Investigation On Colchicine Induced Polyploidy In Phaius Tankervilleae

Phaius tankervilleae, a perennial herb, belongs to the Phaius Lour of Orchidaceae family. It has graceful flower, long oval-shaped lanceolate leaves, bright color. It is one of the most famous wild tropical orchids. The short periods of flowering and intergeneric sterility are the major barriers for large-scale popularization and utilization of Phaius tankervilleae. Recent studies suggested that polyploid breeding is a useful way to create new genetic species. Therefore, chromosomal polyploidization of Phaius tankervilleae could be powerful way to overcome breeding barriers in the specie. In this study, we used colchicine to induce polyploization in tissue culture of Phaius tankervilleae, studied the isolation of chimera from the cultures. Herein, brief results are as follows:1. Constructed the in vitro one-step plantlet regeneration method of Phaius tankervilleae. Using pesudobulbs and stem tips of seedlings as explant, we successfully induced the generation of PLB on Hyponex No.1+2.0mg/L BA+2.0mg/LNAA+coconut water100ml/L+active carbon2g/L+agar8g/L+sucrose20g/L. Rooting medium culture is not needed after the induction, and the rooting rate of regenerated plants is100%, survival rate of translation is about98.3%. Our date showed that the method could reduce tissue culture pollution, and the procedure was simplified, cost saving, shorten the production cycle.2. Constructed the in vitro polyploid inducing method of Phaius tankervilleae. An optimal result can be obtained by immersing protocorm into0.02%colchicine for6days with a mutation rate of22.5%. There were3pure tetraploid and107are chimera, which increased specie resources and provided reference for polyploid induction of Orchidaceous plants. Pure tetraploid shows stout, leaves hypertrophy, slow growth.3. Constructed suitable isolation and purification method of Phaius tankervilleae chimera. Inoculate the chimera plant with its root and cut out on one-step seedling formation medium. Induce PLB and develop into plantlets, and then2pure tetraploid was obtained. The separation of chimeric improves the efficiency of polyploid induction.