Studies on the Vegetative Propagation Techniques of Glyptostrobus Pensilis (Lamb.) K.Koch
|School||Nanjing Forestry University|
|Keywords||Glyptostrobus pensilis (Lamb.) K.Koch Tissue Culture Plantlet Regeneration Hardwood cutting Minicutting|
Glyptostrobus pensilis （Lamb.） K.Koch was an endemic and endangered species in China, therefore, it is great significance to study on the vegetative propagation techniques of Glyptostrobus pensilis （Lamb.） K.Koch. In this paper we developed techniques on tissue culture and cutting propagation of Glyptostrobus pensilis （Lamb.） K.Koch. The results were as follows.Stem explants excised from 100-day-old in vitro seedlings and one-year-old trees for axillary buds. Green axillary buds were induced in the medium without hormone or with low concentration of hormone. Under the optimized condition for stem explants excising from sterile seedling, in 20 and 35 days green axillary buds were induced on the MS medium containing of 0.5mg·L-1 ZT ,5.0 mg·L-1VC and 0.3% sucrose. Average bud number could reach. 4.19 and the proliferation coefficient 3.965. Efficient shoot elongation was achieved by transferring the clusters of axillary shoots to MS medium containing 0.1 mg·L-1 GA3,5.0 mg·L- 1VC and 0.3% sucrose. The elongated axillary shoots were rooted at a rate of 58.3% on half-strength MS medium with 0.5 mg·L-1α-naphthalene acetic acid （NAA）,5.0 mg·L-1VC and 0.1% sucrose in 2 month.The optimized condition for stem explants excising from one-year-old tree was under the DCR medium containing of 5.0 mg·L-1 VC and 3% sucrose and green axillary buds were induced in one months. Average bud number could reach 2.368 and proliferation coefficient 1.956. Efficient shoot elongation was achieved by transferring the clusters of axillary buds to MS medium. The elongated axillary buds were rooted at a rate of 26.6% on minicutting.The cuttage propagation techniques of Glyptostrobus pensilis （Lamb.） K.Koch was also explored in this study by testing various factors including ages of the mother tree, cutting position, medium, treatments of hormone types, concentrations and duration. The best way for cottage of Glyptostrobus pensilis was that cuttings came from the top part of 1 or 2-years-old ortets, cuttings soaked in IBA 2000ppm solution for 30s or in NAA 100ppm solution for 2h before inserting in the medium with combination of pearlite:peat =3:7, the rooting ratio of cutting under these treatments above could reach 85%. Significant differences of rooting ratio were found existing among genotypes, indicating that it was effective to select the individual plant with easily rooting ability.