Cold temperatures don't worry some Midwest corn producers. All they do is get a coat for their corn and hop on the planter. The “coat” refers to corn seed protected from the elements by a film of temperature-activated polymers. The technology allows producers to plant corn as much as four weeks before normal planting dates with no deterioration in seed vigor.
The Intellicoat Early Plant technology is being tested in the Midwest and in the Bootheel of Missouri and in extreme southern Kentucky. There are no test sites in the deep Mid-South as of yet, but interest in the technology here is growing.
The polymer coating is applied to corn seed with a specialized film coater and marketed and sold through Fielders Choice Direct, a hybrid seed corn company, according to Tom Crowley, president of Landec Ag, which owns the polymer technology.
Seed with the coating can sit in cold, wet conditions for several weeks with no adverse effects, according to Crowley. “Below a certain ground temperature, the polymer coating is impermeable to water. Above that temperature, which can be pre-programmed for any seed, the polymers change to an amorphous state. The coating still stays hard, but instead of being crystalline where the carbons are connected, it opens up and allows water and moisture to get into the seed (for germination).
“The idea is that you can put this on seeds and plant into cold soils and give farmers three to four more weeks of window to get their crop planted.”
Emergence of the seed depends entirely on soil temperature, whether that is three weeks after the seed is planted or three days.
The longest seed remained un-germinated in the soil before emerging occurred in Wisconsin, according to Crowley.
“The farmer planted it on April 16. After April 16, it turned cold and started raining. The seed was in the ground 44 days before it warmed up. The farmer thought the seed was gone, but it came up to a full stand.”
The coating has been tested by 650 farmers on about 20,000 acres, according to Crowley. In all situations, the seed was planted into soil temperatures that were less than ideal, but a high percentage eventually emerged and no replanting was required.
“That was good news,” said Crowley, “but in a way it wasn't because we haven't found out how early you can go. But most people aren't going to go more than three weeks prior to when ideal conditions arrive. They're just unprepared to do that.”
The polymer technology is also being tested on soybeans which could allow Midwestern farmers to double-crop wheat and soybeans, according to Crowley.
Instead of a temperature activated polymer, the coating for the soybean seed is a “delay switch” based on heat units and is more time sensitive, according to Crowley. “The coated soybean is planted in the wheat when the wheat is about 12 inches high. The coating delays the germination of the soybean seed for about 25 days. When the wheat is harvested, the beans are coming up, but they're only about 8 inches high, so the harvester doesn't clip the beans. They're able to get about 65 bushels of wheat and 30 bushels of beans.”
Across 33 on-farm yield trials conducted by the company on 3,000 acres in 2001, coated seeds planted early out-performed uncoated seeds planted early by 6 bushels and uncoated seeds planted during normal planting dates by 5 bushels. Four to six hybrids were selected for the study.
For most producers, the advantage of the coated seed is adding three to four weeks to the planting window, noted Crowley.
In an emergence study of coated versus uncoated seeds planted early, 91 percent of the protected seed germinated compared to 65 percent for uncoated.
The cost of the seed coating for corn is $35 per bag, about $11 per acre, according to Crowley.
While the Intellicoat system has been targeted for the Midwest states, “we have been seeing some interest in the South,” Crowley said.
Landec Ag is also looking at the possibility of introducing seed coating technology to cotton, according to Crowley. “Early-planted cotton is something that would be very desirable for farmers.”