The Establishment Of Wheat Transformation System Mediated By A. Tumefaciens And The Studies On Transgene

Wheat (Triticum aestivum L., 2n=42, AABBDD) is one of the most important food crops in the world. Using of plant genetic engineering technology for genetic improvement of wheat is a new important way to enhance the insect-resistant and anti-adversity capacity, increase production and improve quality.Mature embryos of 104 wheat genotypes were cultured to compare the efficiency of induction, differentiation and regeneration of mature embryos callus among them. The factors influencing the induction, differentiation and regeneration of mature embryos callus were studied. The genotypes, whose the efficiency of induction, differentiation and regeneration of mature embryos callus were high, were screened. The mature embryos callus of genotypes screened were transformed by Agrobacterium tumefacienens-mediated (LBA4404/pNAR305). The factors influencing the efficiency of transformation mediated by A. tumefaciens were researched. The major results showed that:1. The genotype, metal ion, concentration of plant growth regulator and so on were important influencing factors for the induction, differentiation and regeneration of wheat mature embryos callus. Some of excellent wheat material including SN2618 and so on with the high efficiency of induction, differentiation and regeneration of mature embryos callus were selected out from 104 wheat genotypes via embryo-isolated method (EI). The optimal method of induction, differentiation and regeneration of mature embryos callus of these genotypes were determined. The optimized system of induction, differentiation and regeneration of wheat mature embryos callus was established.2. A. tumefaciens cell density and inoculation time, co-culture temperature and time, osmotic pre-culture, surfactant treatment were important influence factors for transformation of wheat mature embryos. A. tumefaciens cell density, inoculation time and selection pressure of selection reagent were confirmed; At the condition of 22℃training 3 d, the frequency of resistant callus will receive the maximum rate to 7.37%; Osmotic pre-culture before infection (0.4mol·L- 1 mannitol treatment 16h or 90g·L- 1 sugar treatment 18h) and surfactant treatment (0.02%Silwet-77) were help to improve transformation efficiency. The system optimized relatively of genetic transformation of mature embryo of wheat seed mediated by A. tumefacienens was preliminarily established.3. We transfered proteinase inhibitorⅡgene and prosystemin gene into SN2618, and got transgenic plants. Molecular detection for transgenic wheats had been done, and the useful genes had been transferred into them after PCR analysis.