Primary Investigation On Particle Bombardment Mediated By Co-transformation Of Wheat And Analysis Of Saline-alkaline Tolerance Of TaCHP Transgenic Lines

Common Wheat (Triticuma aestivum.L) is one of the major cereal crops in the world. As salinization is a negative factor of the yield and qualities of wheat, cultivating new salt-tolerant varieties would be one of adaptive strategies to cope with this stress. As limited by the common gene pool and of wheat, it is being really difficult to obtain salt-tolerant species by traditional hybridization. Genetic transformation offers an opportunity for creation of new transgenic wheat germplasm with salt tolerance.To limit the potential biological security risks, the minimal expression cassette co-transformation by particle bombarment is adopted. this technique reduce the security risks caused by the vector skeleton sequence. And transgenic plants without the marker gene can be detected from the offspring. Scaffold attachment region (SAR) is combined with the transformed DNA fragment to improve the stability of exogenous gene expression.It has proved that the T4generation of TaCHP transgenic line shows high tolerance to NaCl stress and genetic stability. In this research, it was confirmed that the exogenous gene was existed stably in the T5generation of transgenic lines. And parameters of germination of transgenic lines were compared with the control by treating their seeds with NaCl solution and alkali-saline soil individually. The pustulation period and mature period related agronomic traits and physiological indices of transgenic lines and its control planted in alkali-saline soil of experimental field of Dong Ying were compared. To avoid the biosafety problems of vector backbone sequence in genetic transformation, the methods of biolistic particle co-transformation mediated gene expression cassettes lacking vector backbone sequences was used to transfer salt related TaCHP gene into calli derived from immature embryo of wheat.The main achievements are as follows:1. TaCHP gene was successfully inserted into the calli derived from immature embryo of Hesheng3, Kenong199by particle bombardment co-transformation mediated minimal expression cassette of plasmid psTaCHP gene and psBAR. The transgenic plants were confirmed by Basta selection and PCR verification.2. Stable integration and inheritance of the T5generation of transgenic lines were confirmed by molecular analysis. By comparing the germination factors, it showed that the germination and growth of transgenic lines were slower in the alkali saline soil than in200mmol·L-1NaCl solution and the differences were analyzed.3. The similarities and differences of yield related agronomic characters and physiological index during pustulation period and mature period that exist between transgenic lines and parental control cultivated in alkali saline field were compared. And it deduced that the high yield production of transgenic lines is likely to improve the effective tiller number during tillering stage and increasing the effective protection of the photosynthetic system during pustulation period.