In the Furrow
Review B.t. Refuge Guidlines for Corn
By Will Duffie County Extension Coordinator

Corn producers need to review the refuge guidelines before making final corn variety selections. This issue has arisen due to demand and the limited seed supply of many corn varieties for the 2007 growing season. The g r o w e r agreement that has to be signed to p l a n t transgenic crops needs not to be taken lightly. Remember that you are agreeing to follow the guidelines mandated by E.P.A.

Cotton growers are familiar with refuge planting guidelines for cotton containing the Bacillus thuringenesis (B.t.) gene. The two refuges commonly used in cotton are the 95/5 and the 80/20 options.

For individuals not familiar with the refuge, the current refuge is simply a block or strip of a crop that does not contain a B.t. technology for controlling the target insect pest(s).

The purpose of a refuge is to maintain a population of insect pests that are not exposed to the B.t. proteins.

The lack of exposure to the B.t.proteins allows susceptible insects nearby to mate with any

rare resistant insects that may emerge from B.t. corn or cotton.

Susceptibility to B.t. technology would be then passed on to their offspring, helping to preserve the long-term effectiveness of YieldGard Plus and Herculex technology in corn

Burke County corn growers need to be aware of the differences in refuge requirements for corn vs. cotton.

The U.S. is broke into two regions based YieldGard Plus and Herculex guidelines for planting corn. The two regions are the Corn Growing Areas and the Cotton Growing Areas. All of Georgia and South Carolina counties are considered Cotton Growing Areas.

This means that each grower may not plant more than 50% of their corn acres with a B.t. corn hybrid. Therefore growers need to revisit their intended corn hybrids prior to final booking.

Insect Resistance Management is a requirement when purchasing YieldGard Plus or Herculex corn hybrids, as mandated by the US Environmental Protection Agency (EPA). Continued use of the product depends on compliance with EPA registration conditions.

For more information on refuge guidelines for corn or cotton call the Burke County Extension Office at 706-554-2119.