Oxidative responses in transgenic ‘KDML105’ rice Oryza sativa L. overexpressing OsCaM1-1 against drought stress

Abstract

The OsCaM1-1 is a rice calmodulin protein which transduces Ca2+ signals to their target protein that is important to regulate cellular and physiological responses. Drought stress is the one of essential environmental stresses that affected the crop by changing in morphological, physiological, and biochemical direction tactics of plants. In this study, the effect of drought stress on growth and antioxidant system in the transgenic rice overexpressing OsCaM1-1 gene was investigated and compared to the control and wild type KDML 105. The overexpression of OsCaM1-1 in transgenic rice could increase plant tolerance to drought stress, the results showed the greater increase in the relative growth rate, the relative water content, photosynthetic pigment contents, K+/Na+ ratio, and Ca2+/Na+ ratio, besides, presented the better increase in DPPH scavenging rate, the osmoprotectant accumulation (such as proline and soluble sugar), and activity of superoxide dismutase, peroxidase, and catalase, while malondialdehyde content and % electrolytic leakage were lower than the control and wild type plants. These results indicated that the overexpressing OsCaM1-1 in transgenic rice probably improved antioxidant system under drought stress.