| The reproductive biology and propagation of Viburnum macrocephalum f.keteleeri were studied. Theresults showed that:Analysis of phenology: The main vegetal phenology was divided into Budding stage, Leaf spreadingstage, Flowering stage, Fruit maturing stage and Dormancy stage. The Flowering phenology stage wasmade up of beginning of bloom, full flower period of bloom and last period of bloom.Morphological differentiation of the flower bud: Bud differentiation may be divided intopredifferentation, the initial differential phase, inflorescence primordium differential phase, the sepaldifferential period, the petal differential period , the stamen differential period, the pistil differentialperiod.Morphological anatomy of the fertile and infertile flower: A fertile flower has a dry stigma with 1 pistiland 5 stamens and a infertile flower has degenerated stamens and a pistil. The degenerated characteristicrepresent as abnormal filament, anther, stigma and ovule. The infertile flower abortions divide intostructural, nutritional and physiological type.Ultra-Structure and anatomical structure of floral organs :The mature flower is composed of calyx,petal, stamen and pistil. Style of viburnum is model of occlusion, composed of mastoid cell,parenchyma cells and transmitting tissue. Endoplasmic reticulum and golgi body vacuolizes.Pollination biology: Pollen/ovule ratio (P/O) and breeding systems belong to obligate xenogamy andinsect pollination. The main flower visitors are bees and butterflies. Pollen grains began to germinate 1hour after pollination and then pollen tubes penetrated the stigma through the papilla clearance. Theycontinue to grow along the transmitting tissue in center of style. Some pollen tubes reached the ovary18 hours later and grew into ovule through micropyle 20 hours after pollination.Configuration and anatomy seeds: There are 2 shallow channels on upside surface and 3 shallowchannels on underside surface of a seed. Seed kernel consisted mostly of endosperm. Embryo is verysmall. Seed coat structure is made up of epidermis, middle layer, palisade layer and inner film.Anatomical structure of vegetative organ: The distribution of epidermal hair on the surface of leaf issparseness as in single line and acervate state, and is serried as starlike awn underside of leaf. Thevascular bundles of leafstalk are 'D' shape. Electrophoretograms of peroxide isoenzyme suggest thephotosynthetic efficiency of leaf during different period of development having significant differences.Ultra-Structure of developing chloroplast: Mature chloroplast multiplicate through budding whileprimary chloroplasts become chloroplast The shape of chloroplasts in leaf present solely on spheroidaland spheroidicity after mature. Grana lamella rank dense and stroma lamella relax, with large quantityof osmiothilic material. Chloroplasts in old leaves have small bulk and quantity, irregular form ispredominate. All the structure of basal granule thylakoid have disaggregated, the number of granalamellae have decreased.Karyorype analysis: The number of chromosome is 2n=18 and karyotype formula is2n=2X=18=10m+5sm+3st, and As.K%=64.3. The karyotype is belonging to "2B" type.Development and principal components of fruit: The growth patterns of fresh and dry weight ofV .macrocephalum fruit showed double"S"curves. The content of Vc in ripe fruit was very high..The factors influencing seed dormancy: Seed dormancy may not be caused by seed non-soakage. There are inhibiting substances in seed kernel, especially in seed embryo. 4℃ for 60 days Cold storage before 25 ℃ for 90 days warm storage can break seed dormancy and then seeds germinated at 15℃. Mature seed embryos germinate at October in the next year when dormancy was broken. Germination of seeds:the germination rate of dry seed is high when sow early. Seeds cannot germinate when sow late for June and it only germinate at autumn. Storage in sand at room temperature, sowing shallow and vermiculite can get maximal germination rate of seeds.
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