Establishment Of Plant Regeneration System And The Study Of Polyploidy Induction Of Dendrobium

In this paper we studied micropropagation technology of three Dendrobium orchid systematically, and established a better regeneration system. Colchicines liquid was also used to induce polyploid plants. These methods and data could offer significant referenced datum for the future. The results showed:Growth regulators and media types were not required during the stage of embryo culture. Light conditions and dark environments had little effect on seeds germination, but had great relations with the growth of protocorm bodies. Light was required during embryos formed protocorm bodies, or the protocorm bodies would be dead. In order to improve the survival rate, and reduce pollution rate and mortality during the sterilization treatment, the stems should be sterilized in batches based on their maturity. For the younger stems, with 70% alcohol soaked 30 s, 0.1% mercuric chloride sterilized 6 min.With the stems'maturity increased, mercuric chloride sterilization time should be slightly extended.There were different hormone categories and concentration combination in bud's ability of induction and differentiation, 6-BA5.0mg·L^-1+2,4-D1.5mg·L-1 was good for callus induction, and 6-BA3.0mg·L^-1+NAA0.1 mg·L-1 was profit for bud induction. The optimal media and hormone combination for embryoids and buds multiplication of Dendrobium primulinum was MS+6-BA1.0mg·L^-1+NAA0.1mg·L^-1+10% coconut water. Both of foreign additives coconut water and banana juice could promote Dendrobium subculture proliferation. MS+6-BA0.5mg·L^-1+ NAA1.0mg·L^-1+AC0.5 g·L-1 was optimal for rooting. Activated carbon could improve the rooting rate and the quality.The effects of mutagenesis on different genotype varietied combined with different colchicines liquid treatments. Both of the two Dendrobium materials were suit for soaking with colchicines.Dendrobium was sensitive to colchicines. The suitable concentration of colchicines was from 0.2 mg·L-1 to 0.8 mg·L-1, and the rate of mutangenesis was higher between 0.4 mg·L-1 and 0.6 mg·L-1. External features were observed and cytology characters were identified between normal and mutant plants.The results showed that the difference of external features, the number and size of stomas and guard celles were obvious between normal and mutant plants. Identified the chromosome number, we found that there was mixer-fold phenomenon among mutant plants.