Studies On Insect-resistant Transgenic Maize Transferred Bt Gene With Marker-free

With commercialization of transgenic plant increasing, the biosafety is always concerned by scientists and governments. Since selectable maker genes are existed in almost all transgenic plants, the biosafety of marker genes are concerned by the public. So various methods and strategies are currently being developed for the maker gene excision and elimination from transgenic plants.Double T-DNA plant expression vector pCDMAR-USBK-Hyg was derived form plasmid vector pUBK and double T-DNA vector pCDMAR-Hyg. One T-DNA construction contains plant selectable maker hygromacin phosphotransferase (hpt) which driven by CaMV35s promoter, the other T-DNA construction contrains Bt gene which was flanked by two MAR sequence. The Bt gene what was obtained from pUBK was driven by ubiquitin promoter. Then the double T-DNA vector was transferred into Type II callus of maize elite inbred via Agrobacterium-medialed. Some fertile transgenic maize had obtained. Result of PCR, PCR-Southem confirmed that transgenic plants carry the foreign gene.By now, T1 seeds had been obtained.