Photosynthetic Characteristics of Transgenic Rice with PEPC+PPDK Gene

【Objective】The aim of this paper is to study photosynthetic characteristics of PEPC+PPDK transgenic rice for demonstrating that ATP is the key factor enhancing the photosynthetic capacity in transgenic rice with C4 genes.【Method】 With the untransformed rice and PEPC+PPDK transgenic rice as the materials, PCR test and the activity of C4 photosynthetic enzymes were conducted. After the ATP treatment , the light, temperature-photosynthetic curves, the parameters related to the metabolism of active oxygen and the component factors of yield were analyzed【.Result】The untransformed rices posses all the C4 photosynthetic enzymes but their activities are very low. The PCR test indicated that PEPC and PPDK gene from maize were transformed into common rice. The activities of the C4 enzymes in PEPC+PPDK transgenic rice were highly expressed. Under the conditions of high photon flux density and high temperature, the photosynthetic rate of PEPC+PPDK transgenic rice after the ATP treatment increased by 17% and 12%, respectively, compared with the controle without ATP treatment. The resistance of PEPC+PPDK transgenic rice against photooxidation was further enhanced under the photooxidative conditions. The yield of PEPC+PPDK transgenic rice were also increased by 15%. 【Conclusion】 The photosynthetic productivity of PEPC+PPDK transgenic rice after the ATP treatment was enhanced, demonstrating that ATP is the key factor for designing the C4-like rice.