Progress 11/02/02 to 10/31/07
Outputs
Progress Report Objectives (from AD-416) 1)Characterize PRSV isolates in Bangladesh, 2)engineer coat protein transgene constructs of representative PRSV isolates from Bangladesh, 3) develop transgenic papaya with the PRSV transgene constructs and identify R0 lines that are resistant to PRSV, 4)evaluate progenies of R0 plants for resistance and horticultural characteristics, and select promising lines for advanced testing, 5)obtain regulatory and intellectual property rights approval for selected lines, and 6)increase the seeds of selected transgenic papaya lines or cultivars and subsequently release seeds to farmers and households. Approach (from AD-416) Viral strains will be collected, sequenced, and engineered for insertion into papaya via biolistic transformation. Other transgene constructs will be engineered with segments of coat proteins and synthetic genes; previous work showed that these constructs confer resistance. At the start of the grant, work will be done to satisfy all intellectual property, regulatory, and biosafety requirements that are needed to transfer transgenic papaya to Bangladesh. These efforts will be done by collaboration between Cornell, ARS, and Bangladesh personnel. Transgenic R0 plants that are resistant to PRSV strains in Bangladesh will be transported from Hawaii to Bangladesh. We will collaborate with scientists from Bangladesh to test the transgenic plant in Bangladesh, and work through necessary steps to have the selected lines deregulated so seeds of these lines can be released to poor farmers and households. All of the activities in Bangladesh will be done in close collaboration with personnel in Bangladesh so there will be governmental and public awareness on the development, testing, and release of the transgenic papaya. We hope that this project will serve as a model on how to effectively transfer biotechnology to developing countries in a timely manner. Documents Trust with CIMMYT. Log 22981. Formerly 5320-21000-008- 03T (11/04). Formerly 5320-21000-010-03T (06/06). Significant Activities that Support Special Target Populations This report serves to document research conducted under a Trust agreement between ARS and CIMMYT. Additional details can be found in the report for the parent project 5320-21000-011-00D, Molecular Resources for the Improvement of Tropical Crops. During the progress period of the last report, a petition was submitted to the Bangladesh Agricultural Research Institute to import and do confined field testing of the transgenic lines that we had developed for Hawaii. The petition was not approved by the Bangladesh authorities so steps to import and test the transgenic papaya lines in Bangladesh could not be taken. In the mean time, through an SCA the potential transgenic lines were tested against a new set of PRSV strains at Cornell with collaborator Dr. Marc Fuchs. Three strains from the potential sites for field trials in Bangladesh were tested against transgenic lines. One strain (S3) collected from Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU) incited mild symptoms and showed delay in infection of transgenic plants. Thus, if approval had been obtained for import and testing of the transgenic lines, we would have chosen the BSMRAU site for testing. Twenty six transgenic papaya lines with the synthetic gene were identified and are being propagated in tissue culture. The project is monitored through email and telephone communications, meetings, and progress reporting. The following are publications produced: Gonsalves, D. 2006. Transgenic Papaya: Development, Release, Impact, and Challenges. Advances in Virus Research. 67:317-354. Gonsalves, D., Vegas, A., Prasartsee, V., Drew, R., Suzuki, J., Tripathi, S. 2006. Developing Papaya to Control Papaya Ringspot Virus by Transgenic Resistance, Intergeneric Hybridization, and Tolerance Breeding. Plant Breeding Reviews. 26:35-781.
Impacts
(N/A)
Publications
|
Progress 10/01/04 to 09/30/05
Outputs
4d Progress report. This report serves to document research conducted under a trust agreement between ARS and International Maize and Wheat Improvement Center (CIMMYT). Additional details of research can be found in the report for the parent CRIS 5320-21000-010-00D, Genomic and Biotechnological Approaches for Evaluating and Improving Tropical Crops. A Bangladesh scientist completed his stay at our ARS laboratory and was able to write a detailed analysis of papaya and papaya ringspot virus in Bangladesh. To determine the sequence variability of papaya ringspot virus isolates in Bangladesh, surveys and collection of virus isolates were carried out in 2004. Papaya ringspot virus isolates were sent to our ARS laboratories for sequence analyses of their coat protein genes. The coat protein genes were isolated using RT-PCR and sequenced. All isolates showed high similarity in coat protein sequences, and remarkably, also showed high similarity to the coat protein
sequences of papaya ringspot virus isolates from Hawaii. The similarity with Hawaii isolates suggests that our transgenic papaya with segmented genes that show resistance to Hawaii isolates may be resistant to the Bangladesh isolates. If so, we could these lines initial introductions and trials in Bangladesh. This would speed up the progress towards our goal of developing and using transgenic papaya to help the rural households in Bangladesh.
Impacts
(N/A)
Publications
|