Pest pressures and proteins. What’s the link in sweet corn?
It’s the time of year when sweet corn growers begin thinking about and purchasing seeds for the upcoming growing season. A substantial part of that decision focuses on what pest pressures will come into play and which seeds hold up to those pressures best.
Common pests that many growers deal with each season include European corn borer, corn earworm and fall armyworm. These three lepidopteran insects can wreak havoc on a corn field and leave a grower with an enormous loss in yield and profit as they chew through ears of corn.
Effective methods for controlling these pests include planting sweet corn varieties with genes that express the production of a crystalline protein (Cry) from Bacillus thuringiensis (Bt). When lepidopteran insects consume a small amount of plant tissue from these varieties, the Bt protein binds to their digestive systems, causing them to stop feeding and die within 48 hours. Bt protein is embedded within corn leaves, silks, stalks and ears throughout the growing season, providing comprehensive protection that won’t wash off in the rain or degrade in the sun.
Attribute® II varieties include a trait stack that expresses the production of both Cry proteins and vegetative insecticidal proteins (VIP), an entirely new class of proteins. Vip3A binds to different receptors than Cry proteins within an insect’s mid-gut membrane, and can greatly reduce the risk of insect resistance.
Galen P. Dively, Professor Emeritus and IPM Consultant at the University of Maryland says, “Bt sweet corn clearly offers a more targeted and sustainable tool to control insect pests and significantly reduces the number of conventional insecticides. Based on multiple-year field trials, Attribute II hybrids reduced silk sprays for ear-invading caterpillars with multiple Bt proteins expressed that provide virtually 100% control of the pests. Other studies have not reported any adverse effects on beneficial insects in Bt sweet corn.”
Dively also confirms that, as a result of having minimal to no spraying, using Bt sweet corn generally results in cost savings over conventional control programs, and can significantly reduce the time that growers spend in managing lepidopteran pests, as well as reduce the exposure risk from handling and applying insecticides.
Contact your Syngenta sales representative or reseller for information about Attribute sweet corn varieties.
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