Entomologist Sotero S. Resilva of the PNRI recently embarked on an expert mission to the Agricultural Research Council in Stellenbosch, South Africa to share his expertise on "Using Pupal Eye Color in Determining the Development of Medfly". The technique will be useful in assessing the optimum time for pupal irradiation, which is a critical factor in effectively rendering sterility in the said insects. The correct timing of irradiation would help achieve the required degree of sterilization without damaging the pupae nor compromising the competitiveness of the sterile flies in the field.

The Western Cape in Africa has highly developed fruit export sector that is, however, facing difficulties because pesticide use has led to environmental problems, pest resistance, and even legal impediments. Non-pesticide techniques, such as biological control, mating disruption and sterile insect technique (SIT), have therefore found its role in pest management increasing. 

Mr. Resilva's ten day mission was implemented through the South African Technical Cooperation project, SAF/5/007, on Expanding the Use of the Sterile Insect Technique Against Fruit Pests in the Western and Northern Cape, which is under the auspices of the International Atomic Energy Agency.