Genetically Engineered Pesticides

            Genetically Engineered Pesticides .
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             Genetically engineered pesticides have been created with the purpose of .
             killing insects that destroy crops by the use of microbial pathogens. Plants have .
             also been genetically engineered to produce toxic proteins themselves, without .
             needing pesticides. .
             An example of this is the baculovirus which, like other genetically .
             engineered pesticides, gets a gene inserted into it (by the use of restriction .
             enzymes that splice DNA and allow genes to be added to the sticky ends) .
             that encodes for a toxin specific to the insects it is trying to eliminate which in this .
             case are bollworms and budworms. It uses a toxin found in scorpions and doesn't .
             harm humans or wildlife. The sticky ends base pair with the complementary .
             sticky ends of the scorpion DNA fragment. The fact that viruses and their hosts .
             have such specialized relationships means that it is possible to target specific .
             insects that need to be controlled, while not harming ones that may be beneficial to .
             the crops.
             The scientists conducted the tests on small field plots using the procedures .
             of the Environmental Protection Agency. The growth of the cotton plants used .
             surpassed or at least was equal to that when using different biological .
             insecticides.
             .
             A problem encountered on the way to this finding was that the virus was .
             taking 5-7 days to kill the insects, and the insects exposed were eating increased .
             amounts before they died. Deleting a gene in the virus solved that dilemma. .
             Strains of the virus that acted faster were found, and toxin genes were inserted that .
             had a toxic affect when expressed. Toxins from different organisms .
             were tested for this position, and the scorpion gene proved the most effective. .
             There were no effects on the innocuous insects that weren't targeted by the .
             pesticide, such as spiders, honey bees, and some insects. Pesticides that are in use .