| Wheat ,a major world crops, is primary target for thre application of genetic engineering to improving agronomic characteristic. In this paper, the regeneration system of four genetypes wheat was established. the immature embroys calli used as receptor to be bombardment with gold partical coated with herbicide resistance of Bar gene and the parameters of bombardment were optimized by GUS transient expression. After callus induced regeneration and shooted elongation on selection with PPT, total of 33 resistant plants were achieved. By PCR analysis and spreads the leaf examination with PPT in T0 regeneration, 4 transgenic plants were identified with a transferent frequency of 0.33%. In addition, we transfer the wheat Bar gene into wheat cultivated varieties with backcross way. Then by the tracking investigation of the herbicide resistance of generations crossed or backcrossed with Bar gene transgenic wheat and the wheat hybrid descent's heredity performance were studied. The result indicated that: 1 Development of regeneration systemsWheat genotypes and medium are the key factores influencing the development of regeneration systems for immature embryo cultivation. As far as the frequency of callus induction,quality of callus induction,frequency of compact differentiation and regeneration were concerned, there was a trend of Yangmai 158>Annong 98005>Wanmai 33>Annong 92484. A effection regenaration system had been established : callus induction medium was MS+2.0 mg/L 2,4-D+0.5 mg/L ABA. After beeing treated in 4℃ low temperature, the callus were regenerated on MS+1.0 mg/L KT+0.2 mg/L NAA medium. Then shoot were induced on 1/2 MS medium supplemented with 0.4 mg/L NAA,and 0.6 mg/L PP333. In such system, the callus regeneration frequency had the remarkable elevation.2 Development of bombardment transformation systems Under the vacum pressure of 91.4×103~94.9×103 Pa and bombarded once per dish with the Helium pressure of 1100Psi, conditions of bombardment were optimized by GUS transient expression. The results indicated that when the precipitants for coating particles containing 50 μl 2.5mol/L CaCl2 and 20 μl 0.1mol/L spermidine, the suitable dosage of DNA and gold powder per bombardment was 250 mg/0.5 μl and the bombardment distance was 9 cm, the GUS expression get the higest expression. The acceptor materials were cultured on osmotic medium (0.4 mol/L osmotic agents) 4 hours before bombardment and 16 hours after bombardment. 3 Transformation and selection Selection system of high efficiency was determined by different PPT concentration. Callus growth inhibition ,regeneration and rooting were 3 mg/L,5 mg/L and 15 mg/L. 4 plants were proved transgenic including Yangmai 158 and Annong 98005 by PCR anlysis. The herbicide-resistance test on the plants leaves indicated that two plants were more resistant than the other two. It suggested that Bar gene were expressed on different level. The wheat transformation frequency was between 0.33~0.66%, and cultivated time was only about 3~4 months.4 Through the hybridization of Anhui local wheat cultivated variety and the herbicide resistance variety which is including Bar gene by genetic engineering, the herbicide resistance F1 generation plant were obtained which was self-crossed or backcrossed with Anhui variety. The separation in F2 between the resistance and sensistive basically according 3:1, while in B1F1 generation is 1:1. The result showed that the inheritance of Bar gene was a single dominant gene and accorded with the law of Mendelian segregationbasically.
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