Transgenic Zoysia japonica plants obtained by biolistic bombardment transformation

Embryogenic calli induced from zoysiagrass(Zoysia japonica Steud.) seeds were bombarded with gold particles coated with double-gene vector plasmid containing DREB1A and gus gene.Physical bombardment parameters were evaluated by transient expression of gus gene,and the best result was obtained by a target distance of 6 cm and twice bombardments under the pressure of(1 100) psi, while the concentration of gold particle and plasmid had no significant effect on the transformation efficiency.Stable gus expression was observed in hygromycin-resistant calli,while regenerants survived hygromycin selection and showed gus-activity.PCR-Southern blot analysis further indicated that the foreign gene DREB1A had been integrated into the genome of recovered zoysiagrass plants.