Why can’t the desired traits – like drought- or stress-tolerance or improved-yield traits – simply be achieved through conventional breeding?
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Q: Why can't the desired traits – like drought- or stress-tolerance or improved-yield traits – simply be achieved through conventional breeding?
A: No matter where they are farmed in the world, crops are routinely challenged by a number of agronomic and environmental factors. Some of these factors include insects, disease and weather. We believe breeding can play a key role in meeting some of these challenges.
Plant breeding programs are typically structured to test new products over a number of locations and years before the product is ultimately commercialized for farmers. This testing regime enables plant breeders to select for a number of various stresses including drought, and to select for increased yield. Conventional selection for these types of traits is very difficult because of the genetic complexity presented by these types of traits.
As a result, some of these factors may only be addressed and/or could be addressed more comprehensively through plant biotechnology. Today, biotechnology is commonly used in crops to significantly accelerate the progress plant breeders are able to achieve by identifying, enhancing and deploying key genes addressing these productivity issues.
One example of the application of both breeding and biotechnology can be found in corn research. For years, plant breeders and researchers worked to combat a devastating insect that limited the harvestable output of corn on-farm. The insect, called the European Corn Borer, bores its way into a corn stalk and carves out the middle of the stalk, severely damaging the plant. The insect damage results in lower grain yields and/or in the corn plant falling to the ground, making the grain difficult to harvest.
Farmers and plant breeders tried to combat this pest with control methods such as plant breeding and insecticide applications. Plant breeders were never able to deliver a breeding approach that could consistently deploy resistance to this insect across a broad range of hybrids in order to thoroughly combat the pest or stop it from ruining corn yields, season after season.
Insecticide sprays were also routinely applied to control this pest. However, to be effective, insecticides must come in contact with the corn borer. One drawback of this approach was the insect was often able to bore inside the plant before or after the insecticide application, resulting in marginal control of the pest and corn yield losses.
Ultimately, plant biotechnology research proved to be the best on-farm approach to combating the pest. The technology, also known as Bt corn, provided farmers with an in-seed and in-plant approach to combating the insect and protecting their harvest. The ‘Bt’ name comes from the source of the insect control gene, Bacillus thuringiensis, a common soil bacterium that has been used for decades by organic farmers. Today, farmers around the world use the Bt corn technology to protect on-farm yields on more than 22 million hectares, or more than 50 million acres, annually.