转基因水稻与野生稻(Oryza nivara Sharma et Shastry)杂交后代种子萌发率转基因水稻与野生稻(Oryza nivara Sharma et Shastry)杂交后代种子萌发率

Seed dormancy, which is an important adaptive characteristic for wild plant species, can be determined by germination tests. The presence of seed dormancy is generally considered a primitive trait of common wild rice (Oryza nivara and O. rufipogon) in comparison with cultivated rice (O. sativa). Seed dormancy of hybrids between transgenic rice and wild rice can be therefore of importance for assessing the possibility of transgene persistence in wild populations after it escaped through crop-to-wild gene flow. Seed germinations were compared between the F3 and F4 generation progenies of hybrid between an insect-resistant transgenic rice line (CpTI rice) and annual common wild rice (O. nivara) under four different treatments. The results showed that the transgenic hybrid seeds presented relatively strong dormancy, the seed viability and dormancy were not significantly associated with transgene, and the degree of seed dormancy in progenies would decline from one generation to the next. This result suggests the possibilities of transgene persistence and spread in the wild populations after transgene escape, although the possibilities might decline from generation to generation.