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鉴测了粳稻胚的发育进程及不同分化发育时期中DNA、RNA、蛋白质、淀粉含量和鲜重、干重、细胞数的变化。 开花后6～13天(胚分化第一到第四叶原基期间)胚细胞数增加时,DNA、RNA含量迅速上升。此后细胞数和DNA、RNA含量都趋于稳定,但RNA在18～25天再次增长。每胚蛋白质和干重基本上随RNA含量相应地变化。 每毫克胚于重的核酸和蛋白质含量在13天出现明显的转折。平均每细胞的DNA含量在整个发育期保持稳定,RNA第一阶段的增长只持续到分化完成的前夕,而蛋白质在25天以前一直增加。 胚内淀粉的累积在整个胚形成期呈现三段斜率不同的直线。以单位干重表示时则在8天左右和21天出现两个高峰,先于RNA和蛋白质两次积累的高峰。 在大分子物质的变化与胚胎发育进程相互关系并与籼稻比较的基础上,将稻胚发育划分为原胚期、分化期、成熟期和休止期。
The development of japonica rice and the changes of DNA, RNA, protein, starch content, fresh weight, dry weight and cell number in japonica rice embryos were investigated. When the number of blast cells increased from 6 to 13 days after flowering (the first to the fourth leaf primordia were differentiated), the content of DNA and RNA rapidly increased. Since then the number of cells and DNA, RNA content tends to stabilize, but the RNA again increased in 18 to 25 days. Basically, each embryo protein and dry weight will vary with RNA content. Significant turning points occurred in 13 days for each mg of embryo-heavy nucleic acid and protein content. The average DNA content per cell remained stable throughout the developmental phase, with the first phase of RNA growing only on the eve of the completion of differentiation and the protein increasing all the way up to 25 days. The accumulation of starch within the embryo presents three straight lines with different slopes throughout the embryogenesis. When expressed in units of dry weight, there were two peaks in about eight days and twenty-one days, preceded by two peaks of RNA and protein accumulation. On the basis of the correlation between the change of macromolecules and the process of embryo development and comparison with indica rice, the embryo development was divided into embryo stage, differentiation stage, mature stage and resting period.