Studies On Propagation Technology Of Ulmus Pumila ‘Zhonghua Jinye’

Ulmus pumila ’Zhonghua Jinye’,( Ulmaceae Ulmu) is a natural golden leaf mutant of Ulmus pumila. There is a high ornamental value for its golden yellow leaves, bright color, and obvious veins. Because it could be trimmed to various shape for its much branches and full crown, it played an important role on landscape. This paper established the system of propagation technology of cutting propagation and tissue culture of Ulmus pumila ‘Zhonghua Jinye’. The factors that effected cutting propagation and tissue culture were optimized.The main results showed as follows:1 Studies on cutting propagation technology of Ulmus pumila ’Zhonghua Jinye’ were carried out. Using hardwood and softwood cuttings as meterials, it was found that the cuttage survival rate of Ulmus pumila ’Zhonghua Jinye’ was very low and the survival rate of hardwood cuttings was better that of softwood cuttings. The cuttings were treated for different times with different concentrations of IBA, NAA and rooting powder. The results indicated that the hardwood cuttings treated by IBA(100mg/L) and soaked for 1 hour yielded the highest survival rate, which was about 37.5%.2. Establishedt the system of tissue culture and rapid propagation of Ulmus pumila ’Zhonghua Jinye’. MS and WPM medium were used as basic medium and the results showed that MS medium was suitable for Ulmus pumila ’Zhonghua Jinye’. Using stems without bud as explants, the most suitable medium for primary culture was MA+6-BA 1.0 mg/L+IBA0.1 mg/L + 30 g/L sucrose on which explants germinated well. The shoots come from primary culture were inoculated on subculture medium with different plant growth regulators. The results showed that the optimal subculture medium was MS medium supplemented with 6-BA 0.1 mg/L+IBA0.01 mg/L + 30 g/L sucrose, the proliferation coefficient of 5.59, and the shoots grew well.3. Established the organogenesis regeneration system of adventitious buds of Ulmus pumila ’Zhonghua Jinye’. Mature seeds were used as material to obtain sterile seedlings. Then the tender tip of sterile seedlings were used as explants to induce callus. The best callus induced medium was MS + 6-BA 0.1 mg/L+NAA0.5mg/L+ 30 g/L sucrose, on which the callus rate was 68.5% and the callus grew well. The optimal adventitious bud differentiation medium was MS + 6-BA 2.0mg/L + NAA 0.5 mg/L + 30 g/L sucrose, adventitious bud regeneration rate of 65.0%, on which the adventitious buds elongated well and developed to complete plant.4. The optimal rooting medium was 1/2MS + IBA 0.1 mg/L + 30 g/L sucrose and the rooting rate is 63.3% and the average number of root was 2.5. After domestication, the survival rate of the seedlings was 80%.