A Study On The Biology Of Osmanthus Fragrans Lour.

This dissertation studies the biology of Osmanthus fragrans totally and systematically. Through outside observation, barehanded chipping, wax section and etc., the vegetative organs(root, stem and leaf) of Osmanthus fragrans and its reproductive organs(flower, fruit and seed) were investigated carefully by the technology of optical microscope and electronic microscope. The karyotype of Osmanthus fragrans was studied by slide-crushing. The affined relationships of the cultivars of Osmanthus fragrans in Henan province were analyzed with molecular biological method. The especial culture of Osmanthus fragrans in China was summarized primarily. There are a few of conclusions as follows:1. The primary structure of Osmanthus fragrans root consists of epidermis, cortex and vascular cylinder. The long axes of epidermis cells are vertical to the circumference of root. Exodermis and endodermis exist obviously. The root is named as pentarch. The secondary growth of root is huge. There is a little of phloem fibre in secondary root phloem. The primary structure of stem consists of epidermis, cortex and vascular cylinder too. There are a few of glandular hairs on its epidermis. Vascular bundle is of collateral bundle. There is much phloem fibre in secondary stem phloem. These phloem fibre exists in a shape of ring. The leaves of Osmanthus fragrans are composed of epidermis, mesophyll and veins. There are extrafloral nectarines on leaf's epidermis, named as nonstructural nectary. The mesophyll has a few of cell layers. They can be classified palisade and spongy tissue. Many stone cells scatter in them.2. The inflorescences of Osmanthus fragrans are dichasium or pleiochasium. Through author's observations and anatomic studies, the secretory structures of Osmanthus fragrans are defined in its corolla totally. A whole corolla of a flower is a secretory origin secreting scent substances, named as osmophores. The anatomic structure of petal is composed of epidermis, elementary tissue and vascular bundle. There are plenty of epidermis hairs on the petal's epidermis. They appear in the shape of brush, named as brush-shaped hair. Its elementary tissue is parenchyma, playing some roles on the secretory materals of synthesis and temporary storage. The structures of vascular bundles are simple, consisting of primary xylem and primary phloem. The functions of these vascular bundles are considered as the transportation of vegetative substances and water.3. The meiosis of microspore mother cell of Osmanthus fragrans 'Ziyingui' is of simultaneous type. Its tapetum is called as secretory tapetum. The microspores show a tetrahedral arrangement. The mature pollen grain, i. e. male gametophyte, is of 2-celltype. Its tenuinucellate ovule has single integument. Hypostase and special integument tapetum exist in the ovule. The development of its sac is of Polygonum type, and embryo development is of Onagrad type. The development of endosperm is of cellular type. The mature seeds have rich endosperm.4. The number of the somatic chromosome of Osmanthus fragrans is 2n=46. The basic number of chromosome is x=23. The index of relation length is 6L+12M2+24Mi+4S. The karyotype formula is summarized as 2n=2x=46=30m+6sm+8st+2t. The karyotype belongs to 2B type of Stebbins' karyotypic symmetry. The index of karyotype asymmetry(As. K%) is 64.09%.5. An improved CTAB method was used to extract DNA from leaves of Osmanthus fragrans. RAPD was used in the classification and identification of 17 Osmanthus fragrans cultivars in Henan province. Fifteen better 10-bp primers selected from one hundred arbitrary primers was applied to amplify. Total 121 bands were produced, in which 87 bands were polymorphic. Genetic distance between each of the cultivars was calculated from simple matching coefficies. A dendrogram showing genetic relationships between them was constructed by an unweighted pair-group method with arithmetical averages(UPGMA). The genetic relationships among different cultivars groups were farthe...