The Research Of Tissue Culture And Mutagenic Effect Of Two Orchids

The reproductive rate of orchid plants is very low and difficult to flower under natural conditions,study on orchid blossom in vitro is beneficial for deep understanding of flower initiation and development;Tissue culture and mutation breeding can greatly improve the efficiency of mutation to cultivate new varieties.At present there was no study about radiation induced mutation and blossom in vitro on “ba 2”,a variant of Epidendrum.The experimental materials of this research was Dendrobium huoshanness and Epidnedium sp,using TDZ、ZT、2,4-D、PP333、6-BA disposed those two orchid plants plantlets for flowering,Setting different gradients on Epidnedium sp studied the radiation effects of radiation treatment with60 Co radiation source.The results are as follows:The effect of 6-BA on the induction of Dendrobium huoshanness was not obvious;the flower bud induction rate was 31.5% with TDZ 0.5mg/L.The induction rate is less than 10%when the TDZ(0.1mg/L and 0.15mg/L) and more flower buds open as normal.Induction of ZT on Dendrobium,when the concentration of ZT is 1.0mg/L, the induction rate is the highest,higher than 1.0mg/L the induction rate was lower. The effect of PP333 on the induction of Dendrobium is not obvious. Test-tube plantlet appeared dwarfing phenomenon. Each hormone on Epidnedium sp had no flower bud.1/2MS is the most suitable germination medium to Epidnedium sp.20Gy can improve the germination rate compared with control group,shorten the germination time. the half lethal dose of Epidnedium sp is 69.34 Gy.Through the statistical analysis of biological, plant height and leaf length had significantly inhibited with the increase of radiation dose, the following was leaf number, had no effect on leaf width. Plant leaves appeared variation with the disposition of 120 Gy.