Analysis On Difference Of Carbon And Nitrogen Metabolism In Growing Period Of Flue-cured Tobaccos In Different Areas Of Liang-shan

Two representative ecological Huili and Puge were selected to study the flow distribution of the carbon and nitrogen metabolism and the differences of the secondary metabolism during the mature process of tobacco leaves.The results are as follows:1. Before 73 days after transplant, SPS and INV activities of tobacco leaves were higher in Puge, which showed that carbon metabolism was more exuberant.. The higher SPS activity resulted that tobaccos in Puge accumulated more fiber materials; the higher INV activity caused the reducing sugar content was higher in Puge than Huili. 73 days later after transplant, as the carbon metabolism of tobaccos may be blocked in Puge, the SPS activity dropped substantially, the aging started, the fiber materials began degraded, and the SS and INV activity had a certain degree of decline. The SS activity of tobaccos in Puge in this stage was lower than Huili, and tobaccos in Huili accumulated more cellulose in later stage.2. The nitrogen metabolism of tobaccos in the two areas showed that: the NR activity of tobaccos were higher in Puge, which indicated that the ability of using nitric nitrogen was higher in Puge. And GS and GOGAT activity was lower in Puge. It showed the ability of assimilation ammonia weaker than tobaccos in Huili. The GDH activity of tobaccos in Puge was significantly higher than Huili. Carbon and nitrogen metabolites feeding leaf discs showed that the sucrose and glutamate promoted the GS and GDH activity, the ammonium did not affect the GS activity apparently, and can inhibit the activity of GDH. Sufficient energy material promoted the GDH activity, when the carbon metabolism of tobaccos was blocked in Puge.3. PuGe tobacco 73 days later after transplant, the dramatic decline of the carbon metabolism of in Puge tobacco caused the phenypropanoids metabolism decreasing, and was not favorable for the accumulation of phenolic compounds. In order to explore the strength of the terpenes metabolism, the expression of the key genes HMGR and DXR were detected. The result showed the gene DXR expressed high in tobaccos of the both areas, and it is beneficial for the accumulation of the terpenoids substances. HMGR expressed steadily in Puge tobaccos, which showed that the dramatic decline of the carbon metabolism did not influence MVA way. HMGR gene gradually increased in Huili tobacco. The PPO activity of tobaccos was higher in Huili, so a kind of alkaloids may be synthetized more. The higher TDC activity in Puge tobaccos is in favor to the synthesis of indoles analogous alkaloids.