| Rice(Oryza Sativa L.) is one of the main resources of cereal grown in China and even in the Asian. It plays a very important role in food supply. Endosperm is the most primary part of the rice grain that can be eaten, so the developmental pattern of endosperm influence the grain quantity and quantily directly. Starch is both the major component of the yield in the world's main crop plants and an important raw material for many industrial processes.In this thesis, we report the structural and functional research about nucellar cells PCD, endosperm cells construction, and amyloplasts initiation and development during the development of the endosperm of the rice. The main research results were as followed.1.Construction of the rice endosperm cells Cellularization of the free-nuclear endosperm was initiated about 2 days after pollination(DAP) with the form of the peg-like anticlinal ingrowths on the central cell wall. These ingrowths extended into the lumen of central cell and fused with the linear endoplasmic reticulum(ER) by many electron-dense vesicles. Periclinal walls were formed by two mechanisms: (1) formation of the phragmoplasts followed the kynokinesis, (2) fusion of the free-edges of the opposing anticlinal walls. It was speculated that the electron-dense vesicles had three resources. From the Golgi apparatus, ER or degenerated nucellar cells which were transported through the ingrowths of central cell wall. By the means of cytochemistry of ultrastructure, We observed the location change of the AcPase. During the proceeding of the cellularization, the new-formed cell walls had distinct aggradation of the AcPase, but on the cell walls which were formed a longer time ago, we could not observe the aggradation of the AcPase.2. The resource and development of amyloplasts in theendosperm cells The amyloplasts of rice were compound starch granules. We observed that the amyloplasts could be initiated not only from the plastids, proplastids and amyloplasts, but also from the mitochondria. They appeared in the endosperm cell after 60 hours after pollination, and propagated by the formation of gemma or by contraction in the middle before splitting. The ultrastructural location of AcPase suggested that the nucleus and other cell apparatus were degenerated in the mature endosperm cells, which were filled with amyloplasts and protein bodies. So they showed another kind of phenomena of PCD.The compare of the starch granules of different stage of development showed that the 3-12 days after pollination was the fastigium of the development of the starch granules. During this period, the augmentation of the diameter of the starch granules was approximate the pattern of beeline. But after 12 DAP, the diameter of the starch granules maintained at a invariable level. The shape of the starch granules in the medial region of the endosperm was different from the ambient region of that. Most of the starch granules in the medial region of the endosperm was polyhedral, crystalline and compact arranged; but the starch granules in the ambient region were almost ball shape, loose arrangement.3. The proceeding of Programmed Cell Death (PCD) of nucellar cells during the development of the endosperm PCD of nucellar cells initiated in 2 days after pollination (2DAP). By the means of ultrastructure cytochemistry, we researched the variation of AcPase (Acid phosphatase) in nucellar cells. During the proceeding of PCD, AcPase was located on the nuclear membrane, nucleus, cytoplasma membrane, ER membrane, Mitochondria membrane, and cytoplasm in respectively. At the same time, it accompanied with phenomena of apoptosis which included, chromatin condensation and margination, cytoplasm vacuolation, mitochondria swelling and alveolation. endoplasmic reticulum(ER) cisterna swelling, cytoplasma membrane and cell wall separation, cell apparatusesdegeneration, apoptosis bodies produce, which contained the degenerated material from cell apparatuses and cell nucleus. At last, the cell walls were broken, and apoptosi...
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