The whole idea behind a cool or cold test is to evaluate the emergence of a seed lot in cold wet soils, which can cause poor field performance.

The cold test was developed to simulate these adverse field conditions and measure the ability of maize seeds to emerge. It is the most widely used vigour test for maize and other crops (soybean, sorghum) in North America and Europe (TeKrony, 1983; Ferguson, 1990: Hampton, 1992) and is also widely accepted by the seed industry in other parts of the world. The cold test is one of the oldest vigour tests (Isley, 1950; Hoppe, 1956). Source: International Seed Testing Association, Handbook of Vigour Test Methods, 3rd Edition 1995.

The Association of Official Seed Analysts (Association of Official Seed Analysts, Seed Vigour Testing Handbook, Contribution No. 32.) lists several uses for the results of this test:

  • Evaluate fungicide efficacy.
  • Select genetic material demonstrating ability to germinate in cold wet soil
  • Evaluate physiological deterioration resulting from prolonged or adverse storage, freezing injury, immaturity, injury from drying or other causes.
  • Measure the effect of mechanical damage on germination in cold, wet soil.
  • Select seed lots for early spring planting.
  • Provide basis for adjusting planting rates for individual seed lots.

Cold/Cool testing has seen much work on Canola varieties in Canada by Dr. Bob Elliot of Agriculture Canada.

Work has also been done with cold testing in Pea, Carrot, and Onion.

These tests usually have the seed placed in cold temperatures (5-10 degrees Celsius) for a period of time followed by a grow period. Then the seed is evaluated as to normal seedlings according to a germination test. At Seed Check Technologies Inc. we also categorize the seedlings further into more vigourous using more strict evaluation criteria. So both of these numbers are supplied on the Certificate of Analysis.

Remember it is important to support all vigour tests with a germination result. Adequate germination is the first requirement in choosing seed lots. The closer the percent normal and percent vigorous are to the germination; the better the seed is for use in cold spring conditions.