Genetically modified (GM) rice has been developed to introduce and enhance desirable traits, including tolerance to abiotic and biotic stresses, resistance to pests and diseases, and improved quality. However, concerns persist regarding the safety of GM rice for human health and its potential environmental impacts, particularly the risk of gene flow to non-GM and weedy rice populations. Numerous studies on GM crops have reported gene flow events between GM rice and related plants in field conditions. To address these safety concerns, this study investigated pollen-mediated gene flow from resveratrol-enriched GM rice Agb0102 to the non-GM rice cultivar Dongjin and weedy rice R55 over a three-year period. The results revealed an average gene flow frequency of 0.014% from GM rice to non-GM rice and 0.003% from GM rice to weedy rice. Gene flow events were primarily confined to a 1-meter radius, with the highest frequency (0.058%) observed at a distance of 30 cm in the Dongjin pool. This localized gene flow is likely driven by overlapping flowering times and genome compatibility between GM and non-GM rice. Additionally, wind direction and insect-mediated pollination may explain the occurrence of three out-crossing events in the R55 weedy rice pool, with the farthest event detected at a distance of 600 cm. These findings provide valuable insights into the dynamics of gene flow in GM rice cultivation and highlight the need for risk assessment and management strategies to mitigate potential ecological impacts in large-scale field conditions.

Keywords: Genetically modified (GM) rice, Pollen-mediated transfer, Out-crossing, Biosafety