| Raspberry, small fruit of Rosaceae, Rubus L., has two types according to the time of fruit forming: summer bearing and primocane bearing. Both 2-years and 1-year cane of primocane bearing type can produce fruits and we can use 1-year cane, which need not be buried in winter to reduce the cost. Now, there are some reports about the flower bud differentiation of summer-fruit type Raspberry in China and there is still a blank in the study of Raspberry procreate biology. In this paper, we took summer-fruit type'Orus'and autumn -fruit type'Summit'as experimental materials, with paraffin cut section method, we observed the developing process of flower bud differentiation, development of microspore and megaspore, development of male and female gametophytes, and anatomical structure of fruit. The changes of stored pollen energy under room and low temperature were tested with TTC. Pollen morphology was observed with scanning electron microscope (SEM). Effects of stigma receptivity, effective pollination period, pollination ways on setting fruit rate and seed germination ability under different treatment were studied. The main conclusions as follows:1. The flower bud differentiation process of Raspberry included pre-differentiation stage, early differentiation and small flower differentiation stage. The small flower differentiation stage included stage of sepal primordium differentiation, stage of stamen primordium differentiation, stage of pistil primordium differentiation made of a lot of apocarpous pistil, and stage of petal primordium differentiation. In Harbin, There was no much difference in the process of flower bud differentiation between 2-years and 1-year cane of'Summit'and 2-years cane of'Orus', except the period of flower bud differentiation.2. The characteristics of micro -megaspore and male -famale gametophytes: the anther wall was dicotyledonous type and the tapetum was secretory. There were many microspore mother cells, the meiosis tetrads were tetrahedral, microspore was circle and smaller, and the male gametophytes were 2-cell types.The embryo sac was polygonum type , there were two ovules in each ovary, one was degenerate, the other was developped normally, the ovule was anatropous.3. The mature pollen was circle with three germinal furrows. The exterior wall of pollen was a reticulation. There was a lid on the germination aperture ,and there were small grains on the surface layer of germination furrows with cover.4. The pollen vitality was up to 50% in'Summit'whereas decreased to 38.26% and 44.59% in'Orus'afer the pollens were stored under room temperature and low temperature in the refrigerator for 20 days with TTC method.5. The stigma receptivity of'Orus'could last 24 hours, and stigma receptivity of'Summit'could last 30 hours. The effective pollination period of'Orus'was 7 days, and that of'Summit'was 4 days. The self-fruitful percent,natural-fruitful percent and artificial pollination percent of'Orus'were 52.73%, 84.73% and 72.46% respectively, and that of'Summit'were 46.33%,90.62%,79.61% respectively.6. Fruit of Raspberry was composed of pericarp and seed. The pericarp had 3 layers from outside to inside. Exocarp was thin and velvet. Mesocarp was composed of multi-layer parenchyma cell .Endocarp composed of a lot of fibrous scleroid cell . Fruit type was aggregate stone fruit. There was only one seed that has seed coat and embryo. The seed coat was thick and arranged tightly with multi-layer cell.7. The fruit growth curve of Raspberry was"double S"curve. There was one slow development period between the two fast development periods, but it lasted shortly.
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