Stress-inducible Promoter Regulates The Expression Of Mnsod Gene Into Rice

To develop drought-tolerant rice (Oryza sativa L. cv. Zhonghua 11) plants, a pea manganese superoxide dismutase (MnSOD) was introduced into chloroplasts under the control of an oxidative stress-inducible SWPA2 promoter by Agrobacterium-mediated transformation. The proper expression of the foreign MnSOD in transgenic rice plants (T1) was revealed under drought stress induced by polyethylene glycol (PEG) 6000. After PEG treatment transgenic (T1) leaf slices showed reduced electrolyte leakage when exposed to methyl viologen (MV) at 5 (M and 0 (M as compared to those of wild type (WT), suggesting that transgenic plants were more resistant to MV- or PEG-induced oxidative stress. Transgenic plants (T1) also exhibited a reduced injury by increased net photosynthetic rate under PEG treatment. Our data suggest that SOD is one of the critical components of ROS scavenging system in plant chloroplasts and high expression of SOD can improve drought tolerance in rice.