Exploration Of The Transformation System Of Caragana Korshinskii Kom. And Identification Of CKF5H Transgenic Arabidopsis Thaliana

Caragana korshinskii Kom., in the genus of Caragana, Fabaceae family, is a tall shrub common in the sandy desert of Central Asia. Caragana korshinskii has been treated as a dominant tree species that is planted as a windbreak to protect soil in arid area and to return farmland to forestry in the Loess Plateau. Caragana korshinskii has an astonishing adaptability and thus it is of great significance to study its potentially favorable resistance genes for species diversity preservation and biological sustainable development.Lignin is a natural kind of macromolecule, it is widely spread in plants. Lignin can be degraded because of the special structure characters, thereby being a good choice in dealing with an increasing demand for energy resources. A certain application values and environmental benefits can be achieved by regulating the biosynthesis and degradation of lignin in genetic engineering to improve the use ratio. In the paper, the genetic transformation system and tissue culture about Caragana korshinskii Kom. was explored through the experiments, besides the functional identification of CkF5H transgenic arabidopsis line was performed. The achievements acquired are given as below:1. The Caragana korshinskii seeds were in chlorine processing for18h with a low pollution rate and no adverse effect on the seed germination.2. The genetic transformation system of Caragana korshinskii was initially established using the callus induction method with cotyledon nodes as the explants. In the medium with2mg/L6-BA and0.5mg/L2,4-D, the callus induction rate was high and bud proliferation number was2.5. The survival rate of over95%was found when the buds were transplanted into soil. As a result, the genetic transformation efficiency was0.42%..3. The CkF5H expression vector was successfully constructed. By agrobacterium-mediated transformation system of arabidopsis thaliana, transformations of wild-type arabidopsis and fahl-2mutants were achieved, leading to six over-expression arabidopsis and six complementary lines.4. There were no effects on the normal arabidopsis growth existing in the case of the over-expression of CkF5H gene. Staining results showed the arabidopsis mutants were complemented by the CkF5H gene and S lignin recovered to the usual wild-type level. Therefore, it can be concluded that CkF5H is capable of promoting the conversion from G lignin to S lignin.