| Ilex (mostly evergreen) is a genous of dominant tree species in evergreen broad-leaved forest of Zhejiang province. Ilex is ornamental and greening tree, also has the medicinal value. And it has the potentialality to be exploited and hasn't been widely used in landscaping yet.In this thesis, 4 species of native Ilex of Zhejiang provience (Ilex pubescens, I. virdis, I. cornuta, I. zhejiangensis) serving as the experimenta materials, observe their biological characteristic, view and admire the properties in detail, and study effect of stratification on the germination rate. Furthermore, 3 species (I. virdis, I. cornuta, I. zhejiangensis) serving as the experimenta materials, analyse the effect of out-come hormone on the cutting propagation and take measure of photosynthetic characteristics.The main results are described as follows:1. According to the systematic investigation of 4 different distribution in Zhejiang province, 4 species of Ilex with great shade tolerance capability, can survive under ever green broadleaf forest with density canopy. The study show that not all the seeds of Ilex trees should be germinate in the third year after collecting, I. pubensens and I. viridis germinate the next year both keep seed in natural condition and after storing seed in sand under low temperature. Storing seed in sand under low temperature can vernalize the germination rate. The germination rate of I. pubensens and I. viridis is 28.8% and 26.7% after storing seed in sand for 2 months, respectively higher 6.3% and 5.9% than storing seed in natural conditon. The germination rate of I. cornuta and I. zhejiangensis is 19.8% and 2.6% after storing seed in sand 14 months, respectively higher 5.8% and 6.1% than storing seed in natural condition. But in all, the germination rate of 4 kinds of seeds are low, and it maybe connect with the mechanical restraint of the seeds coat and the air permeability, the real cause is needed to further research.2. 3 Different kinds of hormone (NAA,IAA,IBA)and different concentration both have effect on the rooting of the cuttings, suach as the number of the adbentitious rooting and the length of the longest adventitious rooting. When the concentration of NAA is 100 mg/L, the rooting rate of of the cuutiings of I. viridis can reach 32.66%, higher 20.15% than contrast. While the concentration of IAA is 300 mg/L , the rooting of the cuutiings of I. cornuta and I. zhejiangensis can reach 75.39% and 51.72%, respectively higher 14.52% and 10.42% than contrast. The study also show that the low concentration of hormone has plus effect on the rooting of the cutting, while too high density could inhibite the rooting traits.3. The gas exchange and chlorophyll fluorescence parameters in leaves of different tree species under field conditions. The results showed that light compensation point is 20.94μmol·m-2·s-1 in I. virdis , 29.91μmol·m-2·s-1 in I. zhejiangensis,24.02 in I. cornuta ,it showed that had no significant difference in three species ; Light saturation point had significant difference in three species , Light saturation point in I. cornuta is much higher (1516.67μmol·m-2·s-1) than other two species (respectively 1204.29,1305.10μmol·m-2·s-1); Maximum net photosynthetic rate is different too, Maximum net photosynthetic rate in I. cornuta is higher (8.43μmol·m-2·s-1 ) than other two species (respectively 3.33,5.53μmol·m-2·s-1), indicating that I. cornuta had higher photosynthetic capacity and stronger utilization ability for light energy. The electron transport rate(ETR), PSⅡefficiency(Yield) and photochemical quenching (qP) in the leaf were much higher in I. cornuta than in I. zhejiangensis,I. virdis. Knowing photosynthetic characteristics of Ilex is good to exert ecological benefit in plant community and provide theoretic guidance for planting design.4. According to biological and ecological characteristics, Ilex can be used as evergreen ground cover plants, afforesation seeds, hedgerow, etc. Furthermore, the paper take the example of the introduction of 17 species of Ilex in Zhejiang forest College Eastlake Campus, the suggestions such as introducing 7 species of Ilex(including 3 species the paper researched but hasn't been exploited yet)and expeditions of introducing Ilex are discussed.
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