Overwintering Ability Of Four Kinds Of Off-season Transplanting Trees

In this thesis, Ulmus densa Litw., Fraxinus rhynchophylla Hance., U.lapvis Litw., and Populussimonii Carr. planted in China-Eurasia Expo were uesd, and local varieties were taken as controls. Undernatural overwintering in2011and2012, physiological indexes of the four kinds of off-season transplantingtrees were measured and the cold resistance was studied. The major results are as followed.1. During nature overwintering in2011, the electrolyte leakage rate, the contents of MDA, solublesugar, soluble protein and bound water/free water of transplanting and control groups both rose at first andthen declined.While the contents of moisture water declined at first and then rose. And the contents ofstarch content declined. The electrolyte leakage rate and MDA content of transplanted trees weresignificantly higher on than the control groups in2011, which indicated that the degree of impairment oftransplanted trees’ membranous was severer than the control groups. The contents of soluble sugar andsoluble protein in transplanted trees of Ulmus densa Litw., U.lapvis Litw., and Populus simonii Carr. weresignificantly higher than the control groups, and maintained a high level in Fraxinus rhynchophylla Hance.The contents of starch were significantly lower in transplanted trees than the control groups. There was nosignificant difference in contents of moisture water and the peak ratio of bound water/free water betweentransplanting trees and control groups. In conclusion, during nature overwintering in2011, transplantingtrees had suffered a certain degree of membranous injury, and also had produced more protectivesubstances than the control groups, the bound water contents had increased, improved the resistance ofplants to low temperature,which made them live through the winter properly.2. During nature overwintering in2012, the highest contents of electrolyte leakage rate and MDA of4kinds transplanting trees were significantly decreased compared to2011. The contents of soluble sugar andsoluble protein of transplanting Ulmus densa Litw., U.lapvis Litw., and Populus simonii Carr. significantlydecreased in2012compared to2011. The contents of soluble sugar of transplanting Fraxinusrhynchophylla Hance. significantly increased compared to2011, but there was no significant difference inthe peak contents of soluble protein between2011and2012. The contents of starch of transplanting treessignificantly increased in2012compared to2011, but there was no significant difference in the peak ratioof bound water/free water of transplanted trees between2011and2012. In conclusion, the ability to adaptto low temperature returned to normal.3. By comparing the subjection analysis on cold resistance indicators of the four off-seasontransplanting tree species, the cold resistance abilities of4kinds transplanting trees can be ranked as:Populus simonii Carr.＞Fraxinus rhynchophylla Hance.＞Ulmus densa Litw.＞U.lapvis Litw. The coldresistance abilities of4kinds control group trees can be ranked as: Populus simonii Carr.＞Fraxinusrhynchophylla Hance.＞U.lapvis Litw.＞Ulmus densa Litw. The transplanting Populus simonii Carr. hasthe strongest cold resistance abilities, the cold resistance abilitiy of tansplanting Ulmus densa Litw. isstronger than U.lapvis Litw.due to the impact of cross-adaptation.