Predicting the environmental impact of transgene outcrossing to wild and weedy rices in Asia

Asia is the center of origin of Asian cultivated rice, Oryza sativa, and is also home to numerous wild species of Oryza. Two wild species, O. rufipogon and O. nivara, are abundant in many parts of Asia and are known to hybridize with O. sativa under natural conditions. Numerous types of weedy rice also occur in Asia, derived from O. sativa, wild species, and hybrids between wild rices and O. sativa. Genetic engineering of rice for resistance to insects, diseases, and abiotic stresses has been rapidly advancing, although no transgenic varieties have as yet been widely field tested. We propose an interdisciplinary set of research activities to help predict the consequences of transgene outcrossing to wild and weedy rices, before transgenic varieties with enhanced stress resistance are extensively released into the environment.