Transformation and expression of high molecular weight glutenin subunit genes in common wheat (Triticum aestivum L.) varieties

To explore the feasibility of improving wheat quality by genetic engineering, three Chinese winter common wheat varieties Een1, Emai11 and Emai12, were transformed with high-molecular-weight glutenin subunit (HWM-GS) genes 1Ax1 and 1Dx5 + 1Dy10 by particle bombardment, respectively . A significant negative correlation between plant regeneration frequency and the age of immature embryo were observed in all three tested varieties. The best transformation frequencies were achieved up to 4.5%, 2.9% and 2% for three varieties of Een 1, Emai 11 and Emai 12, respectively, when using immature embryos from young donor plants developing 12 to 14 days after blossoming. The phenotypically normal fertile T0 transgenic wheat plants of HMW-GS genes 1Dx5 + 1Dy10 and the endosperm-specific expressed T1 transgenic seeds were produced. Factors including explants at an optimal developmental stage from donor plant and optimal conditions of bombardment and tissue culture were proved to be the key parameters in the successful transformation procedure.