Abstract: Several important factors influencing transformation frequency of rice mediated by Agrobacterium were investigated with six important indica and japonica rice cultivars. For indica rice, CC medium was the best for callus initiation. Supplying 1.0-2.0 mg/L ABA to the medium could improve the quality of the calli. Adding sorbitol to the subculture medium could improve the growing state of the calli and decrease the percentage of browning calli. For japonica rice, NB medium was the best for callus initiation, but the improvement of the calli quality through adding ABA was not obvious. During the period of subculture, adding some sucrose could improve the situation of hygromycin-resistant calli. Furthermore, the transformation frequency was increased when selection pressure was removed in the stage of plantlet differentiation during the whole hygromycin selection period. Using suitable proportion of hormone combination was beneficial for callus differentiation. The efficient Agrobacterium-mediated transformation system was established in several rice cultivars and a lot of useful transgenic plants were obtained.

Key words: rice, callu, hormone, transformation, medium

摘要： 以6个重要的籼稻和粳稻品种为材料，研究了影响农杆菌转化水稻频率的几个重要因素。结果表明，对于籼稻品种而言，CC培养基是愈伤组织的最适诱导培养基；添加1.0~2.0 mg/L ABA能有效地改善愈伤组织的质量；在继代培养基中添加山梨醇能改善愈伤组织的生长状态，降低愈伤组织的褐化。而对于粳稻品种来说，适宜的诱导培养基是NB培养基，添加ABA对愈伤组织的改善效果不明显，对于多次继代的愈伤可以适当增加蔗糖浓度以提高抗性愈伤率。此外，在筛选时期适当加大筛选压力，分化时去掉筛选压力，壮苗时加适当的选择压力，可提高转化率。在分化时，采用适宜的激素配比有利于提高分化率。应用所优化的农杆菌转化系统，获得了一些有价值的转化植株。

关键词: 水稻, 愈伤组织, 激素, 转化, 培养基