Study Of Breeding And Stress Resistance Of Three Wild Flowers Of Gesneriaceae

It is the distribution and diversity center of China for the subfamily Cyrtandroideae Endl. Emend. Burtt. The majority of wild native species are of high ornamental value but endangered because of severly damaged habitat. So the conservation of the rare plants and cultivation of that of commercial development value are need to study in depth for physiological and breeding technologies.The three plants we studied which have beautiful flowers and leaves,exotic flowers,long flowering and high ornamental value are of huge market and developing prospects. This is a comprehensive study of their habitats, phenology, rapid propagation and stress resistance. We are seeking the ways for their domestication and commercialization, we try to develop them into products of ornamental flowers and enrich our gardening landscape.The results as follows:⑴Tthrough the introduction and cultivation experiment, the plants of Gesneriaceae are relatively introduced easily under the simulated habitat conditions. The key of the cultivation process is shading, soil humidity and air circulation. It can be seen Boea clarkeana Hemsle has obvious advantages to the other two in flowering.⑵Through the techniques of Tissue Culture and Rapid Propagation, we find Didymocarpus Heucherifolius Hand.-Mazz.and Boea clarkeana Hemsle both can obtain sterilized material by explant leaves and Briggsia chienii can obtain sterilized material only by seeds. The three ones can all achieve the whole process of tissue culture, and growing well. The results showed, for Briggsia chienii, MS+NAA0.1mg·L^-1+6-BA0.1mg·L^-1 is the best medium of shoots differentiation, MS+NAA0.1mg·L^-1+6-BA0.2mg·L^-1 is the best medium of shoots proliferation,and 1/2MS is the best medium of rooting; for Didymocarpus Heucherifolius Hand.-Mazz, MS+NAA0.5mg·L^-1+6-BA 1 mg·L^-1 is the best medium of shoots differentiation while Boea clarkeana Hemsle is MS + NAA 0.5 mg·L^-1+6-BA 1mg·L^-1.The results of cutting propagation showed us the three ones have significant differences between the difficulty of rooting. Didymocarpus Heucherifolius Hand.-Mazz. didm't root, Briggsia chienii and Boea clarkeana Hemsle began rooting after 15 days, and root completely after 23 days. We learmed from the data that Boea clarkeana Hemsle has the highest rooting rate. ⑶Integraded 6 physiological and biochemical indexes such as Pn, Gs,Tr,etc. We learmed the capacity of shade tolerence is:Boea clarkeana Hemsle>Didymocarpus Heucherifolius Hand.-Mazz.>Briggsia chienii. Integraded 8 physiological and biochemical indexes such as membrane permeability, content of proline and MDA, We learmed the capacity of drought tolerence is:Boea clarkeana Hemsle>Didymocarpus Heucherifolius Hand.-Mazz.>Briggsia chienii.