Introduction Of Eucalyptus In Hefei Region And The Study Of Cold Resistant To Winter Hardness

Because of its fast - growing and high - yield, strong adaptability, wide use, and short rotation and economic value of high, Eucalyptus became the second of the afforestation species in the world. The introduction, cold resistance and selection of Eucalyptus is very important. There is still a great potential about introduction of Eucalyptus in China. Hefei is a great transitional belt because of ample rainfall, heat and light conditions. It is also a great transition zone for the introduction and acclimatization. If the not cold - resistant plants planted in Hefei, it will broaden ecological potential and create favorable conditions for gene mutations, thereby it will lay a foundation for variety breeding under the adverse circumstances.In this dissertation, four Eucalypus were used as experimental material, select the best choice. The introduction and domestication experiment of four kinds of Eucalyptus were carried out in Hefei area in 2004, and the botanical characteristics, cold resistance, and introduction survival rate were investigated in 2005 and 2008, and primarily selected as superior provenance that suitable for cultivation in Hefei. Then cutting the Eucalyptus varieties which were selected to expand the quantities of varieties. In the end, to explore the physiological and biochemical mechanism of Eucalyptus during low temperature stress, the changes in contents of electrical conductivity, soluble sugar contents, Pro, chlorophyll fluorescence characters. The major results were summarized as follows:1. Four Eucalyptus were used as experimental material, select the E. rubida for the best choice.2. Select the appropriate hormone treatment method through orthogonal experiments, concentration and time. It is concluded that the best procedure is 500PPm NAA+300PPm IBA+0.4% sugar.3. The electrical conductivity of E. rubida is the lowest through the determination. LT50 of E. rubida, DH-32, U-6 and the No.9 is -16.32℃,-14.25℃,-12.28℃and -11.56℃.4. Soluble sugar contents and Pro can be used as instructions of plant cold resistance of key indicators.5. Chlorophyll fluorescence characters can be used as an ideal means of study on low temperature stress because it is very sensitive under cold conditions.