Regeneration System Establishment And Morphogenesis Observation Of Dendrobium Wardianum And D. Loddigesii

In the paper, the utilization values were introduced and present situation of Dendrobium tissue culture in vitro and rapid propagation in home and abroad was reviewed. Based on literature analysis, regeneration system establishment of Dendrobium wardianum Warner. and D. loddigesii Rofle. and their morphogenesis observation was conducted in the current study. The main results were showed as follows:①The best way of sterilizing for lateral buds was: immersing in the 75 percent of the alcohol for 30s, rinsing 2-3 times with sterilized water, disinfecting in 0.1% mercuric chloride solution for 8-10min, rinsing 4-5 times with sterilized water.②For D. wardianum, the suitable culture medium for seed germination was MS + 6-BA(0.5-1.0)mg/L+NAA 0.1mg/L or N6 +6-BA (2.0-3.0 mg/L)+NAA 0.4 mg/L and the suitable culture medium for adventitious buds induction from rhizomes was MS or N6 + 6-BA 4.0mg/L + NAA 0.5mg/L and for shoots proliferation was 1/2MS+ 6-BA 3.0mg/L + NAA 0.1mg/L. For D. loddigesii the suitable culture media for adventitious bud induction and shoot proliferation were MS or 1/2 MS + 6-BA 3.0 mg/L + NAA 0.3 or 0.4 mg/L, as well as MS + 6-BA 6.0mg/L + NAA 0.2mg/L.③For D. wardianum , the optimal culture medium for PLBs induction was MS+6-BA1.0mg/L +NAA0.5mg/L +TDZ0.025mg/L +CH1g/L+CM10 % (v/v) or MS + 6-BA 0.5mg/L + NAA0.5 mg/L+ KT 2.0 mg/L + CH 1g/L + CM 10%(v/v).④For D. wardianum,the optimal culture medium for callus induction was 1/2MS+ 6-BA1.0mg/L+ 2,4-D2.0 mg/L,and for D. loddigesii the suitable culture medium of callus induction from rhizomes was 1/2MS + 6-BA 1.0mg/L + 2,4-D 0.5 mg/L.The axenic plantlet of D. wardianum Warner. can be used to induce callus. In the experiment, only the infancy organizations can be induced to callus, because mature stems and leaves are difficulty to be dedifferentiation. The similar results can be gained in D. loddigesii.⑤There are two ways, direct and indirect , for Dendrobium regeneration. By a direct way, vitro plantlets develop into buds and then produce roots; By a indirect way, vitro plantlets differntiate into PLBs or callus and then produce buds. The shape change process of PLBs and callus was studied through histological method. It was demonstrated that two kinds of callus, namely embryonic callus and non-embryonic callus, can be found in our experiment. The marginal cells of non-embryonic callus can gradually transform into embryonic callus, two forms often occur simultaneously there. Embryo cells can be directly generated from embryo callus. The somatic embryos join the embryonic callus through suspensor. After formed PLBs, they were easily falling down from the embryonic callus.