Seed Quality Testing
What Lab Testing is Available?
Seed quality can be tested using the Standard Germination Test or the Accelerated Aging (AA) Test. These tests are inexpensive and can be conducted by the Arkansas State Plant Board.
Seed quality tests are assessed by a specially-trained seed analyst. Photo by Debby Monfort.
What Tests are Performed to Gauge Seed Quality?
Standard Germination Test
This test determines the percentage of seed capable of producing normal seedlings under optimal conditions.
Seed are placed in moistened germination towels, then held in a germination chamber for 6 to 8 days at either a constant 77-degrees Fahrenheit or under alternating temperature conditions of 16 hours at 86-degrees Fahrenheit followed by 8 hours at 68-degrees Fahrenheit for 6 days. The percentage of normal seedlings are determined based on standardized seedling characteristics.
POOR GERM VS. GOOD GERM: Soybean seed with poor germ (left) versus good germ (right). Good germ values are considered to be greater than 80%. Photo by Debby Monfort.
Accelerated Aging (AA) Test
This is a more recent standardized test used to estimate the vigor of seed and help predict seed performance under varying conditions at planting.
A precise amount of seed is measured and placed in a 100% humidity environment at 106-degrees Fahrenheit for 72 hours, after which the seed are subjected to the standard germination test.
The high humidity and temperature of the AA test stress the seed, and provides additional information about the overall quality of individual seed lots and where they could be used most reliably. Seed with germ above 80% and AA values above 65% indicates good seed quality, although no hard and fast AA thresholds have been established to date.
POOR AA VS. GOOD AA: Accelerated aging vigor testing exposes soybean seed to temperature extremes which can affect the seed's germination. Poor vigor (left) versus good vigor (right). Generally, seed with an AA value above 65% indicates good quality. Photo by Debby Monfort.
Demonstration Videos of Seed Quality Testing Methods
Acknowledgements: Videos were prepared by Julie Robinson and Sandy Goeke.