Study On Pollination Ecology Of Pyrola Dahurica (H.Andr.)Kom.

Recently Pollination Ecology had became a popular field in Population Biology and Evolutionary Biology, researching of biological characters and its laws in relation to pollination. Study on Pollination Biology is the core subject of Plant Sexual Reproduction. That Pollination system consisted of three parts including pollen, stigma and pollination medium that is the most important factor attributed to the diversity of Angiosperm. Since pollination is the necessary stage of fertilization among Spermatophyte, the movement of pollen restricted the individual gene floating and mating modes between colonies. Consequently, the movement of pollen affected hereditary combination and Adaptation.The rules of Reproduction and pollination ecology of Pyrola dahurica(H. Andr.) was mainly expatiated from shape dissection, pollination, Embryonic Development, colony pattern and other aspects in this thesis. The experiment of Shape anatomy was employed by the method of traditional paraffine-slicing while studying on pollination biology reckoned on fieldwork, paraffine-slicing, electron microscope scanning and other ways.At the same time embryology is mainly dependent on paraffine-slicing while Population pattern is researched through field investigation, quadrat method, nearest-neighbor method, evenness method and others. Being revealed structure of Vegetative and propagative organs by Anatomical method is for getting further to explain relationship between them and pollination ecology. It was made out that P. dahurica, rules of reproduction system, pollination insects and their pollination behaviour, blossom dynamic, stigma dynamic, co-evolution, herkogamy of Visiting frequency and pollen flow through the research of pollination biology of P. dahurica. Infertility mechnism and developmental characteristics of female and male gametophytes was illuminated through the research of Embryology of P. dahurica. And the law of spatial distribution patterns of P. dahurica was accquired following the population pattern researched. Trying on applying the evenness theory to measurement of the population pattern, we indicated the relationship between population pattern and the population fecundity. The Specific research results as followed:The stem of Pyrola dahurica(H. Andr.) Kom was rhizome, the stem was provided with the primary structure and secondary structure, vascular bundle was scattered in the primary structure, the Xylem had 2～3 annual ring. leaves was equilateral, no differentiation of sponge tissue and palisade tissue, had the characteristics of growing in drought area of developed corneum and mechanical tissue, upheavaling vein. It could be concluded that P. dahurica was a sort of Carbon-4 plant from anatomical structure of its leaf vein; Its pollen was combined, style with structural gland was the type of dissociation, The Condia was tetrahedron shape, each pollen cultured in the medium would germinate a pollen tube, while pollen in the stigma would grow into 1～2 germ tubes and where it germinated was uncertain. Seeds took on spindle shape, its testa was Separated and transparent, its embryo was ateliosis, endosperm besieged embryo, style was round, stylar canal was pentagon, advanced spermaphore was axile placenta.Pyrola dahurica(H. Andr.) Kom was self-sterile and apomixis traits. The seed setting percentage was very low(only10％), P. dahurica adopt cross-pollination as reproductive countermeasure, which pollination insects mainly included phaonia hybrida(Schnabl)lapping the secretion of its stigma, Piidonia puziloi(Soisky) ingesting its pollen, phaonia hybrida (Schnabl), and a few species of honeybee family, such as Bombus, eating its pollen.Co-evolution relation came into being in long-term evolution and natural selection among P. puziloi,phaonia hybrida(Schnabl) and P. dahurica. It was at noon that the peak of visiting frequence within one day of P. puziloi occurred, the peak of visiting frequence of phaonia hybrida(Schnabl) and a few species of honeybee family occurred twice one day. The time period of visiting flower was different owing to effect of the temperature of environment, a few species of honeybee family prefered to visiting at higher temperature when the flower was about to wither.P. puziloi favours warm and cool weather, therefore, Its visiting time was concluded before flowering. The active peak of phaonia hybrida(Schnabl) was just the flowering bloom period of P. dahurica. visiting route of P. puziloi took on "zigzag shape" and "broken line form", and its distance of calling on flower was shorter than that of phaonia hybrida(Schnabl). The pollen flow of P. puziloi and phaonia hybrida(Sehnabl) were completely different, the former pollen flow direction was mainly radial which the most of pollen was accquired due to its near distance from the marker plant, and the latter one was dispersing which the few of pollen was accquired due to its far distance from the marker plant. The accomplished pollen flow direction by the latter was more dispersing than the marked one in the sample area.Movement herkogamy was one of characteristics of Pyrola dahurica(H. Andr.) Kom including the change of their position on style and stamen and dynamic change of style by itself. The former consist of 6 stages in order to avoid the interference between male and female; the latter included 5 phase in order to enhance style's acception to the pollen.Embryology characteristics of Pyrola dahurica(H. Andr.) Kom was anatropous, thin nucellus, biteginous, building cell directly developed into megaspore mother cell, The development of embryo sac belongs to polygonum type with majority of ephemeral antipodal cells, During the period of Spore, embryo sac and embryo formation abortion occurred in various degree, which total percentage was 90％. Abortion was mainly because of the division asynchrony of most of megaspore mother cell, Developmental abnormality of female gametophyte and spermatization failure, otherwise, the abortion was mainly caused of agenesis of endosperm in the late stage of embryo. Environment was important impact factor on the development of female gametophyte. Seeds embryo only develops partially in the process of seed formation, seed was in possess of a very long wing originated from testa.The developmental characteristics of the anther sac was the thickened Epidermis of anther chamber instead of the chamber inner-wall's protection. The 2-3 layer interlayer disappeared when the pollen matured. The tapetum originated from cytoclastic tapetum cell when the disformed microspore of tapetum type makes meiosis. The development of microspore mother cell was asynchronous in the same chamber. Spore mother cell in the peripheral part degenerated and die away, male gametophytes developed into 2-cell. The embryonic development of P. dahurica did not all belong to the ephemeral plant of short growing period which abortion mainly depended on climatic factor.Distribution patterns of population of P. dahurica was measured respectively by quadrat method, nearest-neighbor method and evenness method in small scale measurement, the measurement result indicated that distribution patterns of population of P. dahurica belonged to random distribution by the three method, among which the evenness method was first applied to the measurement of spatial distribution patterns of population, it was accurater to measure the type of spatial pattern than quadrat method and nearest-neighbor method because of its neither size restriction of populations nor quadrat and being irrelative with population density with more excellent results in comparision with two others, it was more of practicability than Point pattern analysis in practice because of its no complicated computational process. It was indicated that index of patchiness of P. dahurica population was inverse ratio to transmittance and PH value of soil, proportional to total porosity of the soils and bulk density of soil. Therefore, It was found out that the spatial pattern of population was closely related to flowering percentage and breeding ecology.Pollination ecology has been paid more and more attention to, the research result of Pollination ecology was of importance for discovering the propagation law of plant. Pollination ecology of P. dahurica was regarded as the studying core and the reproductive biology of P. dahurica was elaborated at a different angles in this article. Because this was the first article reported about the sterility law of P. dahurica, The research results was expected to lay the foundations for further studying on Breeding Ecology of P. dahurica.