水稻胚乳组织的结构观察

【目的】阐明水稻糊粉层细胞、亚糊粉层细胞与中心胚乳贮藏细胞的结构特性。【方法】采用光镜、透射电镜与扫描电镜对水稻胚乳组织进行观察研究。【结果】糊粉层细胞分化过程中,大液泡变成小体积蛋白贮存液泡,蛋白贮存液泡又转变成糊粉粒。颖果背部比腹部有更多层糊粉层,但背部糊粉层细胞内糊粉粒的形成与积累速度却较慢。亚糊粉层细胞起初含有一些脂质体,后来脂质体消失,而其内部淀粉体与蛋白体逐渐增多。中心胚乳贮藏细胞含有淀粉体与蛋白体,蛋白体以液泡型蛋白体为主,它们可以相互融合而变大。中心胚乳贮藏细胞内的淀粉积累速度明显快于亚糊粉层细胞内的。成熟颖果的中心胚乳贮藏细胞内淀粉体最为密集,背部和侧部的亚糊粉层细胞内淀粉体排列较疏松,腹部的亚糊粉层细胞内淀粉体最为稀疏。【结论】水稻颖果背部与腹部的糊粉层细胞和亚糊粉层细胞的结构差异可能与养分吸收与转运有关;中心胚乳贮藏细胞内淀粉体发育速度快于亚糊粉层细胞。

Structure Observation of Rice Endosperm Tissues

【Objective】 The objective of this research was to clarify structural characteristics of aleurone cells, sub aleurone cells and central starchy endosperm cells. 【Method】 We observed and investigated rice endosperm using a light microscopy, a transmission electron microscopy and a scanning electron microscopy. 【Result】 During the differentiation process of aleurone cells, the large vacuoles were transformed into protein storage vacuoles of small volume and protein storage vacuoles were transformed into aleurone granules. There were more layers of aleurone cells in the dorsal part than in the ventral part of caryopses. However, the formation and accumulation rate of aleurone granules was slower in aleurone cells of the dorsal part of caryopses. Sub aleurone cells initially included some lipid bodies, and later lipid bodies disappeared and amyloplasts and protein bodies in them increased gradually. Central starchy endosperm cells included amyloplasts and protein bodies. Vacuolar protein bodies occupied the major part of total protein bodies and they could fused with one another to be larger. Starch accumulation rate of central starchy endosperm cells was evidently quicker than that of sub aleurone cells. In mature caryopses, amyloplasts were very dense in central starchy endosperm cells, amyloplasts were sparser in sub aleurone cells of dorsal and lateral parts of caryopses and amyloplasts were sparsest in sub aleurone cells of the ventral part of caryopses. 【Conclusion】 Structural differences of aleurone cells and sub aleurone cells in dorsal and ventral parts of rice caryopses might be related to nutrient absorption and translocation. Developmental rate of amyloplasts in central starchy endosperm cells was quicker than that in sub aleurone cells.