ISTA CERTIFICATES VISAS FOR INTERNATIONAL SEED TRADING Only ISTA-accredited laboratories are authorised to issue ISTA Certificates for seed analysis. By reporting seed test results on ISTA Certificates the issuing laboratory assures that the sampling and testing has been carried out in accordance with the ISTA Rules. ISTA Certificates are accepted by many authorities and are mentioned into the Seed Act of several countries. The ISTA Certificates are assuring that the test results are reproducible true and represent the quality of the seed. An Orange International Seed Lot Certificate is issued when both sampling from the lot and testing of the sample are carried out under the responsibility of an ISTA-accredited laboratory.