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The bad environment, such as low temperature,drought,salt, and other nonbiologi -cal adversity are the factors that the nature is widespread to repress plants growth existently, these conditions could cause many physiology bio-chemical variety, the plants must adapt these conditions and then they can exist enough. As lack of drought-tolerant plant material, in particular the lack of Joe shrub species, has seriously hampered the northern’s salinity ecological construction and economic development in rural areas.our country is a nation that water resources is in scarcity, dry and half dry farmland accounts for 38% of total national farmland; our country still contain a lot of salt soil needed to be exploited,how to develop and make use of the salt soils, the poor and unproductive lands of the big area , not only is the demand of increment agriculture in our country that can make use of the resources, also is the demand of improving the ecosystem environment, the increment green plants, overlay the rate of exaltation forest. Our forestry production urgent need some splings which have higher economic and ecological benefits. As long cycle of tree species, using conventional breeding techniques improved forest resistance heavy workload, long term, lead to improved varieties of trees nurture progress has been slow to meet ecological construction and economic development needs.The modern technology development provided the new method and paths for the farm crop species that grows the anti-to go against, having already become the economic and valid means of improvement the salt soils.The Robinia pseudoacacia and the Sophora japonica have many utility, our country has the cultivation everywhere, having the important ecosystem and economies value to use, If tolerance can be increased, which will having the very important meaning towards backing the farmland to return the wood, developing livestock husbandry and improvement the ecosystem environment. This research mainly optimized the regeneration system of the Robinia pseudoacacia firstly, which provides the dependable basis of turn the genetic engineering. at the same time, The gene pis has the anti-resisting function of dry and salt, therefore, making using of the Agrobacterium-mediated transformation of pis gene in the Sophora japonica, in older to acquire the new species with the anti-drought, anti-salt, thus enlargement expansion area, improving the ecosystem environment. The main research result is as follows:1. The optimization of Robinia pseudoacacia regeneration system.Used stem of Robinia pseudoacacia as the materials which were inoculated on the CNB (MS+1.8 mg/L NAA +1.1mg/L BA) medium adding different concentrations of kanamycin.When the concentration of kanamycin was 50 mg/L , callus were obviously swollen, loose, and the induction and growth of adventitious buds almost completely inhibited, so the 50 mg/L concentration of kanamycin was screening lethal concentration. The type and concentration of the hormone in medium had a significant effect to induce adventitious buds. After 10 d training with the CNB medium, the stems were transferred to DN medium (containing a certain concentration NAA, BA, ZT, 2, 4-D MS medium) which was added 50mg/L kanamycin.The two-step induction had not only increased the bud differentiation rate (94%), but also achieved the screening purpose.2. The Sophora japonica transformation with pis gene by Agrohczcterium tumefaciens.According to the Agrobacterium-mediated transformation, the PIS gene was turned into the Sophora japonica. The results showed as follows: (1)The big leaves of absorbing the more nourishment were the most optimum explants; the leaves didin’t pre-culture;(2)The D600 of Agrohczcterium tumefaciens was 0.3; (3)Using liquid differentiation medium was the best , infection time for 15 min; (4)The best co-culture time was 3 days , the co-culture medium pH was 5.5;(5)Best dark time was 15 to 20 days, that was a leaf from the Agrobacterium disseminated after the media, then turn to renewable in 15 to 20 days, placed under cultivation in the dark, after it, turn to the normal training cycle of day and night light, light time 14h.d-1;(7)The transgenic plants by distinctive PCR and Southern PCR,1700bp positive signals were obtained, the first step indication that PIS gene may be already integrated the genome of Sophora japonica;(8)Transgenic plant cultivation, the transgenic plant subculture 20 to 25 days, putting healthy seedlings directly into the rooting medium, 10 to 15 days, more than 90 percent of the seedlings have roots.According to gene gun-mediated transformation for gene transformation, the results showed as follows: (1) best explants infiltration processing time was 24 hours, mannitol concentration of 0.1 mol / L; (2) the best time for the low temperature was 12 hours.
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