Herculex® I insect protection for corn, co-developed by Dow AgroSciences and Pioneer Hi-Bred is a superior example of the use of a natural Bt protein. The Bt protein (Cry1F) produced in corn with the Herculex I trait offers the broadest spectrum of above-the-ground insect pest control on the market. These pests include European corn borer, southwestern corn borer, black cutworm, western bean cutworm, lesser corn stalk borer, southern corn stalk borer, sugarcane borer, corn earworm and fall armyworm.
Insect infestation of crops severely impacts the health of the plants, reducing yield (measured in bu/acres) and grain quality. Major pests for corn are European corn borer, western bean cutworm, black cutworm and corn rootworm. The European corn borer alone destroys an estimated $1 to $2 billion worth of corn each year.
Insects cause many other forms of damage when they feed on parts of the corn plant, including breakage of the plant, eardrop and kernel damage. Damaged kernels can lead to growth of fungi, which may produce biologically active compounds called mycotoxins (e.g. aflatoxin, fumonisin). Dependent upon their accumulation in kernels, mycotoxins pose a potential threat to human and animal health if consumed.
Corn with the Herculex I trait provides many benefits for farmers, including improving yield and reducing the need for spray pesticides.
In field tests, corn hybrids with Herculex I insect protection averaged 8.3-13.9 bu/acres more than the same hybrids without protection. This means an increased yield of 5 to 9 percent for farmers.
With Herculex I insect protection, farmers can use fewer spray pesticides. For years, farmers have used sprays to fight insects. Use of these sprays can be time consuming, costly and not always effective. The pesticide application for corn borers, for example, has to be done during the short period between the time the caterpillars hatch and when they bore into the stalks where the pesticide doesn't reach them.
It has been long known that a common soil bacterium called Bacillus thuringiensis (often referred to as Bt) produces proteins (often referred to as Bt proteins) that kill specific insect larvae. Many of these proteins are found in crystals formed by the bacteria during one stage of its lifecycle. These are referred to as "Cry" proteins. The insecticidal activities of many Bt and Cry proteins have been studied in great detail and the majority are very specific, affecting only certain insects. Studies of many Bt bacterial strains, as well as their Bt proteins, have shown them to be harmless to other animals and humans. In fact, numerous spray formulations containing either Bt bacteria or Bt proteins have been used for more than 40 years for crop protection, including organic farming operations, and have been approved as an insecticide by the EPA.
Researchers have isolated the genes responsible for making the Bt proteins and transferred them into corn plants. Compared to conventional chemicals, these plants with the Bt protein provide insect protection much more effectively.
In addition to insect protection, corn with the Herculex I trait also provides protection against the herbicide glufosinate (Liberty®) by the use of a bacterial protein, generally referred to as PAT.
Following U.S. federal agency guidelines, Herculex I went through extensive testing and regulatory evaluation for food, feed and environmental safety prior to commercialization. An overview of the Herculex safety assessments is available is this section. For more information on the regulatory processes in the U.S. and other countries, go to The Safety of Biotech page of this website.
Herculex Insect Protection technology by Dow AgroSciences and Pioneer Hi-Bred. ®Herculex is a registered trademark of Dow AgroSciences LLC.