Li Hanxia

Inheritance and resistance to insects in CryIA(c) transgenic cabbage

Using hypocotyl segments of aseptic seedlings of cabbage (Brassica oleracea var. capitata) as explants, regenerated plants with kanamycin resistance were obtained mediated by Agrobacterium tumefaciecin (strain LBA4404). The transformed plants with CryIA(c) (Bt) gene were confirmed by Southern blotting analysis. And the results showed that CryIA(c) gene had been integrated into the cabbage genome. And majority of the transgenic plants had only one single copy of the inserted CryIA(c) gene. Leaf section bioassays of insect resistance showed that CryIA(c) transgenic cabbage significantly enhanced the level of resistance against the larvae of insect diamondback moth (DBM). The inheritance patterns of the transgene in T1 offspring of transgenic cabbage were investigated using PCR with NPTⅡ primers and kanamycin resistance test on young seedling leaves. The results showed that dominant gene locus, CryIA(c) gene and NPTⅡ gene followed the Mendels fashion with a ratio of 3∶1 segregation in T1 populations.

Plant gene targeting and gene replacement: application to crop genetic improvement

Recent advances and limitations of using zinc finger nuclease to stimulate a high efficiency of homologous recombination, and chimeric oligonucleotides to promote single base replacement in functional genomic research and plant genetic breeding, are systematically reviewed. Approaches to improve gene targeting efficiency through molecular modification of key pathways in plant homologous recombination are also discussed.