| Chinese fir is the most important timber tree in south part of China, and the research of flowering characteristics and its breeding is one of the most active research area. We have carried out a series of research into Chinese fir flowering characteristics in 1.5 generation Chongyang seed orchard, 1 generation Laoshan seed orchard, lgeneration Zhangle seed orchard, Lintian forest and Jujian Forestry College provenance forest, the results show that Chinese fir Phenology can be divided into 12 phases, there is a relationship between the Chinese fir clone Phenological phase in a seed orchard and its original geographical location. Because of a long time of introduction, many Phenological phase among clones appear " going to the same". We have proposed the ratio of cb/xb as index to estimate the time of male and female flowering coincidence. Using the ratio of female to male cones, the clones can be classed into mainly female clones, female and male clones and mainly male clones. Using flowering percentages of female and male cones among different clones at different dates, clones can be divided into early, mid and late flowering clones. Based on the time of male and female flowering coincidence, clones can be grouped into early female flowering late male flowering clones, coincident male and female flowering clones and late female flowering early male flowering clones. The regression between Chinese fir female cone developing course and date is a logarithm, the regression between Chinese fir survival rate and date is negative linear, and diseases, insect pests and disaster weather are the main factors which lead cones to death. The pollen dispersal has its own release pattern and day-night cycle. Vertical pollen distribution is as a cluster one, horizontal pollen distribution in seed orchards and in normal forest is a uniform distribution type, outside seed orchards and normal forest pollen distribution is diffusible. Wind speed is the most important factor for pollen dispersal. The relationship between pollen quantity and distance to a seed orchard is linear. When a pollen leaving from its pollen sac, the pollen makes a evenly sedimentation movement and the wind, topographical factor can effect this movement as well, which make pollens ascend and mix with wind to decrease self-fertilization rate. Male cones and female cones have their own distribution regions in tree crowns, male cones are located in the middle to top and female cones the middle to bottom part of tree crown, and because of lower density for mother trees in seed orchards than that of in a stand, female cones are distributed over the whole of the mother tree crown in seedorchard. Chinese fir male cones and female cones appear to be very well adapted for wind as the pollination mechanism. There are no obvious differences for the number of pollen grains produced by one pollen sac among trees in the same clone, but there are obvious differences among clones. There are obvious differences both among clones and between years in female cone number, male cone number and their ratio. We have proposed the index of Rm and Rc as the pollination level in a seed orchard. The accumulation pollen during pollination period (Rc) should be 3-5 pollen grains / mm2 to guarantee fertilization. Chinese fir seed orchards in this study produce too much pollen, which is 4-56 times as Rc, and could be improved by increasing the number of mother trees which produce more female cones or stimulation more female flowers in these seed orchards in order to produce more seeds. Chinese fir pollen is almost like a ball with an equator axes length 39.9μm, a pole axes length 37.4μm, a volume of 30219μm3 and a weight of 1.98x10~-5mg. The pollen number produced by 1 sac of a Chinese fir tree is 2300-12000 grains, and the average pollen number per tree 7.8311x10~9, about 1.5539xl05mg, the average ovule number 39240.55. One mother tree in seed orchard can produce pollen 2.1891x1010, about 4.3438xl05mg and ovule 53199.25. On the pollen surface there are lot of Wu-body pattern, and there is a aperture on pollen surface as well, and the aperture varies very much among provenance Chinese fir. The pollen wall is composed of 2 layers, i.e. exine and inxine, the exine can be divided into sexine and nexine else. We can find Golgi-body, endoplasmic reticulum( ER), mitochondria, nucleolus and so on inside pollen. The useful way for the vigour test is to dye pollen with ink, the dyeing time for clones is from 12.65 to 30.17 minutes. Boron is very important for pollen germination, without it in the culture medium, pollen germination is restrained, with the culture medium of 1-50 ppm boron acid a pollen germinates well. Apart from the normal germination pollen tube morphology, there are abnormal morphological types. The are differences of peroxidase isozyme among Chinese fir provenance pollens. There are obvious differences for morphological characteristics both male cone and female cone, the distributions of male cone and female cone morphological characteristics are not normally distributions. There are different types for both male cone and female cone. In Chongyang seed orchard the average female cone diameter, female cone length, macrosporophyll number, macrosporophyll width, macrosporophyll length, total seed number, good seed number, empty seed number, Se-seed number and the one-thousand grain weight of clones are 26.53mm, 30mm, 52.30, 12.45mm, 14.86mm, 72.90, 17.73, 19.72, 35.33 and 9.41g respectively. The correlation coefficients are reach to significant level for the follow items: between female cone diameter and length, among each kind seed, and among macrosporophyll items. There are obvious differences for every kindseed number in a cone and female cone morphological items among clones. This information tells us that clone composition plays a very important role for seed production in a seed orchard. We can obtain three components by means of varimax with Kaiser normalization rotation factor analysis and name: macrosporophyll factor, female cone-seed factor, and seed factor. With good seed number per cone all clone female cones can be classed into 4 groups by means of Hierarchical cluster. There are obvious differences for 1000-grain weight, purity and vigour among families, and the family seeds can be divided into 3 quality groups by means of K-means with purity, 1000-grain weight, seed moisture content, vigour, Se-seed, empty seed and germinating.Based on the characteristics of Chinese fir flowering, we make some suggestions for Chinese fir seed orchard establishment or improvement: in order to decrease or perish self-fertilization rate we can do by increasing the clone number, increasing mother trees which produce more female cones or stimulating mother trees to yield more female cones. To chose clones with high female cone yield and high seed quality when we set up a new Chinese fir seed orchard. To carry a artificial pollination according to pollination regulations during the pollen dispersal season when it needs. To manage the Chinese fir seed orchard intensively to decrease abortion rate for both female cones and seeds.
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