Methods: Hairy root of Isatis indigotica was ob tained from infected cotyledon explants after infection with Agrobacterium rhi zogenes strains A4, R1601 and ATCC15834.

• 方法:分别用发根农杆菌A4，R1601和ATCC15834三种菌株感染菘蓝的子叶外植体，获得毛状根，并筛选了优质株系；