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通过树脂半薄切片和扫描电镜技术对叶籽银杏(Ginkgo biloba L.var.epiphylla)叶生胚珠和正常胚珠授粉期的发育过程进行了观察比较。结果发现:授粉前,正常胚珠各组织已分化完全,珠被迅速生长,在珠心顶端逐渐靠拢;而叶生胚珠此时没有珠托和珠心分化,仅有脊状的突起,主要靠突起内的维管束供给营养,随着突起不断发育,有栅栏组织和海绵组织的分化。授粉期,正常胚珠有珠心组织分泌的授粉滴和珠心发生程序性死亡形成的贮粉室;而叶生胚珠未发现授粉滴的存在,已有珠心和珠被的分化,珠孔呈喙状,珠孔道伸长,但在珠孔道的下方没有发生细胞的退化,因此不能形成贮粉室。授粉后,叶生胚珠和正常胚珠进入雌配子体游离核阶段。与正常胚珠相比,叶生胚珠外观形态体积明显偏小,呈不对称发育。对叶籽银杏败育的机理进行了讨论。
The development of leaf primordial and normal ovules of Ginkgo biloba L.var.epiphylla was observed by semi-thin sections and scanning electron microscopy. The results showed that: before pollination, the normal ovule tissues had completely differentiated and the beaded rapidly grew, and gradually moved closer to the top of the rosette; while the leaf ovule did not differentiate between the beads and the beaded heart, only the ridge-shaped protuberance mainly relied on the protuberance Within the vascular bundles provide nutrition, with the continual development of the palisade tissue and sponge tissue differentiation. In the pollination stage, the normal ovules were pollinated by nacre tissues and stored in the nodules. The pollen grains formed by programmed cell death were not found in the ovules of Ophiopogon japonicus. , The peritoneal tunnel is elongate, but no cell degradation occurs under the peritoneal tract and thus can not form a poultice chamber. After pollination, leaf ovule and normal ovule enter female gametophyte free nucleus stage. Compared with the normal ovules, the morphology of the ovules of oviparous leaves was obviously smaller than that of normal ovules. The mechanism of abortion of leaf seed ginkgo was discussed.