The cold test is one of the germination stress tests designed to evaluate seed vigor in a seed lot. The cold test is the primary vigor test used for corn.

The test involves sowing seed on field soil containing soil pathogens for 7 days at 10°C before being moved to 25°C for germination.

The number of normal seedlings that emerge is recorded as a measure of vigor.

Photo showing trays of seedlings demonstrating examples of high vigor vs low vigor seedlings.

High vigor / Low vigor