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本文通过透射电镜对水稻受精前胚囊中央细胞发育过程中超微结构的变化进行观察。结果表明，八核胚囊形成后很快就进行细胞化形成7个细胞，其中刚形成的中央细胞由1个大液泡、2个极核（珠孔端和合点端各1个）和一些含有丰富细胞器的胞质组成。中央细胞以后的发育主要是极核的发育和极核周围胞质的变化。极核发育经历以下过程：a．2个核都膨大呈“椭圆”形。核周围胞质呈不对称分布。b．2个核分别向胚囊中央移动并相互靠近。之后2个极核调整排列方式，由纵排（即与胚囊纵轴平行）变成横排。此时期有细胞质“桥”联结珠孔端卵器、2个极核和合点端反足细胞器。c．横排的极核移向卵器，并排列于卵细胞之上。此时胚囊未明显膨大，但极核相靠近的两边核膜有许多处已形成“融合桥”，核周围的胞质也起较大的变化，如质体内淀粉消失和光面内质网增加等。极核进一步发育直至胚囊成熟期间，极核排列方式及其周围胞质组成未观察到明显的变化，但胚囊体积明显增大。
In this paper, the changes of ultrastructure of embryo sac central cell during fertilization before rice fertilization were observed by transmission electron microscopy. The results showed that eight nucleated embryo sac cells formed 7 cells soon after their formation, of which the newly formed central cells consisted of one large vacuole, two polar nuclei (one perovascular and synaptic end) Enriched organelles cytoplasmic composition. After the central cell development is mainly the development of polar nuclei and polar nuclei around the cytoplasm changes. Polar nuclear development goes through the following process: a. 2 nuclei are swollen in an “oval” shape. The cytoplasm around the nucleus is asymmetrically distributed. b. The two nuclei moved to the center of the embryo sac and approached each other. After 2 polar nucleus to adjust the arrangement, from the vertical row (that is, parallel to the longitudinal axis of embryo sacs) into a row. This period of cytoplasmic “bridge” junction of the archegonial oviposit, two polar nuclei and junction point antipodal organelles. c. Transversal polar nucleus moved to the egg, and arranged above the egg cells. At this point, the embryo sac was not obviously enlarged, but many nuclear membranes on both sides of the polar nucleus had formed “fusion bridges”, and the cytoplasm around the nucleus also changed greatly, such as the disappearance of starch in the plastids and the increase of smooth endoplasmic reticulum Wait. During the further development of polar nuclei until embryo sac maturation, no significant changes were observed in the arrangement of polar nuclei and the surrounding cytoplasm, but the volume of embryo sac increased significantly.