Studies Of Introduction Of Sucrose Synthase Gene Into Cotton By Agrobacterium-mediated Vacuum Infiltration And The Function Of SuSy Gene In Transgenic Cotton

Cotton is the most improtant textile crop as a result of its long celluclose-enriched mature fibers. These single-celled hairs initiate at anthesis from the olvule epidermis. These results demonstrates that SuSy plays a rate-limiting role in the initiation and elongation or of the single-celled fibers, and influentialed secondary wall thickening speed. So , this study had developed SuSy transgenic cotton through Agrobacterium-mediated vacuum infiltration and pollen tube pasway, we studied the influence to plant metabolic level and agronomic traits. This work showed the function both yield improvement and cotton fiber of SuSy gene in transgenic cotton.Upland cotton pollen as the receptor,Sucrose Synthase Gene (SuSy ) was transfered to Xinluzao19 by Agrobacterium-mediated vacuum infiltration, the suitable conditions of vacuum infiltration method were determined .The medium consisting of 45%(m/v) sucrose was suitable , could maintain a proper infiltration press and the lower exploded pollen rate . Under pressure -80pa , OD600 0.6-1.2, in order to maintain the lower exploded pollen rate and higher transient transformation, the appropriate time of vacuum infiltration was 15-25 minutes . For Agrobacterium-mediated vacuum infiltrated pollen, a transient GUS expression assay and the exploded pollen rate proved that the Agrobacterium -mediated vacuum infiltrated pollen became blue. Those activated pollen would be pollinated on the stigma emasculated respectively. Result showed that pollen using Agrobacterium-mediated vacuum infiltration were activated and could germinate pollen tubes. In the T1 generation , 23 plants showed kanamycin-resistance . And , PCR amplification confirmed that 18 plants of them had specific fragment of SuSy gene, but no specific fragment appered in negative control,transformation rate is 0.3%.And the use of pollen-tube pathway to get SuSy gene transgenic cotton for the material: in this study we proved that SuSy gene in upland cotton, containing and expressing the SuSy gene respectively, PCR and Southern blot analysis confirmed their transgenic status: PCR result was that there was no specific band appered in negative control, but a specific band similar to positive contol was amplified from the test sampel; Southern blot result was there contained a single copy of the transgene . At the same time , according to comparison of traits, yield and fiber quality traits T5 generation and receptor Xinluzao13. The results showed that exogenous gene into the cotton agronomic traits to different extents, the coefficient of variation increased characters, a few fruiting branches and lint yield significantly; Plant leaves and stalks of epidermal hair intensive than the control volume significantly increased five times; Fiber length and intensity of a slight increase, Micronaire Value lower,quality has improved. Studied on various types of sugar content changes of transgenic cotton ,the results showed that: transgenic fiber lower sucrose content. In soluble sugar and cotton fibers into the final of soluble sugar content, cotton fiber in soluble sugar content to drop by much of the cellulose synthesis and deposition.Determined the impact of the use of technology to raise the quality of cotton fiber, laid the theoretical foundation.Transgenic cotton is expected to provide good quality breeding material.