The Research On High Temperature And Off-season Transplanting Technology Of Two Kinds Of Magnolia Trees

The research mainly focuses on Michelia chapensis Dandy and Magnolia denudata Desr.’Fei Huang’ which are widely used for garden planting in recent years,It finally outlined the influence of different transplanting measures such as soil ball size, shedding defoliation, watering, shading screen, also the use of antitranspirant upon survival rate and growth vigour after transplanting under out-of-season and in high-temperature. On the other hand, it mensurated the shedding defoliation and the change of photosynthesis, physiology and biochemistry, growth target of the two species when transplanted under out-of-season and in high-temperature, so could study their capacity of high-temperature-resistant and drought-resistant. In this way, we could provide some reference for improving survival rate of trees of garden planting under out-of-season and in high-temperature, and also could enhance growth vigour after transplantations.1Michelia chapensi Dandys’s survival rate is the highest and grows well, on condition that temperature is below28℃, transplanted soil is fertile, shedding defoliation is55%～70%, soil ball is10-12times of DBH, watering is2times per day and shading50%. Its survival rate is the lowest on condition that temperature is upon30℃, transplanted soil is poor, thinning defoliation is more than70%or less than55%, soil ball is less than8times of DBH, watering is less than1times per day and no shade. Among others, the use of antitranspirant does not have a notable impact on its survival rate.The survival rate of Magnolia denudata Desr.’Fei Huang’ is the highest on the condition that sheddning defoliation is between55%and85%and soil ball is8～10times of DBH. But the technical measures such as temperature, soil fertility, shading and antitranspirant have slight impact on its survival rate.2The scale of Shedding defoliation has a notable impact on the survival rate of Michelia chapensis Dandy but not on Magnolia denudata Desr.’Fei Huang’ when they were transplanted under out-of-season and in high-temperature. The survival rate of Magnolia denudata Desr.’Fei Huang’ is higher than Michelia chapensi Dandy on the condition that the same shedding defoliation, no matter which kind of pattern of picking leaves.(1) With the increasing high temperature and the days of growth after transplanting, the leaf of the two specimen’s relative conductivity,POD activity, the content of soluble protein and MDA increased in varying degrees, while leaf relative water content decreases in the converse way. Their MDA relative conductivity,POD activity, the content of soluble protein are decreased more than expected after transplanting60d, but the index of leaf relative water content, the content of soluble protein increased with the days elapsed, there is no big difference between the indicators of the two similar species, indicators are not fully in the same line during the variation, more changes can be observed in period of half leaves’s range.(2) While the two species were transplanted under high temperature later, there is no regularity in the content of total chlorophyll and chlorophyll a/b However, after transplanted25d later, decreasing of the content of total chlorophyll is changed more obvious with the different treatmentsAfter transplanted later,the two species photosynthetic rate,transpiration rate, stomatal conductance decreased on varying scale, the half leaves’s even has a sharp drop.the two species have different levels of light saturation point reduction, which the whole leaves’s saturation is lower than the half leaves’s.With the same shedding defoliation, Michelia chapensi Dandys’s survival rate of no picking is higher than the one of picking half leaves. And its survival rate is the highest that the average survival is more than90percent on the conditiong that shedding defoliation is between55-77%. After transplanting,70%whole leaves capacity has the high temperature resistance and drought tolerance, as well as growth vigour. The survival rate is lower when sheddinging defoliation between0%and100%, it grows worse. The use of antitranspirant not only does not improve the survival rate when the shedding defoliation is55%and whole leaves, but also causes its leaves fall off easily and grow bad.When shedding defoliation is the same, the survival rate of Magnolia denudata Desr.’Fei Huang’ of half leaves is higher than the one of full size. Its survival rate is the highest that the average survival is more than90%on the condition of between55%-85%. after transplanting,55%half leaves’s capacity of high temperature resistance and drought tolerance are better,And its survival rate is70%when shedding defoliation is0%. The use of antitranspirant has no notable impact on the survival rate when whole leaves’s shedding defoliation is55%and its growth turned worse after transplanted, the leaves turned yellow quickly and fell off early.