| The thesis studied mainly these contents on Phoebe chekiangensis Shang: The mechanism of dormancy and germination condition; annul growth rhythm of one-year seedlings and reserved seedlings; adaptability to light and soil moisture status in seedling stage; breeding techniques of seedlings; ability to resist cold.1.The seed coat of Phoebe chekiangensis Shang is hard, it is inferior in air permeability, on the other hand, it is superior in water permeability. After sacrificing seed coat, seeds were mostly decomposed, so the seed-coat obstacle is not the main cause of the seed dormancy, sacrificing seed coat treatment is not suitable for overcome the seed dormancy. We deduced that the seed dormancy of Phoebe chekiangensis Shang was caused by physiological factors, because both cold stratification and temperature -accelerated stratification treatments can overcome the seed dormancy. The treatment of GA is not also proper, because it will accelerate seeds to degenerate, percentage germination and germination capacity will decrease in some degree.2. Cotyledons of Phoebe chekiangensis Shang emerged when seeds germinating. One seed has more embryos, and it can germinate 1-3 seedlings, or 4 seedlings. The percentage germination of seeds was 60-78%. The growth patterns of height and diameter are fitted for S curve and can be simulated with Logister equation. At the same time, the growth period of both height and diameter is divided into 4 stages according to its growth rate: emergence phase of seedlings growth, initiation phase of seedlings growth, prosperous phase of seedlings growth, and later phase of seedlings growth. In one year, there are Stimes growth peaks. The growing of reserved seedlings present ladder-form in one year, belong to spring and summer growth type. Fast growth phase get through 180 days from the first growth peak to the last growth peak. In this phase, seedlings sprouted for 4times, so there are 4tim.es growth peaks. Taproot of Phoebe chekiangensis Shang is stronger, so the underground growth of one-year seedlings is more than the aboveground growth.3.The emergence rate of seedlings is different too, if sowing density is different, the biggest is 88.8%, the smallest is 63.2%, and average is 78.6%. The change is irregular, so there are not direct relation between the emergence rate of seedlings and sowing density. Along with the sowing density increasing, height growth almost not change, but root diameter growth falls. To ensure the seedlings quality and quantity, the best sowing density is 16-200grains/m2.4.On condition of sun shading, change of the individual leaf area is slight, but change of individual dried leaf weight is evident. In the full light, individual dried leaf is the heaviest, this indicate that the dried material accumulated is the most. On the other hand, on condition of sun shading, leaf area per dried leaf weight increases, but dried weight per leaf area and photosynthesis ability decrease. Light affects theoutside forms of seedlings: branching number and leaf number get small, while crown diameter of individual tree narrows, assimilation area grow few. In addition, content of chlorophyll a, chlorophyll b and chlorophyll a+b will increase on condition of sun shading. The net photosynthetic rate is higher on condition of full light and slight sun shading, seedlings growing is vigorous, the accumulation of CH2O is more, so dried leaf weight, branch biomass, root system biomass and total biomass per seedling all is more. On condition of heavy sun shading, the net photosynthetic rate of seedlings is low, the accumulation of GH2O is few, and seedlings grow slowly.5.The regulate ability of Phoebe chekiangensis Shang to soil water is strong, slight drought and flood will not bring evident influence to its growth.6. In Nanjing, the one-year seedlings of Phoebe chekiangensis Shang will suffer certain winter killing in winter, but this will not affect seedlings growing in next year, and net growth will reach 60-90cm. In general, two-year and above two-year seedlings...
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