at 202-720-0252 or online at http://www.usda.gov/gipsa.