不同氮素水平下水稻生育后期叶片和籽粒的蛋白质组学

以超级杂交水稻“两优培九”为试验材料，运用蛋白质双向电泳技术研究了水稻生育后期不同氮素水平下（正常供氮水平的1/2，20 mg·L^-1；正常供氮水平，40 mg·L^-1；正常供氮水平的2倍，80 mg·L^-1）叶片和籽粒蛋白质组水平的变化，并鉴定分析了其差异蛋白质点（共鉴定出16个叶片蛋白质、9个弱势粒蛋白质、4个强势粒蛋白质）的生物功能.结果表明：生育后期氮素是通过影响与光合有关的酶的活化、CO₂的活化及光系统单位和电子传递链构成来影响和调节植物的光合作用；氮素可促进弱势粒中与能量合成和生长相关酶的表达；高氮水平不利于强势粒淀粉的合成，但充足的氮素对水稻物质累积及代谢具有重要作用.因此，在生育后期合理运用氮肥对提高水稻剑叶光合性能、增强源的功能、延缓功能性早衰及强化籽粒灌浆具有积极作用.

Proteomics of rice leaf and grain at late growth stage under different nitrogen fertilization levels

Taking super-rice Liangyoupeijiu as test material, and by the method of two-dimensional gel electrophoresis (2-DE), this paper studied the changes in the leaf and grain proteomics of the variety at its late growth stage under different levels of nitrogen fertilization (1/2 times of normal nitrogen level, 20 mg·L^-1; normal nitrogen level, 40 mg·L^-1; 2 times of normal nitrogen level, 80 mg·L^-1), with the biological functions of 16 leaf proteins, 9 inferiorgrain proteins, and 4 superior grain proteins identified and analyzed. Nitrogen fertilization could affect and regulate the plant photosynthesis via affecting the activation of photosynthesis-related enzymes and of CO₂, the light system unit, and the constitution of electron transfer chain at the late growth stage of the variety. It could also promote the expression of the enzymes related to the energy synthesis and growth in inferior grains. High nitrogen fertilization level was not beneficial to the synthesis of starch in superior grain, but sufficient nitrogen supply was still important for the substance accumulation and metabolism.Therefore, rational nitrogen fertilization could increase the photosynthesis rate of flag leaves, enhance the source function, delay the functional early ageing, and promote the grain-filling at late growth stage.