Study On Optimization Of Rapid Propagation In Vitro And The Standards Of Seedling Degree Of Dendranthema Morifolium (Ramat) Tzvel.Cv.Gongju

Dendranthema morifolium (Ramat) Tzvel.Cv.Gongju belongs to the perennial herbaceous of Compositae, also named "Huangshan Gongju " or "Hui Ju", the capitulum can be used as medicine, which is one of the sources of medicinal chrysanthemum required by China pharmacopoeia. Dendranthema morifolium slightly cold in nature, sweetness and bitterness in taste, has the effect of dispelling wind and clearing heat, smoothing liver and clearing eyesight, and heat-clearing and detoxifying, which is clinical applied to treat wind-heat type common cold, headache and vertigo and various heat syndromes.And there are some preparations used in clinic, such as Qijudihuang pills, tabletsSambo. Huangshan Dendranthema morifolium, with homology of medicine and food, has great prospects in being the development of senior tea and care products.Dendranthema morifolium fails in sexual reproduction and fructifying. Therefore, Dendranthema morifolium has no seed. The asexual reproduction, such as Ramet and cuttings is the general techniques for Dendranthema morifolium’s nursery, which induces heavy continuous cropping obstacle. Besides, it is prone to the buildup of plant virus by multi-generational sub-yield, resulting in variety degeneration or variation.Objective:Optimize the vitro propagation system of Dendranthema morifolium, investigate the optimum conditions and rejuvenate the germplasm to provide a theoretical method and basis for accelerating Dendranthema morifolium’s breeding, while establishing the grading standard of seedling to lay the foundation for conserving Dendranthema morifolium germplasm resources, selectively cultivating improved seeds and standard planting.Methods:The experiments were carried out on the basis of team’s previous research. In order to optimize the the vitro propagation system of Dendranthema morifolium, the study mainly performed to investigate the concentration of various plant growth regulator, the formulation of the basic medium, inoculation method and density for planting and natural additives. The grading standard of Dendranthema morifolium seedling was proposed followed by a graded authentication via analyzing the biological indicators of the Dendranthema morifolium’s seed. Methods including single factor experiment, orthogonal design, and cluster analysis were adopted in this study.Result:1 Optimization of the culture conditions in vitro of adventitious buds induction and proliferation of Dendranthema morifolium1.1 The selection of material source and density:compare with leaf,uper and lower parts of stem, thin cell layer, apical bud did better in inducing adventitious buds.1.2 The Selection of Plant Growth Regulator:Both of 6-BA and KT within a certain range of concentrations had an impact on the adventitious buds, the auxin -- NAA or IB A increased the rate of adventitious buds, the optimum growth conditions was 6-BA 2.0mgL-1+NAA0.02 mg-L-1+IBA0.1 mg-L-1, with the multiplication coefficient up to 6.43±0.56.1.3 The optimized basic medium compositions were:basic MS macronutrients concentration+1.5 times Fe +sucrose 20g·L-1+coconut water 30ml·L-1.2 Optimization of the culture conditions in vitro of shoots strengthening, roots induction and acclimatization of Dendranthema morifoliumSingle factor and combinational experiments were studied, the results showed that the optimal hormone conditions for in vitro of shoots strengthening was MS+IBA0.1mg·L-1 +NAA0.2mg·L-1. The best seeding density was 5 plants in a bottle. 250-500mg·L-1 of casein hydrolyzate could obviously promote strong seeding, with sucrose as the optimum carbon source. The concentration of activated carbon(AC) suitable for Dendranthema morifolium rooting ranged from0 g/L to 1g/L, with the best ratio of 0.5g/ L. Pearlite was a suitable matrix for hardening, and the most suitable mixed matrix for hardening was:Dendranthema morifolium of:vermiculite:sand:garden soil= 1:1:1.3 Study on the standards of seedling Degree of Dendranthema morifoliumThe results of seedlings grading standards of Dendranthema morifolium showed as follow: Grade Ⅰ:H 2≥ 9.26cm, D≥ 0.30cm. Grade Ⅱ:H(9.26>H≥6.56), D (0.30>D2≥0.21); Grade Ⅲ:H<6.56cm, D<0.21 cm. Seed of grade Ⅰ and Ⅱ reached the requirements for transplating, Ⅰor Ⅱ seedlings were priority selection for planting. Conclusion:The study was based on the team’s previous research. In order to optimazing the the rapid propagation system in vitro of Dendranthema morifolium, lay a technique foundation for the Good Agricultural Practices, effects of concentration of various plant growth regulator, inoculum density and natural additives on vitro culture were studied, also culture effects and cost saving were considered in evaluating. Biological indicators of Dendranthema morifolium were analyzed, the results showed that height and ground diameter can be the indicator for the seedling grading standard. With clustering analyses, seedling quality of Dendranthema morifolium were divided into three grade. Survival rate and plant yield were observed to prove the rationality and feasibility of the grading standard.