毕业论文移动版

摘要观察研究银杏繁殖胚珠-种子形态结构和发育，与其种子萌发特性，给有关研究和实际生产应用提供新的参考资料。为了观察分析银杏胚珠-幼种子发育特点和形态结构，包括成熟种子的肉质外种皮对萌发的影响，以及是否还有胚后熟的现象，使用室外实地、实体解剖镜和观察石蜡切片显微镜，以及种子的萌发实验的方法得以验证。最终得出以下结论，种子的种腔是由胚珠上半部的胚珠腔直接发育而来的，并且具有一定的连续性。棕褐色薄膜层是存在于种子上部的种腔与胚乳之间的，它是来自残留的珠心层而并不是内珠被。幼种子上半部膨大部位是内种皮且含储水组织，在种子成熟过程中逐渐消失。其上部膨大部位，在横切面上，平列成两瓣，其间是隙缝状种腔。此外，具有胚的成熟种子大多数能萌发，个别无胚种子和有胚种子会发霉腐烂；胚的后熟作用也不明显并且胚的萌发明显受到肉质外种皮的抑制作用。72117

该论文有图23幅，表2个，参考文献20篇。

毕业论文关键词：银杏  发育  胚珠  外种皮  萌发  解剖  繁殖器官  种子

Characteristics of The Development of Ovule-Seeds and Germination of Seeds of Ginkgo biloba L。

Abstract To observe and understand the features of the morpho-structures and development of ovule-seeds, and germination of seeds of Ginkgo biloba L。, provide new references for the relevant researches and practical application。 Through the observation in the outdoor spot, and with the indoor stereoscope and the light microscope with the method of paraffin section , and the seed germination experiment, they were observed and analysed, the morpho-structures and development of the ovules and young seeds, and the effect of the fleshy testa of mature seeds on the germination, and whether there is a phenomenon of later-ripening embryo。 The results showed that the ovule-cavity in the upper part of ovule directly and continuously developed into the seed-cavity。 Brown thin membrane between the seed cavity and the endosperm inside the upper part of the seed, was derived from the residual nucellus layer rather than the inner integument。 The upper swelling part of the young seed was the water storage tissue of the inner seed coat, which was gradually lost in the process of the seed maturation, and which presented two parallel lobes including a gap-like seed-cavity in cross section。 In addition, the mature seeds inpidually with an embryo could mostly germinate, and in which very few seeds were rotten。 The fleshy testa obviously inhibited the embryo germination。 The later-ripening of the embryo was not evident。 Besides, the condition of the seed overwintering outdoors could decrease the inhibition of the germination。 

This paper is with 23 figures, 2 tables, 20 references。

Key Words: Ginkgo biloba L。  germination  ovules  outer seed coat  development  Anatomy  reproductive organs  seeds             

摘要 Ⅰ

ABSTRACT Ⅱ

图清单 Ⅳ

表清单 Ⅳ

1 绪论 1

1。1银杏胚珠-种子发育和种子萌发特征 1

1。2栽培技术 2

2 材料和方法 3

2。1实验材料 3

2。2实验方法 4

3 结果和分析 5

4 讨论 10

4。1胚珠-种子形态结构和发育 (责任编辑：qin)