Studies On Transformation Of Lespedeza Formosa With BADH GENE

Lespedeza formosa is an excellent shrub for feedingstuff and it is also an tree species which can be used to conserve soil and water. It is significantly important for using saline licks effectively by improving the salt resistance of L. formosa in order to enlarging its planting region.In this work, high frequency regeneration and transformation systems were established base on the study of the factors affecting cotyledon node regeneration, selective efficiency and gene transfer efficiency. The BADH gene was introduced into L. formosa through the improved programs and the salt-tolerance of transgenic plants were increased. The main research work and results are as follows:1. The effects of 6-BA,2,4-D,NAA,IBA,sucrose and seeding age on regeneration,segment proliferation and rooting ability were studied through the orthogonal designs of L16(45) and L9(34) , and the high frequency regeneration system of L. formosa was established. The results showed that the optimal medium compositions for adventitious buds regeneration from cotyledon nodes was MS+0.5mg.L-16-BA+1.0mg.L-12,4-D+0.5 mg.L-1NAA, the optimal medium compositions for segment proliferation was MS+1.0mg.L-16-BA+0.05mg.L-1NAA, and the optimal medium compositions for rooting was 1/2MS+0.4mg.L-1IBA +0.2mg.L-1NAA+30g.L-1 sucrose. There was no obvious difference among various seeding ages for the regeneration ability of cotyledon node.2. The target gene—BADH and the mark gene bar were gained separately from the pMD18-T vector and the pBI121-bar through PCR. The plant expression vector pBIBADHbar was constructed when the target gene and the mark gene were inserted into the pBI121, and it was transformed into LBA4404,EHA105 and C58 individually.3. The bacteriostasises effect of Cefotaxime(Cef) and Carbenicillin(Carb)were studied.