Abstract:

To determine the best NAA/6BA ratio for shoot tip culture of different varieties of sweet potato, we set up NAA/6BA ratio at 3 concentrations (0.1 mg/L/2.5 mg/L, 0.2 mg/L/2.5 mg/L, 0.2 mg/L/1.0 mg/L), and studied the effects of different hormone treatments on the shoot tip culture seedling rate, callus diameter, adventitious root number, leaf number and plant height of ‘Beijing 553’, ‘Hongxiangjiao’, ‘Sushu 8’, ‘Yanshu 25’, ‘Anjiyu’, ‘Jixu 23’, ‘Yuzi 7’, ‘Shangshu 19’, at the same time, investigated the transplant survival rate of test-tube plantlets of different varieties. The results showed that: the culture efficiency of ‘Hongxiangjiao’, ‘Jixu 23’, ‘Yuzi 7’ and ‘Shangshu 19’ was the highest under the treatment of 0.1 mg/L/2.5 mg/L, that of ‘Anjiyu’ was the highest under the treatment of 0.2 mg/L/2.5 mg/L, and that of ‘Sushu 8’, ‘Beijing 553’ and ‘Yanshu 25’ was the highest under the treatment of 0.2 mg/L/1.0 mg/L. In the process of shoot tip culture of sweet potatoes, there are significant differences of the appropriate ratio of NAA/6BA among different varieties, and the dosage and proportion of hormones should be adjusted according to the characteristics of the varieties in practical production.

Key words: sweet potato, NAA/6BA ratio, shoot tip culture, test-tube plantlets, seedling rate, cultivation efficiency