What is in this article?:
• The traits in cotton seed are relatively simple compared to those in corn, because they’re concerned only with caterpillars and herbicides.
• Corn seed also is becoming more expensive, causing growers to ask if they’re getting value for the extra cost.
• There are many changes this year in terms of seed treatments.
Trait for corn earworm control
Agrisure Viptera is a new product series that contains a second new trait (Vip3A) for caterpillars, especially corn earworm control.
Specific Viptera products have a number designation which for Southern hybrids will be 3110, 3111 and 3220. Depending on the product, it also may be stacked with one or two traits for corn borer and corn rootworm control as well as tolerance to glyphosate and glufosinate herbicides.
Optimum Intrasect by Pioneer is a new product for the Southern U. S. It contains the two original corn borer proteins, in YieldGard-CB and Herculex 1, but does not contain a rootworm trait.
This product provides very good to excellent control of corn borers and fall armyworm in the whorl, says Buntin.
It also provides partial reduction in kernel damage by corn earworm similar to that of YieldGard-CB. Optimum Intrasect XTRA also has the rootworm trait in Herculex XTRA.
For 2012, says Buntin, there will be several Bt products marketed for the Midwest corn belt that have a reduced 5 percent or 10 percent non-Bt refuge that is mixed or blended in the bag of a Bt product.
They include Genuity SmartStax RIB Complete, REFUGE ADVANCED Powered by SmartStax and Optimum AcreMax (several products).
These products will not be marketed in cotton areas of the Southern U.S., but if grown in cotton areas, they will still require a 20-percent non-Bt structured refuge.
Insecticide resistance management (IRM) is required for all Bt traits in corn and includes structured refuge of non-Bt corn, says Buntin.
Refuge requirements are different for the Northern Corn Belt and the Southern cotton-growing areas of the United States. Refuge requirements also differ among hybrids with one or more Bt traits.
“Single above-ground trait products require a 50-percent non-Bt refuge.
Most multiple above-ground trait products require a 20-percent non-Bt corn refuge. Starting in 2012, seed bag tags will have details about product IRM requirements, refuge amount and refuge placement options.”
The National Corn Growers Association has produced a refuge configuration calculator that can be downloaded to any computer.
It covers Bt traits for all of the types of Bt corn sold in the U.S. and can be found at www.irmcalculator.com. You can look up the type of Bt product you have, enter the state and the acreage, and the program will tell you how many acres of Bt and refuge non-Bt are needed and options for how it can be planted.
(Even though corn seed is becoming more expensive and hybrid selection decisions are more difficult, the higher prices for corn are making insect control more critical. For a discussion of that topic, see http://southeastfarmpress.com/grains/rising-prices-make-corn-insect-control-more-beneficial. On another subject, the sugarcane beetle does seem to be emerging as a pest in corn crops in the South. For a look at that situation, visit http://southeastfarmpress.com/grains/sugarcane-beetles-causing-problems-alabama-corn-growers).