《植物生理学报》 2014, 50(9): 1322-1328

绿色器官衰老进程中营养物质的动员与再利用研究进展

李中朋, 蒯本科*

复旦大学生命科学学院, 植物科学研究所, 遗传工程国家重点实验室, 上海200433

通信作者：蒯本科；E-mail: bkkuai@fudan.edu.cn；Tel: 021-65642648

摘　要：

绿色器官的衰老是植株生长发育的一个内在组成部分, 其重要的生物学意义在于营养物质的动员与再利用。作为最重要的营养“源”器官, 衰老叶片中发生大规模的降解代谢活动, 由此产生的大量小分子物质, 包括糖类, 氨基酸, 核苷酸和可再生利用的矿质元素等会通过筛管转运至新生的组织器官, 即“库”器官, 特别是种子中, 为其快速生长发育提供充足的营养供应。本文主要介绍了绿色器官衰老过程中氮素的营养动员与再利用研究进展, 包括叶片中蛋白的降解和氨基酸的代谢转化, 以及筛管装载和卸载。最后, 对未来的研究方向进行了展望, 提出了作物叶片光合总量和营养物质利用效率双双趋于最大化的理想叶片衰老模式。

关键词：绿色器官衰老; 营养物质动员与再利用; 氮素动员与再利用; 理想叶片衰老模式

收稿：2014-07-21   修定：2014-08-15

资助：国家自然科学基金项目(3117021)和上海市科委重点基础研究项目(13JC1400900)。

Advances in Understanding the Process of Nutrient Remobilization during Green Organ Senescence

LI Zhong-Peng, KUAI Ben-Ke*

State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China

Corresponding author: KUAI Ben-Ke; E-mail: bkkuai@fudan.edu.cn; Tel: 021-65642648

Abstract:

Green organ senescence is an integral part of plant development, and nutrient remobilization during the process possesses a fundamental importance to nascent organ development. Leaves are major modular green organs, and therefore become the most important source organs during senescence. Massive catabolic activities result in the production of abundant small molecules including amino acid and sucrose, which are recycled from senescent leaves to nascent tissues and organs to meet the requirements of their rapid developments. In this review, we focused on the current understanding of nitrogen remobilization process, including chloroplast protein degradation and its resultant product phloem transportation. Finally, we proposed an ideal pattern of crop leaf senescence which maximizes the accumulation of photosynthetic products and the efficiency of nutrient remobilization.

Key words: green organ senescence; nutrient remobilization; nitrogen remobilization; an ideal pattern of leaf senescence