Agrobacterium-mediated Chitinase And Beta-1, 3 - Glucanase Gene Conversion Cucumber

In the present studies, the chitinase and P ?, 3?glucanase genes were transformed to cucumber genome (Cucumis sativus L.) by the ,4grobacterium tumefaci ens LBA4404 in which the plasmid PCGIIis the binary vector for the two gene transformation. The two genes were cloned from the Nicotiana tabacum and could express extracellularly in plant. The optimum transformation system and the regeneration system of hypocotyl segments and cotyledon discs were also studied The results showed: In the optimized regeneration system, the callus induction media for the cotyledon of inyanNo. 4 ?and hangchongmici?were MS2, MS8 and MS1 The regeneration media for the two kinds of varieties were MS8 and MS10 A3(l/2MS) was used as root induction media for the transgenic cucumber plants. In the optimum transformation system, the optimum explants for coæ¢'ultivation were taken from the 3 o.d seedlings; The optimum bacterium concentration in value of OD6(J was 0.6(about 108 cells/mi). It had the best promoting effect on the transformation when the acetosyringone concentration ranged 40 and 50 ii mol/L. To cotyledon discs, the optimum time of preculture and infection were 24 hours and 15 minutes respectively. To hypocotyl explants, they were 36 hours and 10 minutes. To the hangchongmici?and inyanNo. 4? hypocotyl segments and cotyledon discs, the optimum time of co? culture were 3, 4 and 4, 5 days respectively. The selective pressure during the callus induction, regeneration and rooting stages was Kanamycin 75mg/L. In the transformation of cucumber using chitinase and the β? 1,3 lucanase genes, transgenic plants were obtained from both inyanNo. 4?and hangchongmic 1? The opine assay showed that they were transformed plants. The primary detection of disease resistance with Fusarium oxysporunz f. sp cucumerinuz Owen showed that these transgenic plants had more resistance to this pathogenic fungus.