October 12, 2007

Compliance with insect resistance management (IRM) requirements is very important to the success of the overall IRM program. The goal of this program is to prevent resistance to Bt toxins in Bt transgenic corn from developing in target insect pests (European corn borer and corn rootworm).

Initially, compliance was measured through the use of grower surveys; however, now random field visits are also conducted to monitor compliance. For example, farmers are selected from the pool of farmers that purchased Bt corn, contacted, and a date is scheduled for a field visit by an independent agent.

Planting records may be examined, refuge fields measured for size and distance from the Bt field, and plants tested for the expression of the Bt toxin. If found to be significantly out of compliance, the farmer is provided resistance management educational materials, aided in developing a resistance management plan, and revisited during the following year. If the farmer is found to be out of compliance the second consecutive year, the farmer will be denied sales of the product the next year.

Remember, the farmer has the most important job in maintaining the continued effectiveness of Bt corn and limiting the development of resistance. This job is following resistance management practices and reporting any possible product failure to their seed dealer or local extension personnel. With continued IRM compliance we will hopefully preserve Bt corn as an effective pest management tool well into the future.

Tom Hunt
Extension Entomologist
Haskell Agricultrural Laboratory, NEREC
Bob Wright
Extension Entomologist, Lincoln
Keith Jarvi
IPM Assistant, NEREC