Filter Rearing System for Sterile Insect Technology

Genetic sexing strains (GSS), which produce only males, are now being used on a large scale for the control of the medfly, Ceratitis capitata using the sterile insect technique (SIT). The use of these strains has had a major impact on the overall efficiency of the technique by increasing significantly the amount of sterility induced in field populations and by reducing operational costs. GSS are based on the use of male linked chromosomal translocations, which make possible the linkage of selectable marker genes to the male sex. Two selectable genes have been incorporated into functional sexing strains specifically, white pupae (wp), which allows males and females to be discriminated based on pupal color, and temperature sensitive lethal (tsl), which allows the females to be killed by an increase in ambient temperature. GSS are not 100% stable due to the occurrence of a low level of genetic recombination between the selectable marker and the translocation breakpoint. This results in...