WHAT’S SO SPECIAL ABOUT OUR PAPAYA?

PEPS faculty and grad students Islam Hamim, Wayne Borth, Josaiah Marquez, James Green, and Mike Melzer recently published a paper on transgenic papaya entitled “Transgene-Mediated Resistance to Papaya Ringspot Virus: Challenges and Solutions.” The authors explain that GM papayas developed in Hawai‘i such as ‘SunUp’ and ‘Rainbow’ have remained resistant to PRSV more than two decades, whereas efforts to create PRSV-resistant transgenic papaya in other countries have often failed over time, demonstrating an initial resistance that was ultimately overcome by the virus. For other cases, resistance was inconsistent. The paper focuses on factors affecting transgenic resistance in papaya and attempts to explain why Hawai‘i papayas’ complete and durable resistance has not been replicated elsewhere.