Abstract: NC 89 tobacco plants were transformed via Agrobacterium tumefaciens. PCR and RT-CR indicate that the foreign gene KatB of Pseudomonas aeruginosa has been integrated into the genome of tobacco. Stress resistance tests were carried out under water stress, 300 mmol/L NaCl stress and 0.3 mmol/L H₂O₂ stress. The results proved that the physiological indexes including leaf relative water content, MDA activity, relative conductivity and maximum photochemical yield of PSII of KatB tobacco were evidently higher than those of wild tobacco on the 13th day of water stress, 20th day of 300 mmol/L NaCl stress and the 33rd day of 0.3 mmol/L H₂O₂ stress. The stress resistance of transgenic plants was high, which testified that there is a good application prospect of KatB gene in stress resistance of genetic engineering.

Key words: Pseudomonas aeruginosa, KatB gene, tobacco, stress resistance