Establishment Of High-frequency Regeneration System Of Populus And Study On Transformation Of Salt-resisting Gene

Factors affecting Pupulus tissue culture were explored systematically by culturing buds and leaves as in vitro material of binary female and male P.tomentosa as well as triploid female and male. High-frequency Regeneration System of five species of Pupulus were established;The result of PCR has showed: OsNHX1 gene was led into the genome of P.deltoides by Agrobacterium tumefaciens mediating gene transforming and salt-resisting transgenosis plant was acquired. Concrete operations are as follows:1. Tissue Culture and Establishment of High-frequency Regeneration System of Populus Selected and tissue cultured buds and leaves of five species of Populus , then induced them into regeneration. The best medium of regeneration of P.tomentosa is:MS+BA1.0(mg·L-1, the same as follow) +NAA0.1+GA0.5; Frequency of differentiation is 90% above; To P.deltoides, regeneration medium is: MS+BA0.5+NAA0.1+GA0.5;Frequency of differentiation is 99% above; Rooting-medium is: MS+ NAA0.1; 2. Difference of genotype in different species is the determinative factor which affects the regeneration ability of in vitro explants, but the effect of that in the same species is not obvious. Gene which modifies the regeneration ability of plants is not sex-chromosome-linked and has not folded effect with multiple of genome. 3. On the basis of establishment of Populus high-frequency regenerationsystem, the study of Populus heredity conversion of anti-salt gene mediatedand induced by Agrobacterium tumefaciens was carried on. Factors as optimumconversion state, infecting time etc were expounded. Resistant planet wasscreened by increasing concentration of Km step by step and roots were inducedin screening rooting-medium.With unconversed plant as negative tester andplasmid DNA as active tester, PCR was carried on. Result showed: extendedstrip in transgenosis plant agreed with target strip in plasmid while no stripextended in unconversed plant; this indicated external target gene wasintegraded into Populus genome.