The most well developed and widely used genetic biocontrol is the Sterile Insect Technique (SIT). This is an insect control strategy devised in the middle of the 20th century, in which a target species of insect is mass-reared to large numbers and then sterilized using ionizing radiation, which causes a multitude of random chromosomal mutations that lead to infertility. Large numbers of irradiated insects are released into wild populations of the same target species. Preferably only sterilized males are released and when they find and mate with a fertile wild female, the female will produce no viable offspring although her drive to find a mate and reproduce has been satisfied. Regular repeated releases of sterile males over time can result in a reduction of the target population and in some cases its local elimination.
Another example of genetic biocontrol involves the use of a hybrid incompatibility phenomenon wherein mating between two strains of a species results in a reduced number of offspring as compared to mating between individuals of the same strain.
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