Since the widespread adoption of so-called biotech, or genetically modified/engineered (GM/GE), crops by many large U.S. farms a decade and a half ago, U.S. farmers and scientists have been conducting one, large-scale, agricultural experiment.
This experiment–mostly involving corn, soy and cotton–has raised several concerns (e.g., the spread of GM genes to other plant populations) both here and abroad. The two main concerns with biotech crops are the environmental impact(s), and, the economic costs/benefits. In Europe, food safety is also a major concern.
But according to a new report from the National Research Council (NRC), the research arm of the National Academies, the U.S. agricultural industry’s shift to genetically modified crops has proven to be mostly beneficial–both economically and environmentally.
The National Research Council reports that the use of genetically engineered crops results in less harm to wild life, less soil erosion, and greater cost savings. Its findings could impact agricultural practices in other nations.
Numerous studies on biotech crop usage over the years have added fuel to the debate over their value and safety. Different studies showed different impacts and benefits depending upon the type of crop being grown, the location of the farm, and other factors such as whether the local environment was conducive to pests (insects, fungi, weeds, etc.). Also, agricultural practices vary across the country, with some farmers still plowing and tilling after each harvest.
But according to the NRC, most of the impacts from genetically engineered crops are relatively clear. For example, farmers often have to spray large quantities of dangerous insecticides on their crops to control these damaging pests. But, through utilizing a GM crop strain modified to contains a bacterial toxin gene that kills insects, much less harmful insecticide needs to be sprayed. Thus, this biotech benefit saves wildlife and farming costs.
One of the biggest environmental benefits from biotech crops has been controlling soil erosion (which also releases carbon into the atmosphere). To control weed-spreading, farmers would plow/till their fields regularly. With biotech crops that are able to tolerate herbicides, such as with soy, farmers simply spray their crops (the most common herbicide nowadays is glyphosate, a much less toxic herbicide) one or two times. This saves a large amount of fuel and significantly reduces soil erosion.
The NRC report did caution that these benefits are not certain over the long-term. The threat from weed or insect resistance–such as to the bacterial gene toxin–is always a possibility, rendering such genetically modified crops ineffective and forcing farmers to return to the far more toxic chemicals of the past.
This scenario could be avoided through the development of different crop varieties to thwart resistance, or by using more than one chemical (though this raises new concerns over soil and crop contamination and food safety).
One newer practice being advocated is the planting of “refuge” crop zones adjacent to the GM crops. These refuge crops are not engineered and provide an attractive food source for would-be pests, which, not being exposed to the biotech crop, would not develop resistance. This in turn would create a population of insect pests that would counter-balance, or keep in check (through mating) any resistance genes that might emerge in the biotech-feeding pest population.
The evolution of resistance in insects and other pests is the subject of a great deal of current research and much remains unknown about the evolution of acquired resistance and how this spreads through a population.
One other factor here is preserving competition and innovation amongst industry players. Mergers of agri-businesses tend to lead to a more monolithic, more limited research culture (due to cost control interests). Currently, the U.S. Dept. of Justice is looking into this issue.
While still controversial, biotech crops that grow under dry/poor soil conditions and resist insect predation hold great promise to developing nations and societies where drought and damaging pests are common.