The Study On Characteristics Of Flower Bud Differentiation And Embryonic Development Of Adonis Amurensis Regel Et Radde

The paper mainly studied the Adonis amurensis Regel et Radde which grow in the nursery of School of Landscape Architecture, we studied the flower bud differentiation and development, flowering phenology, and embryo development, then we discussed the corresponding relationship among the growth and development process, the reproductive biological characteristics and the phenology. The resoults are as follows:The process of Adonis amurensis flower buds morphological differentiation can be divided into six stages:undifferentiation period, differentiation period, calyx differentiation period, petal differentiation period, stamen differentiation period and pistil differentiation period. Flower bud differentiation began in late June, and the whole process took approximately 40 days, and then the floral organ development was began. The anthers is 4-microsporangiate, and it is consist of five layers:the e-pidermis, the endothecium, two middle layers, and the secretory tapetum. The development of anther wall was dicotyledonous type and tapetum was glandular type. Cytokinesis is of the simultaneous type and microspore tetrads are mainly tetrahedral. Pollen grains are mostly 2-celled when shed, occasionally 3-celled type. The ovary which has single carpel and single chamber contain amphitropous ovule which was bitegmic and crassinucellate. Megasporocyte produced by sporogenous cell, after three times mitosis, it would develop into 8 cell 8 nuclear embryosac. Two polar nucleus were unfused before fertilization.The budding stage of Adonis amurensis in introduction area was in early of mid-March, and after 8～10 days, it would bloom. The flowering span of population was from mid-March to late April in Harbin. Florescence of groups was about 33-34 days, and individual florescence was 24～26 days. Comparied with 2015, the first-flowering date and final-flowering date of 2014 was one week in advance, population flowering process showed a curve of tape "M". There was a longer overlapping time of populations of flowering. The average flowering inde two years was 0.819 and 0.866. Relative flowering intensity of individual was low, which distribution frequency was concentrated between 10%～40%.The stigma of Adonis amurensis was wet type. About 2-4 hours after pollination, the pollen germination. About 20 hours after pollination, primary endosperm nucleus formed and began to split. After 7 days of pollination, male nucleolus and female nucleolus fused to form a zygote. Double fertilization type belong to premitotic type of gamete fusion. The embryogeny was of the onagrad type, and the endosperm was of the nuclear type. The dormant period of zygote was approximate 8-9 days, then split to form two cell proembryo. When the seed was mature, the embryo had not yet fully differentiated, and it was still in the early stage of globular embryo or in the early stage of heart embryo. The whole embryo development needed about 50～60 days. There was obvious morphophysiological dormancy of the seeds. At this stage, by ripening, the differentiation and growth of the embryo was completed, and the embryo grew into cotyledon type.