| After the first tobacco insect-resistant transgenic plant was reported in 1987, more than 40 kinds of insect-resistant genes have been transformed into dozens of crops, and many field trials of crops expressing Bt genes have been carried out. Some of these crops like cotton, maize and potato have been used in commercial application. In recent years, Great progress has been made in Agrobacterium-rnediated transformation in monococotyledon crop, but there still wasn't a method used in every variety. In this study, we established an efficient and quick Agrobacterium-medfated transgenic system of rice and has transformed three kinds of plasmids including CrylAc, CpTi and double genes into japonica rice Zheda19. We compared insect resistance between three kinds of transgenic plants. We also groped the best tissue culture condition of tall fescue. The major results can be summarized as below:Tissue culture is an important step in establishing cell selection and genetic transformation systems. The effect of different concentrations of 6-benzyladenine, the effect of light on callus induction, browning and GUS transient expression in Indica rice Pei'ai64S (thermo-period sensitive male genie sterile, TGMS) transformation was investigated. The results indicated that embryos callus from seeds and GUS transient expression was favored by the addition of concentration 6-benzyladenine to cultured medium and culturing under light condition. An efficient and quick /Agrobacferium-mediated rice transgenic system has been established and the transformation ratio reached 14.5%.By yAgro/bactem/m-mediated transformation, the CpTi, CrylAc and double genes were transformed into rice Zheda19. It is the first time to compare leaf folder resistance between three kinds of transgenic plants. The resistant results displayed that there was different resistant degree in different resistant genes, and B310 harboring CrylAc had the highest resistance, while others harboring CpTi and CrylAc +CpTi had obvious resistance. Agronomic performance of T3 transgenic lines were- IV -analysed, the results obtained from field evaluation with transgenic lines of rice have shown that effective spike, panicle length, flag leaf length have no significant variation, but the data collected for other major agronomic traits including plant height, plant yield, 1000-seed weight and plant fertility were influenced on different level. Plant height, Panicle length and flag leaf length were influented in bidirection. Almost all of plant yield and 1000-seed weight decreased.Molecular analysis based on PCR detection in T3 confirmed that the target genes had been inherited to T3 progeny successfully. The expression of foreign genes at RNA level was demonstrated by RT-PCR also.The tissue culture research in turfgrass field including tall fescue was long drop behind food crops. In this thesis, sterilization method was improved and the ratio of contamination dropped. The induction of callus in tall fescue was studied on different media and different combination of 2,4-D, BA. The results indicated that 9mg/L2,4-D on MS medium obtained the highest induction frequencies of callus. The best differentiation media was MS+BA2.0mg/L+NAA0.5mg/L. The research also found that effects of synthetic plant growth regulators S-3307 and PP333 on tissue culture of tall fescue were highly correlated with different genotypes. In callus induction experiment, all the setup concentrations of S-3307 inhibited callus induction of Dixie Green and Houndog 5 varieties, but could increase the callus induction ratio of Gooden and Triple A. PP333 promote callus induction of ttiree kinds of varieties except Dixie Green. During plantlet regeneration, S-3307 and PP333 were found to assist in callus differentiation of all tested varieties except Gooden, and the best concentration was observed to be 0.01 mg/L and 0.1mg/L respectively. High concentrations (>1mg/L) of two plant growth regulators were detected to be toxic to callus induction and differentiation of four tested varieties.
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