The first 48 hours corn seed are in the soil is critical. If soil temperature is below 50 degrees Fahrenheit during this time, it can lead to chilling injury and ultimately reduced yield. Temperatures at this stage are critical because this is the time water rushes in the seed to rehydrate the cells. This process is called imbibition. If the water is cold, below 50 F, it can damage the cells and abort growth of the radicle (root) and coleoptile (shoot). Seeds may not germinate or may express reduced growth.
To determine the risk of chilling injury, check the soil temperature in the field.
1. Check average soil temperature for the last seven days.
2. Check the air temperature predicted for your areas for the next 48 hours after planting.
3. Test the soil temperature in your field. A meat thermometer works well for this. Take the temperature just before dawn (the coldest time of day) and at the depth the seed will be placed.
If soils are less than 50 F or are expected to fall during the 48 hours after planting, wait to plant.
To contact an expert in your area, visit http://expert.msue.msu.edu, or call 888-MSUE4MI (888-678-3464).