Decision on Rhizome Age Class of Dioscorea nipponica and Its Propagation

The experimental observations show that the rhizome age class of Dioscorea nipponica was decided through the roots ring hollow,the most rhizome age class of Dioscorea nipponica were 4 to 5 years old in Wudu district of Longnan city.The results also indicationed that the rhizome age class and chemical treatments have a very significant impact on the roots of Dioscorea nipponica,the survival rate of rhizome was the highest reached 96.33% which 1 year old rhizome,three spores on each section,immersing time was 8 hours in 200 mg/kg rooting powder(ABT)solution.