【作者】 陈义芳；

【导师】 王忠；

【作者基本信息】 扬州大学 ， 植物学， 2003， 硕士

【摘要】 本试验选择粒重差异显著的四个水稻品种，用称重法测定了颖果的鲜干重，采用微孔滤膜抽滤酶解细胞悬浮液的方法研究了胚乳细胞增殖动态，用光镜和电镜观察了颖果的结构及其胚乳细胞的充实情况，并鉴定了颖果中某些生理活性的变化，主要结果如下： (1)就同为大粒或小粒而言，籼稻发育快于粳稻，且籼稻前期发育快，干物质积累多；粳稻发育慢但持续时间长，最终籽粒较籼稻饱满；同一亚种间，小粒品种发育时间短，大粒品种发育时间长，最终颖果干重大于小粒品种。 (2)胚乳细胞数均在花后10～15d左右确定，且大粒品种的胚乳细胞数、胚乳干重及单个胚乳细胞重均高于小粒品种；其长、宽、厚度也都大于小粒品种。 (3)籼稻颖果淀粉积累快，脱氢酶活性维持较高水平的时间较短；大粒品种颖果充实时间相对较长，淀粉积累多，脱氢酶活性维持高水平的时间长。 (4)粳稻果皮细胞中淀粉粒含量多，而且持续时间长；而籼稻在花后10d时果皮细胞已经开始收缩；大粒品种与小粒品种相比，小粒品种的果皮细胞收缩的时间要早与大粒品种。 (5)籼稻与粳稻相比，籼稻外层胚乳细胞在花后7d已转化成糊粉层细胞，而粳稻要到花后10d才转化成糊粉层细胞。 (6)大粒品种垩白粒率高，具有腹白和心白，而小粒品种的胚乳细胞小而致密，几乎不形成心白和腹白。更多还原

【Abstract】 Four rice varieties, whose grain weights were remarkably different, were used in this experiment to compare their caryopsis development. Their differences of caryopsis fresh and dry weights were compared by weight method, proliferation dynamics of endosperm cells was studied by the method that the enzymolyzed cell suspension was pumped to filtrate through a microporous filter film, structures of caryopsis and fill of endosperm cells were observed with light and electron microscopes, and some activity changes in some biophysical aspects were identified. The main results were as follows:(1) When they were all big or small grain, the caryopsis development in indica was fast, and the accumulation of dry matter was more at early stage; The development was slow and lasted long time in japonica rice; When they were the same subspecies, the development of big grain varieties was slower than the small, and finally the dry weight of caryopsis was heavier;(2) In four rice varieties, the number of endosperm cells was no changc10-15days after flowering, and in the big grain varieties, the number of endosperm cells, dry weight of endosperm and each endosperm cell were higher than the small, the length, width and thickness all exceeded the small;(3) The accumulation of starch in indica rice was faster and the time of the activity of dehydrogenase with maintaining higher lever was shorter than japonica rice; The development of caryopsis of the big grain lasted long time and a lot of starch were accumulated and the time of the activity of dehydrogenase with maintaining higher lever was longer than the small grain;(4) There were a lot of starch grains in the pericarp cells in japonica rice and these pericarp cells could be kept perfectly for a relative long time; In indica rice, the pericarp cell began to contract 10 days after flowering; Compared the big grain with small grain, the contraction of pericarp cells in the small grain was faster;(5) Compared indica with japonica rice, the outer layer endosperm cells in the indica transformed aleurone layer cells 7 days after flowering; But in the japonica these cells transformed aleurone layer cells 10 days after flowering;(6) The chalky rice percentage was high in the big grain varieties , and there were chalkiness in the center and belly of the caryopsis, the endosperm cells were small and close in the small grain, and there was hardly any chalkiness.更多还原