It is possible to create effective, natural insecticides from these substances to protect crops that, unlike wild plants, may have lost their capability through cultivation to cope with pests. Neem trees produce oil that alters the hormones of bugs so that they cannot fly, breed or eat (National Academy of Sciences 1992). For example, the Douglas fir has a special sap that wards off beetles if it is attacked. Many plant species produce substances that protect them by killing or repelling the insects that feed on them. Organophosphates designed to affect the brain and nervous system of insects, sometimes damage those of humans and animals. It was only later that the degree to which these pesticides remain in the environment was discovered (Carson). When farmers used pesticides such as DDT and malathion, there was little understanding of how dangerous and long-lasting these chemicals are. Mass production farms rely on synthetic pesticides, however, because they are cheaper than organic ones. Many farmers will not use synthetic pesticides, and some consumers will only buy organic produce. Older pesticides such as DDT killed bald eagles, birds, fish and even people (Carson). They penetrate to groundwater, pollute streams and harm wildlife, including natural predators of the targeted pests. Almost 98 percent of sprayed pesticides do not reach their targets. This "pesticide drift" occurs when pesticide dust and spray travel by wind to places unexposed to pesticides. Humans come in contact with dangerous pesticides on food, in water and in the air near farms. However, they pose serious threats to the environment and to people. Synthetic insecticides such as organophosphates are important, effective tools in modern crop management. BackgroundĪgricultural crops are under constant assault by insect pests, making insecticides essential to reduce losses. Which begs the question: Do we want organic produce or plentiful produce? This question inspired my science project theme: Can insecticides be created out of natural substances? Organic, plant-based pesticides that rely on plants' natural defenses against insects may not only be effective and inexpensive for protecting crops, but also safer and more environmentally friendly. However, the killers we cannot evade are insects. We weed-whack, fence, and cover our plants to keep them from rabbits and deer. By Kalia, Grade 8, New York, 2011 YNA Winner IntroductionĮvery year my family and I wage a constant war for homegrown fruits and vegetables.
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