Corn and soybean seed treatments are shifting higher on the input list. The main reason is higher-value seed. In the past, seed treatments were just the pink stuff on corn, says Mark Jirak, Syngenta seed treatment crop manager. Today, it's a different story.
“There's more attention by the grower that every seed be protected at planting,” says Jirak.
In the past 10 years, the number and severity of soybean diseases has grown, making seed treatments more important. If you remove weather, more bushels are lost to disease than any other factor, says Jim Beuerlein, Ohio State extension soybean specialist.
The $3-5/acre seed treatment costs don't always yield returns in ideal growing conditions. But because you can't predict the weather, Beuerlein recommends soybean seed treatments regardless of variety, crop rotation, soil type, tillage and planting date. Diseases can do damage without symptoms. By the time signs appear, yield losses are already 7-10%.
The cooler soils and more disease and insect pressure in conservation tillage also increase the need for seed treatments. So do early planting, narrow rows, phytophthora, ineffective genes, increased worker safety and less environmental impact.
More seed treatment products are being offered for both crops.
Gustafson's Poncho, a seed-applied corn insecticide, was expected to be registered last month. And a label for the company's Yield Shield, a soybean fungicide, is expected any time, says Paul Holliday, product manager. Other labels are expected in the next couple years.
“A strong demand in the soybean-producing areas of the U.S. has us also looking at imidacloprid (Gaucho) on soybeans for control of bean leaf beetles and aphids,” says Holliday. Gaucho is currently registered for use on corn.
Syngenta's Cruiser, a systemic insecticide, was labeled for corn late last October. About 22 companies are using the product this planting season. Cruiser should be labeled for soybeans by 2005; it'll be effective on bean leaf beetle and soybean aphid. Cruiser also has the ability to reduce bean pod mottle virus, says Syngenta's Jirak.
Protégé, a corn fungicide, was labeled in early February. “It's a step change in control,” Jirak says. Protégé, combined with Maxim XL, is effective against pre- and postemergent rhizoctonia, fusarium and pythium. Due to the late labeling, Protégé is likely to be more readily available in 2004.
Apron RFC, a rhizobia-friendly concentrate, is about a year away from being released, according to Syngenta. The material mixes easily with inoculants and provides a lower rate than Apron Maxx RTA to mix with liquid inoculants.
Know the problems you're trying to control and match the strength of the product to the control, suggests Jirak. For example, higher rates of Cruiser protect against corn rootworm while high rates of Apron XL should be used in fields with histories of phytophthora.
Rob Rettig, with 2,500 acres near Napoleon, OH, compares seed treatments through Ohio State test plots planted on his farm.
Outside the test plots he uses Rival and Apron to control phytophthora and pythium. In other fields he adds a USDA-patented strain inoculant at planting, using a garden sprayer tank attached to the drill. The cost is about half that of other commercial products.
Rettig has found that seed treatments can be worth the investment — under the right circumstances.
Several years ago he planted the same variety in two fields half a mile apart.
“On one field there was no damage, and on the other field the stand was nearly wiped out,” he says. “On some farms seed treatments didn't pay a bit, and on others there were big returns.”