Just Chill – Chilling Injury in CornMay 13, 2014 | Category: Agronomy |
Early planted corn often faces the risk of chilling injury. This occurs when the seed is exposed to cold soil and water temperatures 6 to 24 hours after planting. As the seed imbibes water and begins germination, the kernels will swell and expand. This can cause damage by stretching or rupturing cell membranes and causing cell leakage if the kernels are too cold. If you find swollen kernels that do not germinate or halted growth of the radicle root or coleoptile after germination, those can be signs of chilling injury.
Long exposure to low temperatures reduces metabolism and vigour, and increases sensitivity to disease and seedling blights. Cold water can also be an issue during emergence and can cause deformation of the mesocotyl (corkscrew), stunting, leafing out underground and delayed emergence.
Chilling injury is more common in corn than beans. Research predicts most chilling injury occurs when temperatures are below 5°C (40°F). Soil temperatures above 10°C (50°F) are ideal, so if you can begin planting when soils are above 5°C and the forecast is for rising temperatures, you should be in good shape.
Seed treatments and inoculants can be beneficial when dealing with cool, wet soils and help to prevent disease infection and aid in early growth. The good news is that once the soil is fit, soil temperatures shouldn’t be a problem this year in most areas. I did soil temperatures yesterday in no-till corn, no-till soys and a worked piece, and they all ranged from 7-8.5°C.
Laura Johnston, CCA-ON, Maizex Seeds Yield Specialist, West Elgin County