【作者】 袁莉民；

【导师】 杨建昌； 张建华；

【作者基本信息】 扬州大学 ， 作物栽培学与耕作学， 2006， 博士

【摘要】 研究稻米形成(受精子房的发育充实)过程中米粒的形态结构与生理生化的变化,对揭示粒重和米质形成的机理有重要意义。本研究从籽粒灌浆、胚乳的形态发育、粒重形成、米粒密度、胚乳淀粉结晶度、淀粉合成关键酶的活性等方面研究了稻米形成的特点及其在品种间与粒位间差异,研究了温度、土壤水分及氮肥管理对水稻光合特性、胚乳发育和米质的影响。主要结果如下:1.不同基因型水稻籽粒灌浆特性与胚乳淀粉结构以籼稻、粳稻、糯稻和杂交稻等不同基因型水稻为材料,研究了籽粒灌浆特性、胚乳结构的形成在不同基因型间的差异与分布特点。结果表明,⑴不同基因型水稻灌浆强度差异明显,以杂交稻的灌浆速率最大,籼稻次之,粳稻最小,糯稻居于籼稻和粳稻之间;杂交稻的活跃灌浆期最短,糯稻次之,粳稻最长,籼稻居于粳、糯稻之间。籽粒灌浆基本遵循早开花的籽粒,其平均灌浆速率、最大灌浆速率较大、达到最大灌浆速率的时间和活跃灌浆期较短、粒重较高的规律。⑵强势粒约在花后15d粒长和粒宽发育基本完成,粒型基本形成,粒厚增长持续时间长。弱势粒的粒长、粒宽和粒厚发育滞后于强势粒10d左右。⑶灌浆期发育米粒密度的高低排序25d后不再按颖花开花顺序,但较强势籽粒的密度较高,接近最大密度值的时间一般为花后20～25d,一般比弱势籽粒早10d,这与强势籽粒活跃灌浆期短相相吻合。愈是迟开花籽粒,发育米粒密度的差异愈大。2个糯稻品种和2个杂交稻品种穗上一次枝梗不同粒位各籽粒比2更多还原

【Abstract】 It has great significance in understanding the mechanism in the formation of grain weight and quality of rice to elucidate the changes in the morphological structure, physiology and biochemistry of grains during the grain formation (the development and filling of a fertilized ovary). This study investigated the characteristics of grain formation and their differences among rice genotypes and grain positions within a panicle from the aspects of grain filling,endosperm development, kernel density, crystal percentage of endosperm starch and activities of the enzymes associated with starch synthesis. The effects of low and high temperatures at different grain filling stages, soil moisture and nitrogen (N) management on photosynthetic characters, endosperm development and grain quality were also investigated .The main results were as follows:1. Grain filling characteristics and endosperm structures of different rice genotypes With indica and japonica cultivars, including glutinous rice and hybrids, as materials, the differences in grain filling and the formation of endosperm structures among the genotypes were investigated. The results showed that (1) Grain filling rates varied significantly with rice genotypes,with the greatest for hybrids, the second for indica, and the least for Japonica. The grain-filling rate of glutinous rice was between indica and japonica. The earlier the spikelet flowered, the greater the mean and maximum grain filling rates, the shorter the active grain filling period and the time reaching the maximum grain filling rate, and the greater the grain weight. (2) The development of length and width for a superior grain, was completed about 15 days after更多还原