Several biopesticides are in use today. Biopesticide products are based on natural agents such as microorganisms and fatty acid compounds. They are toxic to targeted pests (such as the European corn borer) and do not harm humans, animals, fish, birds or beneficial resistance to conventional pesticides. One of the most common microorganisms used in biologically based pesticides is the Bacillus thuringiensis, or Bt, bacterium. Several of the proteins the Bt bacterium products are lethal to individual species of insects. Using Bt bacteria in pesticide formulations can eliminate target insects without relying on chemically based pesticides. It is also possible to use pheromones in pest control. Pheromones are naturally occuring substances that insects produce to attact mates. In pest control, pheromones are used to attract insects away from crop plants. For example, pheromone-based traps were used to control fruit fly infestations in california. The European corn borer, one of the most prevelant pests, costs the united states $1.2 billion crop damage each year.
Using biotechnology, it is possible to make crop plants tolerant of specific herbicides. When the herbicide is sprayed, it will kill the weeds but have no effect on the crop plants. This lets farmers reduce the number of times herbicides have to be applied and reduces the cost of producing crops and damage to the environment.
The contributions of biotechnology to the practice of medicine through the discovery and development of a number of potent antibacterial antibiotics is widely recognized. A major effort concerned with the discovery of new structures with antibacterial activities and the chemical modification of existing natural products is still ongoing. Although these antibiotics have found widespread use as growth promoters in the animal health area, only more recently were microbial products produced primarily for animal growth or agricultural purposes, for instance monensin as a coccidiostat for poultry and a growth permittant for ruminant animals. Bacteria, fungi and virus are the most commonly researched as potential microbial biocides. The development of low cost production methods and successful formulation of products such as microbial insecticides represents the commercial cutting edge of biotechnology.
The term insecticide usually bring thoughts of poisonous, non-selective, energy-consuming chemicals that are used to kill pest insects. However, not all insecticides fit this generally accepted stereotype. Those microorganisms which often suppress and naturally control populations or pests which injure man and causes extensive damage to food and fibre crops. Formulation of living viruses, bacteria, fungi and protozoa are called microbial insecticides.
Revolutionary techniques in biotechnology offer tantilizing new prospects for the future. Biological control has a long history, reaching into the undated past when the chinease used Pharoah's ants to control pests of stored gain. Others date the start of biological control to the domestication of the cat. The introduction of an exotic species to control a pest, the classical form of biological control, is claimed to date from 1762 when the indian Mynah was brought to mauritius to control the Red Locust. Subsequent attempts at introduction ocassionally had unwanted results, the introduction of cats to control rats on Ascension Island in 1815 resulted in the extermination of virtually all the sea birds on the island. Successful control of cotton cushion scale by Australian ladybirds in california in 1888 encouraged practitioners to continue to develop biological pest control by the introduction of exotic enemies.
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