Improvement Of The Technique System Of Tissue Culture And Rapid Propagation And Study On The Heat Resistance Of Rhododendron Chrysanthum Pall

In this study,the wild Rh.chrysanthum Pall.of Changbai mountain as test material,further Study on tissue culture technique of Rh.chrysanthum Pall.to improve its technique system of tissue culture and rapid propagation,for its scale production and expanding Rh chrysanthum Pall.population number lay a foundation.At the same time,the effect of EMS treatment on Rh.chrysanthum Pall.heat resistance and the possible mechanism of heat tolerance were explored to lay the foundation for the application and innovation of germplasm resources Rh chrysanthum Pall..The results were as follows:1 The suitable proliferated medium of Rh chrysanthum Pall.tissue culture plantlets was modified MS+IBA 3.0 mg·L^-1+ZT 1.5 mg·L^-1,and proliferation times reached 5.21.After adding coconut milk,the proliferation multiple and plant height were significantly increased,and the leaves were more dense,and the branches increased obviously.The best concentration of coconut milk was 150 ml·L^-1.2 The suitable medium for the rooting of the tissue culture seedling of Rh chrysanthum Pall.was 1/4modified MS+IBA 5.0 mg·L^-1+AC 1.5 g·L^-1,and the rooting rate reached 88.89%,which shorten the rooting culture periods of Rh.chrysanthum Pall.Activated carbon had little effect on the rooting rate of the tissue culture seedling,but it could improve the aeration status of the rhizosphere,which resulted in the improvement of the number and length of the root in some extent so the plant growth was better.3 The suitable transplanting matrix composition of Rh.chrysanthum Pall.tissue culture plantlets was peat soil:humus soil:perlite=2:1:1.The transplanting survival rate was the highest,which was 95.66%.4 After the leaf of the tissue culture seedling were treated in medium within 0.1%EMS for 2 d,the survival rate of leaf was 48.9%.The EMS concentration and treat time could be used as the suitable screening condition of heat resistant mutants.5 After treating regenerated plants from the EMS treated leaves and the control group with different heat treatment,the related physiological indexes measured had differences in the larger.With the increase of temperature,SOD,POD activity and Pro,soluble sugar content of plant showed the trend of first increased and then decreased.At the same temperature,induced group was significantly higher than that of control group,and at 35℃ or 40℃,difference of them got the biggest.Chlorophyll content was declined,but at the same treatment temperature,induced group was significantly higher than that of the control group,and MDA content was significantly lower than that of control group,which indicates that EMS treatment improved the heat resistance of Rh.chrysanthum Pall.tissue cultured plantlets in a certain extent.