Physiological Identification of Salt Tolerance in Transgenic Tobacco Expressing Genes Related to Plant Trehalose Metabolism

According to the previous results of the molecular identifications of transgenic tobaccos, the representative individuals, CK (non-transgenic), 121 (with pBI121 vector), 1285 (with pGSA1285 vector), T4 (with gene of trehalase, TRE), SI, S5 (with gene of trehalose-6-phosphate synthase, TPS), P3 (with gene of trehalose -6 - phosphate phosphatase, TPP), a3 (with anti-TRE), i2 (with RNAi-TRE), were selected for identification of salt tolerance, and the chlorophyll content, Malondialdehyde (MDA), relative conductivity, catalase, proline and peroxidase (POD) have been measured after salt stress during this experiment. The results showed that the transgenic tobaccos with anti-TRE and RNAi-TRE grew better than other individuals under 100 mmol/L NaCl salt stress conditions, T4´s MDA was observably higher than that of other individuals and i2´POD was markedly higher than other plants. These indicate that through application the antisense RNA and RNA interference technology to trehalase gene, it is possible to make the receptor trehalose metabolism changes. The weakening of expression of trehalase gene led to the accumulation of trehalose content and the enhancement of salt tolerance in the transgenic tobaccos.