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Introduction

In the 1930's, crop yields in the United States, England, India, and Argentina were essentially the same. Since that time, researchers, scientists, and a host of federal policies have helped U.S farmers dramatically increase yields of corn, wheat, soybeans, cotton, and most other major commodities. today fewer farmers feed more people than ever before. This success, however, has not come without costs. (National Research Council) The U.S. Environmental Protection Agency (EPA) has identified agriculture at the largest nonpoint source of surface water pollution. Pesticides and nitrate from fertilizers are detected in the groundwater in many agricultural regions. Soil erosion has become a major concern in many states; pest resistance to pesticides continues to grow, and the problem of pesticide residues in food has yet to be resolved. The explosion of technology and the green revolution have incredibly increased the production of food in the United States, but today we need to combine "technology" with "traditional" for a more sustainable system that will preserve the environment, reduce the pest population, and reduce the costs of inputs.

Pest-i-cide = pest killer What is a pest?

A pest is simply any living organism whose presence conflicts with the interests of people. There are literally thousands of insects, weed, plant disease and other species that conflict with U.S. crop production activities. These pests cause crop losses by consuming, infecting, weakening, competing with or otherwise reducing the value of the crop being produced.
What is a pesticide? Since 1945, vast fields planted with only one crop or a few crops, as well as home gardens and lawns, have been blanketed with a variety of chemicals called pesticides (or biocides) to kill organisms that humans consider to be undesirable. The main pesticides include insecticides (insects killer), herbicides (weed killer), rodenticides (rodents such as mice and rats), fungicides (fungi). Pesticides can improve crop yields and help control populations of disease organisms. However, there is considerable evidence that the wide spread use of pesticides can have harmful effects on wildlife, ecosystem structure and function, and human health. Over the past 200 years, an increase number of insects and other pests have become serious threats to crops. The major reason for this is because large areas of diverse ecosystems containing diverse species, have been replaced by simplified agricultural ecosystems containing only a large population of one or two plant species. In such simplified ecosystems pests are more likely to develop. As a result, people have had to use pesticides. The ideal pest-killing chemical would kill only the target pest without any short or long-term health effects on nontarget organisms, including human beings; would broke down into harmless chemicals in a relatively short time, would not cause target organisms to acquire genetic resistance to its effects. Unfortunately, no known pest control method meets all these criteria. Before 1940 there were only a few dozen pesticides on the market. Many of these pesticides were nonpersistant organic compounds, made or extracted from natural plants. Those were called first generation pesticides; an example would be caffeine, which is an excellent insecticide that can be used to control tobacco horn worms, meal worms, milkweed bugs, and mosquito larvae. A second type of first generation pesticides in use before 1940 consisted of persistent inorganic compounds, made from toxic metals such as arsenic and mercury. Most of these compounds are no longer used because they are highly toxic to people and to animals, they contaminate the soil for 100 years or more, and they tend to accumulate in soils to the point of inhibiting plant growth. A major revolution in insect pest control occurred in 1939 with the synthetic organic chemicals such as DDT (dichlorodiphenyltrichloro-ethane). Those are known as second generation pesticides. DDT and other related second generation pesticides have been widely used because they are easy and cheap to produce, and they kill many types of pest organisms over a long period of time.

In 1972, DDT and other related pesticides were banned in the United States. DDT and other fat-soluble pesticides can be biologically amplified in food chains and webs to levels hundreds to millions of times higher than those in the soil or water. Because of biological amplification, all people born after 1950 have carried several parts per million of DDT in their fatty tissues, with unknown long-term harmful effects. (The movement and biological amplification of DDT in the biosphere.)

Year	# Resistant Species
1945	15
1950	20
1955	25
1960	150
1965	200
1970	300
1975	350
1980	400
1986	462

Pesticide regulation in the United States In 1972, Congress passed the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). This act requires that all commercially available pesticides be registered with the Environmental Protection Agency (EPA pesticide regulations).

Page by Meriem ElHadj & Scott Tschetter

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