Plants engineered for certain characteristics will have major benefits for the global environment. The primary impact will result from a reduction in the overall use of chemicals to protect against plant viruses, which often claim up to 80 percent of many crops. Like vaccines for humans, biotechnology enables breeders to insert small fragments of plant viruses into crops so they develop natural protection or immunity against the disease and pass this trait on to future generations.

Losses of crops to insect pests can be equally devastating. Biotechnology can confer resistance to those pests in specific crops and locations. For example, crops containing insect-resistant genes from Bacillus thuringiensis have made it possible to reduce significantly the amount of pesticide U.S. farmers apply to cotton crops. In the case of cotton alone, the National Research Council reported a reduction of 5 million acre-treatments, or about 1 million kilograms of insecticides, in 1999 compared with 1998 (NRC, 2000). Even though chemicals and their precision application have been greatly improved in the last two decades, residues continue to enter the soil and are washed into watersheds. Biotechnology may offer our best hope for significantly reducing this chemical stress to the environment.

From my perspective as an agricultural engineer whose career has focused on water and soil, the potential impact of biotechnology on the preservation of land resources would be significant. When crops are genetically engineered to resist herbicides, pests, or diseases, farmers can reduce activities that disturb the land. For example, techniques such as weeding require moving the soil, which results in erosion. Engineered crops will make it more likely that producers in both developed and developing countries will retain valuable topsoil rather than sending it by the ton down rivers to the sea.

A second tremendous benefit will be higher yields, which might seem like a disadvantage at a time when U.S. producers are being paid historically low prices for their crops. However, this situation has as much to do with government agricultural and trade policies as with crop yields. Consider the global situation. One of the major technologies that led to the Green Revolution in the 1950s and 1960s was the development of high-yield semidwarf varieties of wheat. Back then, it took plant breeders 10 to 12 years of mixing thousands of genes to produce these varieties. Today, breeders can select a specific genetic trait from any plant and move it into the genetic code of another plant, thereby developing new varieties much more quickly. Speed is not just a convenience for the scientific community; it is critical for us all. World population may reach 9 billion by 2050, and all of those people must be fed. Unless crops produced on land now devoted to agriculture can be made more productive, the disappearance of rain forests, wetlands, and other habitats—and the human misery that come with them—will surely accelerate.

Most crops grown in this country produce less than 50 percent of their genetic potential, and crops raised in the developing world yield far less. The



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