【作者】 俞晓曲；

【导师】 郑诚乐；

【作者基本信息】 福建农林大学 ， 果树学， 2006， 硕士

【摘要】 锥栗（Castanea henryi Rehd. & Wils）是我省特色果树资源，具有很高的食用及药用价值。但由于锥栗长期采用实生繁殖，遗传背景复杂，生产上常出现同物异名和同名异物现象，造成品种类型的分类混乱；同时锥栗生产上也普遍存在空棚现象，造成产量下降和品质降低。本研究以锥栗果实、嫩芽及花粉为材料，探索锥栗胚胎发生发育过程及其种质资源的遗传多样性，为锥栗种质资源的合理利用和克服空棚问题提供依据。主要研究结果如下： 1．初步探明锥栗胚胎发生发育的过程。以锥栗品种“黄榛”为材料，采用常规石蜡切片法，并制成永久切片，对胚胎发生发育进行了研究。结果表明：锥栗胚胎发育始于珠心组织中的一枚孢原细胞。孢原细胞分裂出外侧的周缘细胞和内部的造孢细胞。造孢细胞起大孢子母细胞的作用，分裂成四个大孢子，其中一个发育为功能大孢子。锥栗胚胎为蓼型，功能大孢子发育成熟时共具有七个细胞八个细胞核，通过双受精作用，产生胚和胚乳，胚胎发育经历球形胚、心形胚、鱼雷形胚到子叶胚的过程。 2．通过花粉电镜扫描，发现锥栗具有丰富的遗传多样性。以福建省锥栗主产区建瓯市采集的17个锥栗品种的花粉为材料，经前处理后进行电镜扫描。结果表明：锥栗花粉为小花粉，长球形，极面观三裂圆形，赤道面观有长椭圆形、宽椭圆形和菱形三种，萌发孔类型为N₃P₄C₅。锥栗不同品种花粉间存在差异，主要表现在花粉的纹饰上，有的花粉纹饰呈脑纹状褶皱，有的形成条纹沟，有的形成孔穴，表明其具有丰富的遗传多样性。通过花粉表面纹饰，可将这17个品种归为5类：具圆形突起、仅具孔穴、仅具条纹、具条纹与孔穴和具褶皱。此外，锥栗花粉纹饰演化是由光滑→孔穴→褶皱一条纹的趋势，可以借此来推测锥栗花粉进化先后顺序。 3．建立了锥栗基因组DNA的提取和纯化方法。为解决锥栗组织器官内多酚、多糖、色素等物质的干扰，本试验以29个锥栗品种的春季嫩芽为材料，采用改进的高盐低pH值法提取锥栗基因组DNA。结果表明：该方法能有效地去除锥栗嫩芽中多酚等杂质，所提取的DNA纯度高，完整性好，DNA得率大于128μg／g·FW，符合PCR反应要求。更多还原

【Abstract】 Castanopsis chinensis（Castanea henryi Rehd. & Wils.） has very high edible and the medicinal value, which is a characteristic fruit tree resource in Fujian. Because of long-term grown directly from seed reproduction, its heredity background is complex and varieties are confused. In addition, there is seedless phenomenon in produces, which makes the output drop and the quality reduces. This research took the fruits, the shoots, the pollens as the materials, explored the embryonic development and the genetic diversity of Castanopsis chinensis , to provide the basis for overcoming the seedless question and the reasonable use in resources. The results were as follows:1. Verifies the embryonic development of Castanopsis chinensis initiallyThe embryogenesis of Castanopsis chinensis was mainly studied on the variety of ’huang zhen’ .Materials were dehydrated, embedded and cut in Paraffin wax. The result were as follows: The embryonic development began in the nucellus tissue from a archesporium cell which would divide to a sporogenous cell and a parietal cell. The sporogenous cell functioned as the megaspore mother cell. The tetrad of megaspores was linear shaped, with one of them being functional. The development of the embryo sac belongs to the ’polygonum’ type. The female gametophyte consists of egg apparatus, central cell and three antipodal cell at the mature embryo sac stage. Embryonic development experienced golbular embryo, heart-shape embryo, torpedo-shape embryo to cotyledonary embryo.2. The genetic diversity of Castanopsis chinensis analisis by scanning electron microscope17 Castanopsis chinensis pollen varieties were gathered from main production area-Jianou as the materials. The results were as follows: the pollens belonged to small pollen type, prolate, circular AMB with 3 laesurae, three types equator- Oblong, wide ellipse, diamond , nomotreme belonged to N₃P₄C₅. The pollen characteristics of these varieties differred in the sizes, shapes, especially in the exine ornamentations, so they could provide scientific bases for variety and identification of Castanopsis chinensis. According to the exine ornamentations, these 17 varieties were classified to 5 types-circular process, hole, striate, hole - striate, wrinkle. Moreover, the smooth→hole → wrinkle → striate tendency of the exine ornamentations development would borrow this to extrapolate the Castanopsis chinensis更多还原