文献类型： 会议论文

第一作者： D-M Jiao

作者： D-M Jiao ¹ ; X-Q Huang; X Li; W Chi; T-Y Kuang; Q-D Zhang; MSB Ku;

作者机构： 1.Institute of Agrobiological Genetics and Physiology, Jiangsu Academy of Agricultural Sciences, Nangjing 210014, China

关键词： phosphoenolpyruvate carboxylase (PEPC);photosynthetic characteristics;transgenic rice

会议名称： Proceedings 12th international congress on photosynthesis

主办单位：

页码： S33-005/1-S33-005/4

摘要： More than 95 percent of the terrestrial plants, including many agronomically important crop species such as rice, assimilate carbon through the C_3 pathway of photosynthesis. Under current atmospheric conditions, O_2 reduces the photosynthetic capacity by as much as 30-40 percent. If these plants were under drought and high temperature, high light intensity conditions, the photosynthetic capacity would decline further (Ku et al. 1999). There existed C_4 photosynthetic pathway in some plants such asmaize, PEPC in the mesophyll cells has a high affinity for the substrate, bicarbonate, which is not inhibited by O_2 and has a function of concentrating CO_2. Therefore the C_4 plant maintained higher photosynthetic efficiency. It was discovered that C_4 photosynthetic enzymes might also play important roles in plant defense responses to biotic and abiotic stress (Schaf et al. 1995). Over a long period of time, severalattempts to incorporate C_4 traits into C_3 crops had been made, but there was no striking achievement. Some notable progress has been made lately (Brown et al. 1986, 1993; Jiao et al.1991). Rishishi et al. (1988) obtained some C_4-like plants derived from a cross Atriplex rosea (C_4) X Atriplex. Putula (C_3) X Atriplex.rosea (C_4), which indicated that C_4 photosynthetic genes could be expressed in C_3 plants by genetic manipulation within a genus. But the conventional hybridization in the same family between genus such as between C_4 (maize) and C_3 (rice) crop can't still bring intoeffect in crossbreeding. In recent years, with the rapid development of transgenic technology, the intact genes encoding maize PEPC, PPDK, NADP-ME, were introduced into the C_3 rice crop by Agrobacterium-mediated transformation system, and had obtained transgenic rice plants with high-level expression (Agarie 1998, Matsuoka et al. 2000), Especially for PEPC transgenic rice, the transgenic plants exhibited reduced O_2 inhibition of photosynthesis and the grain yield per-plant increased by 10-30 percent (Ku et al. 1999), which demonstrated the broad prospects for improving crop photosynthetic productivity by genetic engineering. However, the characteristics of photosynthetic physiology of transgenic rice have not been systematically reported. In this paper, the characteristics of CO_2 assimilation of photosynthesis and .chlorophyll fluorescence and the performance of membrane-lipid peroxidation in C_4 photosynthetic enzyme-transgenic rice were studied to provide experimental evidences for enhancing photosynthesis capacity of rice and to open up a new approach to physiological breeding.

分类号： Q94