Acceleration of Sweet Corn Germination at Low Temperatures with Terra-Sorb or Water Presoaks

Early season sweet corn has a potentially greater market value than peak-season sweet corn. However, most sweet corn cultivars, especially the “super sweets”, do not germinate well at temperatures below 10°C. To determine if pregermination treatments could be an effective means to accelerate corn germination in cool soils, seeds were treated and then incubated at 4.4°, 7.2°, and 10.0°C. Treatments included seed presoaked in an aqueous preparation of Terra-Sorb GB (TS) or water for 24, 48, 72, and 96 hr before incubation. The cooler the incubator temperature, the greater were the differences among water, TS, and control treatments. Pretreatments with TS over 48 hr are not practical if seeds are to be planted with a mechanical planter because the radicles are elongated to the point of potential damage. A 24-hr TS presoak offers the potential for early germination without prior radicle emergence, which would allow the seed to be mechanically sown.