Developmental changes of plant affecting primary photosynthate distribution in rice leaves
Developmental changes of plant affecting primary photosynthate distribution in rice leaves
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DOI：
10.1007/s11099-006-0076-8
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发表时间：
2006-12
期刊：
影响因子：
2.7
通讯作者：
T. Shinano;K. Ando;K. Okazaki;M. Osaki
中科院分区：
文献类型：
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作者：
T. Shinano;K. Ando;K. Okazaki;M. Osaki
采用 14CO2 示踪技术，研究了水培水稻叶片光合产物分布调节的发育变化，并分析了调节酶、蔗糖磷酸合酶 (SPS)、磷酸烯醇丙酮酸羧化酶 (PEPC) 和丙酮酸激酶 (PK) 的活性。通过柱色谱法测定初级光合产物向糖、氨基酸、有机酸、糖磷酸盐、蛋白质和多糖的分布。第 5 叶中糖磷酸部分的相对初级光合产物分布显着大于第 6 叶。相应地，第5叶PEPC的Vmax显着高于第6叶，而其他酶在叶片之间没有检测到显着差异。结果，第5叶的SPS和PEPC的Vmax比值低于第6叶。由于第 5 叶在水稻的穗形成之前发育，因此它主要支持营养生长，而第 6 叶在穗形成之后发育，因此主要有助于生殖生长。我们得出的结论是，每片叶子的生理特性都受到发育的调节。当第6叶完全展开时（对应植物的圆锥花序萌生阶段），第5叶中~(14)C的分布模式发生了短暂的变化，表明主要参与营养发育的各个器官在一定程度上受到了从营养阶段向生殖阶段过渡时发生的全株水平的生理转变的影响。
Developmental changes of plant in the regulation of photosynthate distribution of leaves were studied in hydroponically cultivated rice by the14CO2tracer technique and analysis of the activity of the regulatory enzymes, sucrose phosphate synthase (SPS), phosphoenolpyruvate carboxylase (PEPC), and pyruvate kinase (PK). The distribution of primary photosynthates into sugars, amino acids, organic acids, sugar phosphates, proteins, and polysaccharides was determined by column chromatography. The relative primary photosynthate distribution to the sugar phosphate fraction was significantly larger in the 5thleaf than in the 6thone. Correspondingly, the Vmaxof PEPC was significantly higher in the 5ththan in the 6thleaf, while no significant differences between leaves were detected in the other enzymes. As a consequence, the ratio of the Vmaxof SPS and PEPC was lower in the 5ththan in the 6thleaf. As the 5thleaf develops before panicle initiation in rice, it predominantly supports vegetative growth, while the 6thleaf develops after panicle initiation and thus contributes mainly to reproductive growth. We conclude that the physiological properties of each leaf are regulated developmentally. When the 6thleaf became fully expanded (corresponding to the panicle initiation stage of plant), the distribution pattern of14C was transiently changed in the 5thleaf, indicating that individual organs that are mainly involved in vegetative development are affected to some extent by the whole-plant-level physiological transformation that occurs at the transition from the vegetative to the reproductive stage.