谷物胚乳淀粉体的发育及其与品质形成的关系

Amyloplasts are organelles that are responsible for the synthesis and storage of starch granules. Development and starch filling of endosperm amyloplasts affect both grain yield and starch quality. In resent years, our observations on amyloplast development and structural characteristics of various cereal species have indicated the multiple patterns of amyloplast formation and division, certain degree of independence of endosperm amyloplasts development, and the existence of amyloplast generator centers in sorghum endosperm cells..Based on our previous work, we propose to study at the subcellular level on rice, wheat, sorghum, maize and other caryopses as the experimental materials, by marking exact dates of caryopsis development, embedding caryopsis with low-viscosity resin, observing ultrastructure changes of amyloplast development under electron microscopes, separating amyloplasts from endosperm cells, analyzing both DNA of amyloplasts and the activities of the enzymes related to starch synthesis in different development days, et al. The main objectives of our research are to demonstrate: (1) patterns of emergence, division, growth and decline of endosperm amyloplasts; (2) internal and external factors that determine endosperm amyloplast development; (3) the relationship between amyloplast development and certain endosperm characteristics. .Our research results on the development patterns of cereal endosperm amyloplasts can take the investigation of endosperm development to a new level, thus, substantiating the knowledge in cell biology, morphology and anatomy, crop physiology and other fields, and providing a theoretical foundation for grain production, quality improvement, and starch industry development.

淀粉体是合成和积累淀粉的细胞器。胚乳淀粉体的发育和充实状况影响着谷物的产量与品质。近年来我们观察了多种作物的淀粉体的发育进程和结构特点，发现胚乳淀粉体的发生与分裂具有多样性；发育具有一定的自主性；高梁胚乳细胞中还有淀粉体发生中心。.本项目拟在原有工作基础上，以水稻、小麦、高梁、玉米等颖果为材料，精确标记颖果发育天数,采取低粘性树脂包埋颖果、电镜观察淀粉体发育的超微结构变化、分离胚乳细胞和淀粉体、检测发育不同天数淀粉体中DNA和与淀粉合成相关酶的活性等方法，在亚细胞水平上研究并探明：(1)胚乳淀粉体的发生、分裂、生长和衰亡的规律；(2)控制胚乳淀粉体发育的内外因素；(3)淀粉体发育与胚乳某些品质形成的关系。.探讨谷物胚乳淀粉体发育的规律,将深化胚乳细胞发育的研究,结果将充实细胞生物学、形态解剖学、作物生理学等学科知识，为谷物的生产和品质改良以及淀粉工业的发展创新理论。

谷物胚乳淀粉体的发育及其与品质形成的关系.水稻、小麦、大麦、高粱、玉米等谷物是主要的粮食作物，其胚乳淀粉是人类食粮、禽畜饲料和食品工业原料的主要来源。而胚乳淀粉体是合成贮存淀粉的细胞器。胚乳淀粉体的发育和充实状况决定着谷物的产量与品质。.本项目基本按原计划进行。种植了水稻、小麦、大麦、高粱、玉米等谷物的多种品种，在开花结实期精确标记颖果发育天数，测定颖果的生理活性和淀粉体的理化特性；对发育不同天数的颖果进行固定与包埋，用光镜和电镜观察胚乳细胞及其淀粉体发育的结构变化，在亚细胞水平上研究并探明了：(1)谷物颖果生长与胞乳细胞发育的关系；(2)胚乳淀粉体的发生、生长和衰亡的规律；(3)控制胚乳淀粉体发育的内外因素；(4)淀粉体发育与胚乳某些品质形成的关系；(5)灌浆物质进入胚乳的途径等问题。.发现:(1)淀粉体的发生与分裂具有多样性：淀粉体可以来自原质体积累淀粉后的转变；可以由类线粒体的质体积累淀粉后的转化；更多的可以通过出芽或缢缩等方式增殖。由出芽或缢缩等方式增殖可使一个淀粉体分裂成多个淀粉体。(2) 高粱胚乳细胞中有淀粉体的发生中心，由发生中心产生许多具有双层被膜的质体管，淀粉体在质体管基质中形成。 (3)不同谷物，或同一谷物的不同部位，以及同一部位的发育不同时期，淀粉体形态和大小都有差异。(4) 胚乳淀粉体的发育状况决定淀粉体的形态和胚乳的性状。.本项目至今发表论文30篇，出版了关于谷物胚乳发育的专著1部，培养研究生7人。研究成果充实了细胞生物学、形态解剖学、作物生理学等学科知识，为谷物的生产和品质改良以及淀粉工业的提供新的理论。