| This paper studies pollen viability, pollination capability and embryogenesis of Irismandshurica by means of indoor experiment, outdoor observing and paraffin wax. The mainresult are as follows:(1) The pollen viability become gradually fragile with the time prolonging;The pollen which indarkness and stores in refrigerator that the temperature as low as 4 degree Centigrade,still could maintain more than 30 percent viability with in 24 hours. The flowering of Irismandshurica is largely influenced by climatic factors.(2) Iris mandshurica could bear fruits artificially in own flowers and the rate of bearing fruit ishigher; the effects of cross-pollination were well; the best time for pollination was 8:30 inthe morning; the rate of bearing fruit by natural pollination is also higher; the floweringperiod is 20 days, single flower lasts 8 hours.(3) Cytokinesis in the microsporocyte meiosis was of the continuous type. Microspore tetradswere tetrahedral.Mature pollen grains were 2-celled.(4) The ovary was three locular; axial placenta. Ovules were anatropous, bitegminous andcrassinucellate. The meiosis of megaspore mother cell are normally. The megaspore tetrad islinear, but only the megaspore near the chalazal end remain.The formation of embryo sac isPolygonum type.(5) The mature period of male gametophyte are earlier than female gametophyte.(6) After artificial pollination 24 hours, pollen tube get into one of synergids and occursfertilization phenomenon. Double fertilization is the type of the premitotic gametogamy.(7) The duration of zygote dormancy was about three days. After 4-6 hours,the primaryendosperm nucleus begins dividing and then forms 2 endosperm cells, and the developmentof endosperm is nuclear type.
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