Study On The Regional Introduction Experiment And Adaptability Of Canadian Sugar Maple

Canadian sugar maple is widely distributed in North America with strong adaptability,high ornamental value and rich colors.It is one of the world’s three largest sugar woody plants with a high commercial value and broad application prospect in the word.According to the comparision of the growth of sugar maple introduced to different places in Anhui province,combined with the physiological analysis of high temperature stress,we attempt to select appropriate provenance of sugar maple and places that are suitable for introduction.Seed from three Canadian provenances including Ontario,Quebec and Manitoba were introduced to Jixi,Shucheng,Hefei and Fuyang in Anhui,China for study of regional introduction and adaptability.Based on the analysis of germination rate,preserving rate,seeding height,ground diameter growth and other indicators of sugar maple from different provenances in different areas;artificial simulation of high temperature thermal resistance;measurement of photosynthesis under high temperature conditions in summer,we got the following conclusions:（1）Based on the measurement and record of seeding survival rate,seedling length and the growth of ground diameter value of sugar maple from 3 different provenances（Ontario,Quebec and Manitoba Provinces）.The results were as follows: Preserving rates of sugar maples among different provenances are differed significantly Preserving rates of sugar maples from Toronto and Quebec is obviously larger than Winnipeg.The height and diameter growth of sugar maple from different provenances in the same experiment are different,in general,sugar maple from Toronto has the largest growth,then Quebec,followed by Winnipeg.Germination rate,seedling length and the diameter growth of sugar maple from Toronto provenance is higher than other 2 provenances,which indicates that adaptability of sugar maple from Toronto provenance is better than other 2 provenances of sugar maple and Toronto provenance is the first choice of introduction.（2）A comprehensive comparison of the germination rate,preservation rate and growth index of sugar maple planted at 4 different areas in Anhui（Jixi,Shucheng,Hefei and Fuyang）indicated that: the germination rate of sugar maple for testing from Toronto and Quebec city provenances in Shucheng test area is more than 60% and reservation rate is as high as 90%.And the germination rate and reservation rate of sugar maple from Winnipeg provenances is 50.03% and 69.13%,respectively.The germination rate and the preservation rate of sugar maple in Shucheng plot are better than the other 3 plots.The annual growth of sugar maple from different provenances in Shucheng plot were as follows: seedling height is Toronto 54.17 cm,Quebec 33.91 cm,Winnipeg 24.76cm;diameter is Toronto 6.32 mm,Quebec 5.41 mm,5.13 mm Winnipeg.Its growth vigor is significantly better than the other 3 plots.Combined with the comparison of the natural environment and soil properties among the 4 plots.The introduction of sugar maple in Shucheng plot more successful than plot.（3）High temperature is the limiting factor of introduction Canadian sugar maple.After 3 days stress with 27℃,33℃,39℃,45℃temperature gradient,leaf injury degree,the relative conductivity and the source MDA content increased with the increase of temperature;leaf Pro content of sugar maple from Winnipeg decreased in the 45 temperature stress,while the content of Pro from Toronto and Quebec has been increased;and the activity of POD from three provenances started to decline at 39 ℃,but the decline extent is different.After stress with 45 ℃,leaf damage degree and the relative conductivity of sugar maple from Toronto decreased by 34.12%,42.08%,respectively;the increase extent of content of MDA is smallest while content of Pro most.The content of MDA is 3.67 times that of the control group and content of MDA 12.57 times,respectively;The activity of POD of southern was always higher than that of Quebec and Winnipeg among four temperature gradient stress;According to the changes of these indexes,we conclude that: the order of the heat resistance of sugar maple from different provenances is: Toronto> Quebec>Winnipeg.（4）Study on the day of diurnal variation of photosynthesis of sugar maple from three provenances under the natural high temperature on August showed that the change of net photosynthetic rate of sugar maple are double-peak curve and net photosynthetic rate decreases sharply at noon,There was obvious photosynthetic midday depression.Photosynthesis was positively correlated with stomatal conductance and negatively correlated inter cellular CO₂ concentration.The diurnal variation of transpiration rate presented a single-peak curve,but the peak appeared at different time.The specific values of net photosynthetic rate of sugar maple from three provenances in the summer with high temperature was low.The maximum value（Toronto）that appeared at about 10:30 am,was merely 3.22 mol/（m2.s）;but net photosynthetic rate of sugar maple from Toronto was higher than the other two kinds of sugar maple in diurnal variation.The conclusion is that: the high temperature in summer has a certain influence on the growth of sugar maple from three provenances;Growth adaptability of sugar maple from Toronto in summer is stronger than the other two provenances of sugar maple.