Tissue Culture And High Efficient Regeneration System’s Establishment Of Ixeris Chinensis(Thunb.) Nakai

Ixeris chinensis (Thunb.) Nakai is perennial herb plant belongs to Composite family and Ixeris Cass. More and more people like it because of its important edible and medicinal value. Wild resources can not meet the needs of people and the speed of artificial cultivation is slow, so it’s particularly important to seek the method for rapid propagation. Induce callus differentiation and direct differentiation can both obtain regeneration seedlings of Ixeris chinensis, the high efficient regeneration system of Ixeris chinensis was successfully established, specific results are shown as follows:1. Callus induction, multiplication and differentiation(1) Callus inductionTender stems without buds of Ixeris chinensis were used as explants stapled and inclined to do the research on callus inducement in many different mediums for callus induction, the results showed that constant temperature illumination was facilitative for callus induction, the ideal medium for callus induction was MS+BA1.0mg·L-1+NAA0.1mg·L-1+sucrose30g·L-1, effect of stapled tender stems was better than inclined, the rate of callus induction was up to100%.(2) callus multiplicationThe results showed that MS+BA1.0mg·L-1+NAA0.1mg·L-1+sucrose30g·L-1was the perfect medium for callus multiplication; multiplication coefficient were respectively25.2,12.7and9.8with constant temperature illumination, constant temperature without light and poikilothermal illumination, the best condition was constant temperature illumination.(3) callus differentiationIntegrated all ideal factors, the optimum condition for callus differentiation was1/2MS+sucrose15g·L-1with constant temperature illumination, the rate of differentiation was100%, each callus differentiated5.6adventitious buds on average, average shoot length was1.2cm.2. Effects of different materials and conditions on direct differentiationMeristems, leaves, stipes and tender stems without buds of Ixeris chinensis were used as explants to induce direct differentiation. The results indicated that tender stems without buds were the best one of the four stuffs for direct differentiation without callus, MS+BA0.5mg·L-1+IBA0.5mg·L-1+KT0.5mg·L-1+sucrose30g·L-1was the perfect medium for direct differentiation, rate of direct differentiation was100%, each stem differentiated56buds with height of2.1-3.4cm on average.3. Effects of different conditions on rooting of differentiated budsThe results indicated that the best medium for rooting of differentiated buds was1/4MS+IAA0.2mg·L-1+sucrose20g·L-1, constant temperature illumination was the ideal condition; rooting effect of interpolation was the best one of the three kinds, rooting rate was100%, average number of roots from one tube seedling was7.6and average length of root was4.22cm.4. Proliferating cultivation of rootingObservation statistics after25d shown that survival rate and rooting rate of tube seedlings were both100%, average multiplication coefficient was up to4.8, rooting effect was perfect and there was almost no invalid seedlings. According to this propagation velocity, one tube seedling can theoretically produce4.814.6(approximately8800000000) plants.5. Refine seedling, transplanting and colonization1/2clays from garden+1/2sands was the best substrate for transplanting of regeneration plants, the transplanting survival rate was96.5%and stable planting survival rate was99%. The tube seedlings survivaled retained all biological characteristics of the escape Ixeris chinensis with exuberant growth.