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Cotton (Gossypium hirsutum) is one of the world's most important economic crops. Cotton fiber is an excellent natural fibers, because of its low cost, the output of large, good thermal properties, is considered excellent textile raw materials. With the development of the textile industry, the new textile technology growing need for better quality, higher strength of cotton fibers. Through conventional cross-breeding in recent years, has received a variety of fine varieties of cotton, however, due to the long cycle, excellent germplasm resources, making the process of hybrid cotton breeding restricted. Therefore, by means of genetic engineering conducive to the development of fiber into cotton and cotton-enhanced stress resistance genes, to improve the yield and quality of cotton fiber to increase stress resistance of the varieties, will provide new cotton breeding resources. Sucrose phosphate synthase can catalyze UDPG and 6 - phosphofructokinase generation 6 - sucrose phosphate and UDP, is one of the key enzymes in the sucrose metabolism. The enzyme has an important role in the development of the secondary cell wall cellulose synthesis, and can affect the development of the flower; addition, sucrose phosphate synthase can increase stress resistance in plants. This topic Arabidopsis (Arabidopsis thaliana), cotton material, obtained by RT-PCR of the the Arabidopsis sucrose phosphate synthase gene (AtSPS5.1) by gene-walking and over-lap PCR cotton sucrose phosphate synthetase the enzyme gene (GhSPS1) Final Construction AtSPS5.1-pART overexpression the carrier and GhSPS1-Part interference vector, to the genetic transformation of cotton. Its purpose, on the one hand, to lay the foundation for further study of the function of sucrose phosphate synthase cotton; cultivate genetically modified cotton on the other hand new germplasm, to provide material for further excellent fiber quality, strong resistance of new varieties of cotton. The results of this experiment are as follows: 1, was obtained by RT-PCR the Arabidopsis AtSPS5.1 gene. This gene is 3251bp, including the coding region of 3132bp encodes 1043 amino acids, with the other species of the SPS gene percentage similarity analysis, found their similarity were higher than 60%, and having the SPS conserved domains; use pKannibal and pART27 carrier successfully constructed a AtSPS5.1 over-expression vector. 2, using gene-walking and over-lap PCR method, obtained GhSPS1. The results showed that the gene is 4545 bp, and contains 12 introns, 13 exons and an open reading frame of 3108 bp encoding 1035 amino acids. After bioinformatic analysis confirmed SPSA family genes. Blast analysis to select the specific fragment was successfully constructed GhSPS1-pART interference carrier. 3, by real-time PCR method synthesis the four gene (GhSPS1, GhSUS3, GhINV, GhCESA4) organization and fiber development of sucrose-specific expression analysis, to show that GhSPS1 and GhSUS3 is constitutively expressed, but 0 DAF 3 DAF ovules and 18 DAF, the fibers of the highest expression level, in the fibers of the expression amount of 3-15 DAF GhINV GhCESA4 18 DAF fibers highest expression. Through the semiquantitative PCR detected GhSPS1 gene expression under abiotic stress conditions mode, the results show that the gene expression level decreased expression was increased in the ABA, low temperature processing conditions under drought conditions in the high temperature stress under elevated expression levels decreased. 5, using different media, culture of cotton cotyledon and hypocotyl induced callus occurred. The results show that, in a different medium, hypocotyl more rate higher than the cotyledons, and also has a significant advantage in the amount of growth; hypocotyl explants, different media on callus induction rate and callus state differences, which MSB 0.1 mg / L 2,4-D 0.1 mg / L KT 3% glucose minimal medium, the plant gel coagulant showed a clear advantage. 6 in cotton 24, Coker 310, Coker 312, 10 four cotton seeds in cotton material to explore the phenomenon of browning in tissue culture of cotton, the results show that, PVP can effectively extend the callus culture time, but can not fundamentally inhibit the browning; the dark treatment explants explant browning can be suppressed, but it is difficult to obtain normal induced callus; with glucose as carbon source, the sterilizing time is shortened to 15 minutes can effectively inhibit callus Browning. 7, the experimental optimization cotton Agrobacterium-mediated genetic transformation system to study the impact of conversion factors, the results show that, when the Agrobacterium concentration OD600 = 0.4, sterile Miao Miao age of 9 d, infection time 5 min total incubation time of 48 h, the highest conversion efficiency. 8, cotton (cotton 24 and cotton 10), genetic transformation, overexpression and interference resistant callus transformed by Agrobacterium tumefaciens LBA4404 mediated transformation method, preliminary PCR and RT-PCR detection prove positive callus. The comparison of the two transgenic cotton material found overexpression of type material callus rate, better growth state, significantly better than the interference type.
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