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莲胚子叶细胞中质体的产生从受精后的4d左右一直延续到21d左右。质体的分裂是质体数目增加的一种方式。子叶细胞在发育阶段Ⅰ,即分生组织细胞中前质体大量出现,体积小,多为变形虫状,大量的位于细胞的外围。在电子密度低的区域能观察到前质体的纤维丝。从发育阶段Ⅱ(液泡化时期)一直到阶段Ⅲ中期(细胞处于功能期,物质合成与积累时期),质体在发育中出现一些片层结构和管状复合体,这时淀粉粒开始沉积,同时在淀粉质体的膜结构和基质中常能观察到像核糖体的颗粒。在受精后的15d左右,子叶细胞中质体开始大量合成并积累淀粉。与此同时,淀粉体DNA开始出现,子叶细胞发育到授精后的18-22d时,是淀粉质体DNA复制的盛期。23d后,部分淀粉体显DNA拟核区域,有的出现多个DNA拟核区,这时淀粉体中有大量的蛋白质和蛋白块积累,一般沉积在质体的内膜周围。在部分质体中同时能观察到DNA区域、蛋白质的积累和淀粉部分的存在。约在受精后20d,淀粉体核糖体的结构已清晰可辨。在发育阶段Ⅲ的后期,质体周围的基膜结构和核糖体颗粒已经观察不到了。淀粉质体是个半自主性的器官,它有自己的DNA和RNA,有蛋白质合成系统的核糖体
The production of plastids in the lotus leaf cotyledon cells continued around 4 days after fertilization until around 21 days. Plastid division is a way of increasing the number of plastids. Cotyledon cells in the developmental stage Ⅰ, that is, a large number of meristematic cells in the pre-body mass, small size, mostly amoeba, a large number located in the periphery of the cell. Precursor filaments were observed in areas of low electron density. From the developmental stage II (vacuolar stage) to the middle of stage III (the cell is in the functional phase, the stage of material synthesis and accumulation), plastids show some lamellar structures and tubular complexes in development, at which point the starch grains begin to deposit and at the same time Ribosome-like particles are often observed in the membrane structure and matrix of amyloplasts. After about 15 days after fertilization, plastids in cotyledon cells began to synthesize and accumulate starch. At the same time, amyloid DNA began to appear, cotyledon cells developed to 18-22d after insemination, is the peak of the replication of the starch plastid DNA. After 23 days, some amyloids showed DNA nucleation sites, and some appeared multiple DNA nucleation sites. At this time, there were a large number of protein and protein accumulations in the amygdala, which were usually deposited around the intima of plastids. In part of the plastid at the same time can be observed in the DNA region, the accumulation of protein and the presence of starch parts. About 20 days after fertilization, the structure of amyloplast ribosome has been clearly identifiable. At the end of developmental stage III, the basement membrane structure and ribosome particles surrounding the plastids have not been observed. Starch plastid is a semi-autonomous organ that has its own DNA and RNA, a ribosomal protein synthesis system