The announcement that the Environmental Protection Agency (EPA) has granted registration for Monsanto’s YieldGardÒ Rootworm corn could be a big step for farmers in controlling one of the most corn-damaging insects in the United States. The registration approval allows the commercialization of the first biotech product designed to control corn rootworm for the 2003 planting season.

According to NC+ Hybrids Product Manager and agronomist Doug Gloystein, the YieldGard Rootworm corn hybrids should offer greater protection against corn rootworm than the technology currently being used. "Part of the problem with soil-applied insecticides is they may not be able to get down into the root zone where they need to be to control the rootworms. That placement is dependent on soil types and available moisture," Gloystein said. "There are a lot of variables that affect soil-applied insecticides. Variables that can be eliminated by having the genetic resistance in the roots themselves."

Gloystein anticipates a similar scenario that took place with the introduction of YieldGard corn borer hybrids. "Before we had the corn borer Bt products, farmers really didn’t know how much yield loss was being caused by corn borer because they weren’t really getting complete control with insecticides," he said. "I think we will see the same thing with YieldGard Rootworm hybrids in that the higher level of control is going to mean much better performance. Especially in areas where they have heavy rootworm infestations."

NC+ has an agreement with Monsanto to market YieldGard Rootworm corn products and has a limited amount of selected hybrids in winter production. While YieldGard Rootworm corn has received the necessary clearances in the U.S. and Japan, individual state approval within the United States is required before this product can be purchased or planted.

Gloystein says it is important for farmers to follow the Insect Resistance Management guidelines (refuge specifications) for YieldGard Rootworm and all Bt corn products. "There will be some restrictions, and farmer will want to follow those closely, because Bt corn is a valuable tool we don’t want to lose to resistance."

Gloystein added that the biggest improvement he expects to see is in YieldGard Rootworm corn is in its harvestability. "I’ve been in fields that have lost 40 percent or more of their yield potential because of corn rootworm damage," he said. "This is a result primarily from the lodging and poorly developed root systems caused by corn rootworms. As a supplier of YieldGard Rootworm, NC+ will be able to offer farmers a tool that gives them the opportunity to have the most complete rootworm control available."