DEKALB LogoContinuous Corn

Continuous Corn Growers Can Minimize Challenges, Maximize Yield Potential

Continuous corn growers face additional challenges not encountered in a traditional corn-soybean rotation. To minimize these challenges and maximize the opportunity for high yields, growers need to carefully evaluate their hybrid choices for continuous corn productions.

No corn hybrid is perfect for every field situation. Each hybrid reaches maximum performance under a specific range of soil types, fertility levels, production practices and environmental conditions. When selecting a hybrid for planting into corn on corn, carefully evaluate:

Emergence scores

Planting into corn residue in reduced- or no-till fields requires more consideration than a corn-soybean rotation. A heavy mat of residue lying on the soil surface will keep the soil cooler and damper than a conventionally tilled soil. Therefore, select a hybrid that is noted for strong emergence and early-season growth in cold soils to help increase the likelihood of achieving maximum plant populations. Another potential planting issue may be uneven seed placement as the planter unit “bounces” over last year’s cornstalks. Preparing the soil correctly and managing the residue is critical to obtaining a uniform plant stand.

Disease tolerance

Plant leaf diseases such as gray leaf spot are more likely to be a concern in a continuous corn system because these diseases are able to “overwinter” on corn residue from year to year. Gray leaf spot is also more likely to be an issue in reduced- or no-till situations as all of the residue remains on the surface, providing inoculum. Carefully evaluate the gray leaf spot resistance score when selecting a hybrid for a corn-on-corn situation. Hybrids that are totally resistant to gray leaf spot are not available; however, corn hybrids do vary in their ability to tolerate this disease. While disease development is not prevented completely, partial plant resistance in some corn hybrids has the effect of slowing disease progress. Since gray leaf spot is principally a disease during mid- to late-season, resistance that simply slows disease progress can provide acceptable yields.

Insect Protection

Another critical pest for producers planting continuous corn may be corn rootworm. Western and northern corn rootworms have historically laid their eggs in corn residue. In certain areas of the Corn Belt, some rootworms are laying their eggs in soybeans; however, in all geographies, rootworms are known to lay eggs in cornfields. To control these pests, consider planting a hybrid that contains either YieldGard® Plus or YieldGard VT™ Triple technology. DEKALB hybrids containing in-plant protection from YieldGard technologies have observed yield protection advantage in the range of 5 to12 bushels per acre. Higher levels of yield protection have been observed under more stressful conditions, which include corn-on-corn scenarios. YieldGard Plus and/or YieldGard VT Triple corn seed provides maximum in-plant insect protection against corn rootworm, European corn borer and a wide spectrum of corn insect pests. If a grower chooses not to use this technology, he should consider using a granular or liquid insecticide for control of corn rootworms and other insect pests in corn on corn situations.

Producing high-yielding corn in a continuous corn system may require some additional management. However, a grower can increase his chances of maximum yield by providing a good seedbed and selecting a high-yielding hybrid with strong emergence, good disease tolerance and built-in insect protection.

DEKALB offers a wide selection of corn products that can be planted successfully in a corn-on-corn situation. For a list of corn products that are recommended for corn in your area, please contact your local DEKALB dealer or visit www.DEKALB.com.

Related Resources

The following information is current as of September 30, 2007: YieldGard Plus, YieldGard Rootworm with Roundup Ready Corn 2 and YieldGard Corn Borer with Roundup Ready Corn 2 are grandfathered for import and use in processed feed in the E.U. YieldGard Plus with Roundup Ready Corn 2 , YieldGard VT Rootworm/RR2 and YieldGard VT Triple are neither approved nor grandfathered and there is zero tolerance for these traits in processed feed imported in the E.U. Growers of all products bearing the Market Choices mark must talk to their grain handler to confirm the handler's buying position for grain from these products. It is a violation of national and international law to move material containing biotech traits across boundaries into nations where import is not permitted.

YieldGard corn products are not yet registered in all states. Chick with your Monsanto representative for the registration status in your state.

Always Read and Follow Pesticide Label Directions. Roundup Ready® crops contain genes that confer tolerance to glyphosate, the active ingredient in Roundup® agricultural herbicides. Roundup® agricultural herbicides will kill crops that are not tolerant to glyphosate. We Breed Better Beans™, Roundup®, Roundup Ready®, YieldGard®, YieldGard VT™ and Design, and YieldGard VT Triple™ are trademarks of Monsanto Technology LLC. DEKALB®, Strong Roots. Strong Yields.®, and DEKALB® and the Winged Ear Design are registered trademarks of DeKalb Genetics Corporation. ©2007 Monsanto Company.