International Seed Testing Association

In order to make data of different seed lots and species comparable, e.g. for marketing and research,tests must be standardized and replicable. The widely adopted methods of standarised seed testing follow the prescriptions of the International Seed Testing Association (ISTA). The ISTA rules contain, in addition to standard seed testing procedures, specific guidelines for a number of species. In addition 1ST A has published a number of more elaborate handbooks on individual seed testing procedures. Several American countries follow the Rules of Official Seed Analysts (AOSA), which, however differ only in minor aspects to the ISTA Rules.

ISTA is perhaps best known for developing and publishing the International Rules for Seed Testing. The document is a comprehensive set of instructions and techniques for the testing of seed and is used by seed analysts throughout the world. From the first version published in 1931, the Rules have been regularly updated, and the latest edition is ISTA Rules – 2006. The Rules include prescriptions for sampling seed, a wide range of quality tests, including purity, germination, viability, variety, seed health, and moisture content, and how to issue ISTA certificates. They are published in the three official ISTA languages (English, French and German) and have been widely translated (for example into Arabic, Mandarin, Russian and Spanish). Although the ISTA Rules are used throughout the world for testing seed sold in domestic markets, their main purpose from the ISTA point of view is in the issuing of fISTA Seed Analysis Certificates, which are widely used for international trading in seed.

There are three types of certificates:
- Orange International Seed Lot Certificate
- Green International Seed Lot Certificate
- Blue International Seed Lot Certificate