发根土壤杆菌(Agrobacterium rhizogenes)在芸薹属作物上的高效遗传转化

利用发根土壤杆菌(Agrobacterium rhizogenes)在甘蓝、花椰菜、抱子甘蓝和油菜的下胚轴切段上进行遗传转化。在这些植物基因型中,花椰菜的转化培养获得了最高的根诱导频率,而甘蓝的转化培养得到了最高的转化频率。同菌株LBA9365和LBA8490相比,发根土壤杆菌LBA9402诱导的根数较多。沿着下胚轴依次截取切段进行转化培养,结果发现从子叶下切段到根系上面的切段,其根诱导频率呈阶梯状上升趋势。在切段上的单根转移培养之前,截取下胚轴切段(此切段仍保留有所有的根)上1～2mm长的顶端部分,转移到固体培养基上培养,结果大大提高了转化频率。

High Transformation Freqtuncy of Brassica Crops with Agrobacterium rhizogenes

Genetic transformation by Agrobacterium rhizogenes was carried out using hypocotyl segments of cabbage, cauliflower, Brussels sprouts and oilseed rape. Among these plant genotypes, cauliflower exhibited the highest root induction frequency whereas cabbage showed the highest transformation frequency. Bacterial strain LBA 9402 induced more roots than strains LBA 9365 and LBA 8490. The culture of sequential segments along the full length of the hypocotyl showed that there was a gradient of increasing root induction frequency from cotyledons to the root.Transformation frequency was remarkably raised when 1-2 mm top parts of segments with all roots still attached were transferred onto the solid medium before individual roots on segments were transferred.