They also assert that using "Roundup Ready" crops and Roundup in combination increases crop yields by five percent, which also benefits the farmer through increased profits (Sale 17). A reduction in the need for pesticides is another benefit of genetic engineering that is often cited. Robert Shapiro, the CEO of Monsanto, explains this theory in the magazine article "How Genetic Engineering Will Save Our Planet." Ninety percent of the costly chemicals sprayed on crops are wasted, which is not good for the environment, or for the farmer who is paying for them. But by using biotech, plants can be genetically coded to resist or kill insects and pests by themselves, without using chemical pesticides. The genetic technology is also more efficient than chemicals, which take a large amount of raw materials and energy to produce and apply (Shapiro 29). Bt, a pesticide that naturally occurs in the environment, has also been incorporated in genetically modified (GM) crops. Crops such as corn and soybeans have been engineered to produce the Bt substance by themselves, using a gene from the Bt gene code. This allows the plant to defend itself from pests by manufacturing its own natural pesticide. One statistic shows that Arizona farmers who use Bt corn have reduced their usage of chemical insecticides by 75 percent (Nash 46). GM crop advocates cite these types of statistics as proof that genetic engineering in agriculture will benefit the