| In the first part of this thesis, the biolistic bombardment transformation systems for Lolium perenne and Zoysia sinica were established and introduction of some useful genes agronomically were introduced. In the second part, two useful genes were transformed into Lotus corniculatus and Medicago saliva by both . igrobacterium and biolistic bombardment.Establishment of biolistic bombardment transformation system in gramineous forage and turf grass plants and its transformation with exogenous genesThe application of biotechnology is fast and convenient in developing and improving new turf and forage grass varieties. An efficient tissue culture protocol was necessary for genetics transformation of plants. Tissue culture had been so difficult to manipulate in Gramineous forage and turfgrass. So this paper focused on the establishment of Lolium perenne and Zoysia sinica tissue culture system and genetic transformation protocol. In this condition, a series of transgenic Lolium perenne plants with resistant aridity, freezing and fungal disease have been obtained.As the first step, pBNAS vector was designed by cloning nicotianamine synthase (NASHOR1) gene from the barley genome and was introduced into the plants.While Lolium perenne initiation and regeneration protocol for embroygenic callus was established. The results showed that MS medium was the best basic medium for initiation and subculture of the callus amongst all the media tested. Initiation callus efficiency of Chunchao variety was the best of all in MS medium. 5mg/l 2,4-D was preferable concentration of plants hormone in induction culture and subculture of the callus. With supplement of 2mg/l ABA and 0.05mg/l 6-BAPthe quality of calli can be improved and the rate of embryogenic calli was increased; phytagel was better gelling agents than the homemade agar.50-75mg/l selective scope of selective agents G418 and 40-60 days of selective period were feasible.Biolistic bombardment transformation of 250l^g gold powder absorbing l^igDNA per shoting with HOOpsi helium pressure, and 6cm bombardment distance was the best combination. The transformation efficiency was also improved by treating calli on osmotic medium with 90mg/l mannitol for 12h before and 24h after bombardment.Using the particle bombardment transformation system nicotianamine synthase gene. CRT/DRE transcriptional activator binding factor(CBFl), T4 lysozyme gene were introduced into the callus of Lolium perenne. and 20, 12 and 9 lines of transgenic plants separately were obtained. PCR, Southern blotting, dot blotting analysis showed that target genes were integrated into the genome of the transgenic plants. Transgenic plants displayed the excellent resistant drought by expression of NASHOR gene in the field aridity experiment. The further observation in field experiment and identified resistance for these transgenic plants are underway.On the other hand, the tissue culture and regeneration procedures of Zoysia sinica and Poa prantensis were established for the first time, and freezing gene CBF1 was introduced into the callus of Zoysia sinica by biolistic bombardment, and kanamycin resistant plants of Zoysia sinica obtained.Transformation of legume forage plants Lotus corniculatus and Medicagogo sativaLeguminous forage plants, including Lotus corniculatus and Medicagogo sativa are the world's important forage crop with many favorable agronomic properties: abundant nutrition, withstanding freezing, drought, waterlogging, infertility, trampling, and very palatable to grazing animals. Especially, protein content in Medicagogo sativa is about 17-20%, and Lotus species do not cause bloating disease in grazing animals due to the presence of condensed tannins in their leaves and stems. Biotechnological breeding methods of grass plants were attractivebecause of many difficulties traditionally. By molecular methods forage plants with higher biomass yield, enhancement of the assimilation and efficient absorb of Fe element, and better abiotic and biotic stress resistance ca...
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