In order for the transgenic PRSV papaya to be commercialized, it has to undergo risk assessment analyses required by the regulatory agencies in the country. There are four levels of biosafety assessment in the Philippines: (1) contained research in laboratories and screenhouses, (2) small field trials, (3) large field trials and (4) commercial release. Assessments are guided by the Philippine Biosafety Guidelines formulated by the National Committee on Biosafety of the Philippines (NCBP)
After five years of research, the transgenic PRSV-resistant papaya project of the Philippines is now in its second phase (small field trials). During the first phase, transgenic lines were obtained in the lab and the highly resistant first generation of transformed plants is now at the fruit bearing stage. So far, efficacy has been convincingly demonstrated in a contained environment, but efficacy under Philippine field conditions remains to be shown.
A small-scale field trial will be conducted within the 200 hectare experimental area of the Institute of Plant Breeding in UPLB. An isolated (fenced) field will be established to conform to the requirements of the regulatory agency. Based on the data gathered from the small-scale field trial, the best lines in terms of resistance to PRSV and agronomic performance will be selected for subsequent multi-location field trials.
In addition to the field testing, new transgenic products will be developed to maximize the use of the transgenic PRSV-resistant sources. Selected second-generation transgenic lines will be backcrossed to either parent of the popular IPB-bred hybrid cultivar Sinta and the high papain variety, red Solo.
A regulatory package addressing the requirements of Philippine regulations on the release of transgenic crops will be developed for the transgenic papaya product. While current regulations may opt to consider relevant regulatory data generated in other countries, it is expected that most of the data, particularly for the environmental safety assessment, will be generated within the country. These will include data on molecular characterization of the selected event(s), effects on non-target organisms, gene flow, nutritional analysis and some limited feeding studies. Since transgenic papaya with PRSV-CP technology has already been commercialized in other countries, the regulatory package developed for them will serve as guide.