The weather is turning warmer and that can only mean one thing for those involved in agriculture; it is nearing planting time! Many have begun to ensure their planters are ready to roll by replacing disc openers and calibrating meters. We will soon be dumping seed into boxes to head off across the Home 80. Before you start planting this spring, it is imperative to know the quality of seed that is going into the soil. One of the most important things you can do before putting even one seed in the ground is to have your seed tested for germination and vigor.
The Federal Seed Act requires all seed companies to report a Warm Germination Score for all seed lots. This value is expressed as a percentage on all units of seed. The warm germ test simulates optimum growing conditions. Seeds are exposed to adequate temperature, humidity, and light. We are continually pushing planting dates earlier and aren’t always placing the seed in a favorable environment. A cold germ and super cold germ test will simulate the cold, wet field conditions that these earlier planted crops may experience. By placing the seed in a colder environment for several days, and exposing it to ideal temperatures thereafter, we are able to establish a cold germ percentage based on the seedlings that emerged. Hybrid vigor is then determined and can help to decide which hybrids will perform best for early plantings.
The Cold Germ test samples are placed in a cold chamber for 7 days at 50°F, whereas the Super Cold Germ test stresses the seed at 41°F for a 7 day period. The samples are then moved to a 77°F warm chamber to germinate. Seedlings are then evaluated according to Association of Official Seed Analysts (AOSA) rules for seed testing. A percentage is then determined for each lot of seed. Both tests are performed using a saturated roll towel method.
In the following example, you can see that the sample had a 98% Cold Germ score and a 98% Super Cold Germ score. The remaining seeds were either abnormal or dead. The abnormal seed had insufficient roots and shoots or split coleoptiles. This lot represents very high quality seed.
Example 2 shows a sample that has an 87% Cold Germ score and 82% Super Cold Germ score. The seed industry classifies a Cold Germ test of 85% or above with a good or passing score, and a Super Cold test of 75% or above as passing. This lot of seed falls within industry standards, however, would not be at the top of our list to be one of the first products in the ground come spring.
Margins today are very tight and every seed counts. In order to achieve the maximum economic yield potential, we need every seed to germinate and grow into a productive plant. A target population of 36,000 plants per acre and a Cold Germ score of 87% could result in the loss of almost 5,000 plants an acre due to seeds improperly germinating or not germinating at all. One thousand seeds has the potential to produce 7-10 bushels of corn. The loss of 5,000 seeds due to a lot with poor germination could result in a loss of 35-50 bushels per acre before the seed even went in the ground. This would equate to a loss of $120-200 per acre in today’s corn markets. A quality plant stand starts at germination and is essential in determining the maximum economic yield. Are you having your seed tested and analyzed for quality?