Studies On The Tissue Culture System Of Euphorbia Royleana Boiss

This paper mainly dealt with micropropagation of Euphorbia royleana Boiss from axillary bud, callus induction and adventitious seedling regeneration from non-sprout stem and leaves , and differentiation of non-sprout stem blocks and leaves that taken from in vitro buds. The main results can be summarized as follows:1. The in vitro tissue culture of axillary buds: taking the stem of Euphorbia royleana Boiss with axillary buds as explants. In MS media with 6-BA0.5-2.0mg/L and NAA0.1-1.0mg/L bud growth can be induced, while the induction rate ranks the highest in the medium of 6-BA1.0 mg/L +NAA0.1 mg/L and MS+6-BA0.5 mg/L +NAA1,0 rag/L, reaching as high as 100% with well-developed bud. When 6-BA is increased to 2mg/L there is no evident influence on the budding rate, but the growth of bud is obviously restrained, meanwhile ,when NAA is only 0.1mg/L the bud become vitrification. When the induced buds is transferred into the culture medium of proliferation, the ideal culture medium of proliferation is MS+6-BA2.0 mg/L +KT1.0 mg/L +NAA0.1 mg/L with the proliferation coefficient of 7.4.2. Induction of callus: the callus induction of Euphorbia royleana Boiss is difficult. In several media aiming at callus induction the explants has only got few calluses which are seriously browning. Callus inducement of stem block is easier than that of leaves. TDZ functions well to both of the explants in the callus inducement while the leaves only get a few granular callus. TDZ can not only help the growth of callus on the edge of stem block, but also enlarge the block and stimulate granular protuberances on the epidermal which maybe the prototype of buds.3. Inducement of adventitious shoots, when the stem block is cultivated in MS+TDZ1.0 mg/L+NAA0.1 mg/L for around 30 days, the inducement rate is 100% and there are many granular protuberances on the epidermal; then transfer the block into MS+6-BA1.0 mg/L +NAA 0.1mg/L to get tufty leaves and would grow into strong buds after seedling strengthening. Put the whole leaves that cut from the in vitro buds into MS+TDZ1.0 mg/L+NAA0.1 rag/L, and green gemmas can be induced at the interface of the cutting and callus with the inducement rate as 57.1%. As the case of stem block, when this is transferred into MS+6-BA1.0 mg/L +NAA 0,1 mg/L tufty leaves can be derived herefrom, only that the prolonged buds are of small number and are abnormal.4. Seedling strong, rooting and transplantation: In the medium of MS+NAA 1.0mg/L+6-BA0.5mg/L, the leaves would grow, color deepen and the stem grow quickly. After strengthening for about 30 days the bud can be transferred into rooting medium. And in the medium of MS+IBA1.0 mg/L +6-BA0.1 mg/L the rooting effect is the best and can reach the rate of 100%. After a month's rooting, remover the lid of the bottle and refine the plants for 3 days, then transplant them respectively into basins containing Vermiculite, sand and perlite. The seedlings would gain new root 10 days after transplantation, and in a month they would sprout new leaves. The survival rate of seedling planted in perlite is the highest,reaching67%.