Increased corn demand and resulting higher corn prices have caused some growers to consider planting more corn-after-corn acres in 2007. Those who choose that route may have to shift their thinking regarding field challenges.

For instance, planting corn after corn holds the possibility of facing cool, wet soils at planting, increased disease and insect levels and high crop residue. Agronomists with Pioneer Hi-Bred International, Inc., say one way to manage these challenges is by selecting hybrids with high ratings for stress emergence, high residue suitability, resistance to leaf, ear and stalk diseases, and stalk and root strength.

“Choose the highest performing genetics with defensive traits required for a corn-after-corn production system,” says Steve Butzen, Pioneer agronomy information manager. “That is in addition to selecting hybrid maturities that match corn planting dates and seasonal growing degree units – while accounting for cooler soils and slower emergence under corn residue.”

Ratings to consider when planting corn-after-corn

Planting more corn-after-corn acres can lead to earlier planting dates. Earlier planting and reduced tillage can make the seedbed a hostile environment for stand establishment. Pioneer provides a stress emergence rating that characterizes the genetic potential of hybrids to emerge under stressful conditions – cold, wet soils or short periods of severe low temperatures.

Butzen adds that high-residue cropping systems, including no-till and strip-till, are increasing because of a desire to reduce input costs, manage more acres, conserve soil and moisture in dry areas and comply with government conservation programs

“High-residue fields typically have cooler, wetter soils at planting and higher disease levels,” notes Butzen. “This combination of factors can reduce stands, leaf health, stalk and ear quality and harvestable yield – but appropriate hybrids can overcome these issues.”

Pioneer researchers have assigned a High Residue Suitability rating to all Pioneer® brand corn hybrids. This rating gives customers guidance on selecting hybrids suitable to high-residue tillage systems.

The incidence and severity of corn diseases have increased in recent years due to build-up of crop residue. Pathogens survive in corn residue, and disease builds up over time. In fields with a history of leaf, ear or stalk diseases it is important to choose hybrids with resistance to these diseases.

In corn-after-corn situations, select Pioneer hybrids with resistance to common corn leaf diseases, including northern and southern leaf blight, gray leaf spot, common and southern rust and eyespot. Ear disease scores include Fusarium, Gibberella and Diplodia.

With more corn acres to harvest, stalks may need to stand longer. Overall stalk strength can be a hedge against late-season lodging. Stalk and root strength ratings also are available on all Pioneer hybrids.

In addition to selecting hybrids with good root strength, control of corn rootworm (CRW) is critical in corn-after-corn fields. Pioneer hybrids with the Herculex® RW and Herculex XTRA insect traits are highly effective for protecting against western, northern and Mexican CRW. Herculex XTRA provides additional protection against other corn-after-corn insects – European corn borer (ECB), western bean cutworm (WBC) and black cutworm (BCW). ECB and WBC are a concern for corn-after-corn fields because they overwinter in corn residue. BCW target high-residue fields for egg-laying as they migrate from the South.

For more information about these ratings and Pioneer corn hybrids best suited for corn-after-corn production in your area, contact your local Pioneer sales professional. In addition to your local sales professional, Pioneer offers a national network of agronomists to answer agronomic questions associated with corn-after-corn production.

Pioneer Hi-Bred International, Inc., a subsidiary of DuPont, is the world’s leading source of customized solutions for farmers, livestock producers and grain and oilseed processors. With headquarters in Des Moines, Iowa, Pioneer provides access to advanced plant genetics, crop protection solutions and quality crop systems to customers in nearly 70 countries. DuPont is a science-based products and services company. Founded in 1802, DuPont puts science to work by creating sustainable solutions essential to a better, safer, healthier life for people everywhere. Operating in more than 70 countries, DuPont offers a wide range of innovative products and services for markets including agriculture and food; building and construction; communications; and transportation.

® Registered trademark of Pioneer Hi-Bred International, Inc.

Herculex insect protection technology by Dow AgroSciences and Pioneer Hi-Bred. ® Herculex and the HX logo are registered trademarks of Dow AgroSciences LLC.