ABSTRACT
In several areas worldwide the Sterile Insect Technique (SIT) is used sucessfully to eradicate or control tephritid fruit flies. Three main reasons account for the increased use of SIT: it is a technique friendly to the environment, it is a species-specific technique and it does not generate problems with insecticide resistance. The most important benefit of genetic sexing is that releasing only males increases the effectiveness of the SIT several fold. Additional benefits of using sexing systems include reductions in program costs. Only the active reagent of the SIT, the male, has to be reared, transported, and released, resulting in reduced production costs. As research found no natural sexually dimorphic trait or mutation in medfly that could be used to separate large numbers of males and females, sexing strains were developed through genetic manipulation. The ‘first and second generation’ genetic sexing strains have certain limitations.
