Molecular and Genetic Approach to Develop Sexing Strains for Field Application in Fruit Fly SIT Programmes


To optimize the application of existing medfly strains in their genetic composition, productivity and application; to advance the development of third generation strains using nuclear and molecular methods; and to initiate the development of sexing systems in other fruit fly species.


The selection of the best medfly sexing strains available and their large-scale use has considerable operational and economic implications. It is essential that optimal procedures are developed to maximize the sexing strain productivity and efficiency; that the potential for strain deployment under different field conditions and geographical locations is assessed and that the isolation and evaluation of improved sexing genes are examined. Basic genetic and cytogenetic studies are being carried out on several fruit flies of economic importance, such as Ceratitis capitata, Bactrocera tryoni, Bactrocera phillipinensis and Bactrocera cucurbitae. These studies provide the essential tools for the development of sexing strains and include genetic mapping, mutation induction and cytology. Improvement of current strains is being pursued by the isolation of chromosome inversions to increase strain stability and by the introduction of improved strain management practices in mass rearing facilities. Field and field cage studies are also being carried out with medfly (Ceratitis capitata) genetic sexing strains. In the genomes of the medfly and Bactrocera tryoni searches are underway for genetic elements that might be useful for the synthesis of genetic transformation vectors.


Six contract holders from Argentina, Brazil, Greece, Guatemala, Philippines and Bangladesh; three Agreement holders from Australia, Italy and USA.


  • The final Evaluation Report summarizes achievements under this seven-year CRP (1994-2001), and shows the list of publications prepared during the CRP by participating researches.
  • The Final Proceedings[pdf] of this CRP were published in a special issue of the journal GENETICA, and include an additional collection of 13 peer-reviewed scientific publications.