Gene flow from herbicide resistant genetically modified rice to conventional rice (Oryza sativa L.) cultivars

Rice (Oryza sativa L.) is an important feeding crop in Asia, and utilization of genetically modified (GM) rice is highly demanding. For co-existence of GM rice and non-GM rice, the proper confinement measures should be provided. Thus, we surveyed gene flow from herbicide resistant GM rice to the conventional rice cultivars in the field tests. Gene flow frequency decreased with increasing distance between the pollen donor and recipients and did not exceed more than 1% even at the nearest distance. In single recipient model plot, a maximum gene flow frequency was observed at the shortest distance and hybrid was detected up to 12 m from the pollen donor. The direction of gene was coincided with the dominant wind direction. Gene flow assessment to multiple recipient plots was conducted under the high raining season by chance, and abrupt decline of gene flow frequency and maximum distance were resulted. According to the survey results, current regulation for isolation distance is reasonable for environmental safety or for general crop production. However, we suggest an alternative measure for GM rice cultivation that should be supplemented to overcome the out of estimation and in the environment asking higher security levels.