Oogenesis in Propylea japonica (Thunberg) | 龟纹瓢虫（Propylea japonica (Thunberg)）卵子发生的组织学研究

Chinese. 系统观察龟纹瓢虫（Propylea japonica (Thunberg)）卵子发生过程，为进一步了解龟纹瓢虫的生殖生物学奠定基础。对处于不同发育时期的龟纹瓢虫卵巢做石蜡切片，光镜下观察其卵子发生过程。第1阶段，在卵原区可见分化的卵母细胞和滋养细胞，卵母细胞正进行减数第一次分裂；第2阶段，卵母细胞向生长区移动，细胞体积逐渐增大，细胞核形成胚泡，前滤泡细胞逐渐分布于卵母细胞之间；第3阶段，卵母细胞体积明显增大，呈圆球形，前滤泡细胞分化形成滤泡细胞，呈单层扁平细胞包围卵母细胞，胚泡移动到卵母细胞的一侧；第4阶段，滤泡细胞呈立方形，此时卵母细胞仍然通过营养索与滋养细胞相连；第5阶段，卵母细胞不再与滋养细胞连接，滤泡细胞由立方形变为扁平状，在卵母细胞质的边缘处出现细小的卵黄颗粒；第6阶段，卵黄颗粒逐渐充满整个卵母细胞，胚泡退化；第7阶段，卵母细胞表面形成卵黄膜和卵壳，滤泡细胞逐渐与卵母细胞分离，卵母细胞发育为成熟的卵子。龟纹瓢虫卵子发生过程可明显划分为卵母细胞分化期、卵母细胞生长期、卵黄形成及卵子成熟期3个时期，并可进一步分为7个阶段。

English. The study was intended to observe the oogenesis of Propylea japonica (Thunberg) and to provide theoretical basis for reproductive biology of Propylea japonica. Ovaries in different developmental stages were studied by paraffin sectioning. (1) Oocytes and nurse cells were located in the germarium; first meiotic division occurred at this stage; (2) Oocytes grew in size and moved towards the vitellarium. The nucleus of the oocyte transformed into germinal vesicle. And the pre-follicle cells were located between the oocytes; (3) Oocytes became globosity and the monolayer follicle cells were flat surrounding the oocyte, the germinal vesicle moved into the periplasm; (4) Follicle cells became cubic in shape, and the nurse cells still connected with the oocytes by the nutritive cord at this stage; (5) The nutritive cord disappeared, and the follicle cells became flat and some yolk granules appeared on the edge of cytoplasm; (6) Ooplasm was gradually filled up with yolk granules, and the germinal vesicle breakdown occurred; (7) The vitellin member and egg shell formed and encircled the oocyte. Oogenesis in the adult stage of Propylea japonica (Thunberg) could be divided into 3 phases and 7 stages.