Study On The Introduction And Eco-physiology Characteristics Of Rhododendron Fortunei

The original habitate ecological environment,the comparison of introduction ways and three production ways,the survay of the height and diameter of Rhododendron fortunei were investigated in this paper.The eco-physiological targets were measured by the advanced photosynthesis determination system.The grow environment,the introduction methods,the grow situation and the physiological characteristic in different seasons and different ecological environment of Rhododendron fortunei were studided.The results showed as following:1.The Rhododendron fortunei grew best along the rill,and the elevation is about 900 meters in the southeast of the mountain.The mature trees were growing well,flowers and seeds were well too,moreover,there were many seedlings.2.2 years old Rhododendron fortunei had the heighest survival rate,grew best,and had the strongest compatibility for introduction.The survival rate had reached 95%.3.Both the net photosynthetic rate(Pn)and transpiration rate(Tr)of 3 years old Rhododendron fortunei were slightly higher than 6 years old seedlings in spring.The average Pn and Tr of 3 years old Rhododendron fortunei were far higher than 6 years old seedlings in summer and autumn.The curve of diurnal variation of Pn of Rhododendron fortunei seedlings were single-peaked curwe in winter.The Pn of 3 years old Rhododendron fortunei was slightly higher than 6 years old seedling,but the Tr of both 3 years old and 6 years old seedlings are unstable in winter,assume the irregular curve.The curve of diurnal variation of Pn and Tr of mature trees and 5 years old seedlings were single-peaked.The Pn and Tr of mature trees were higher than 5 years old seedlings before 12:00,on the opposite,both the Pn and Tr of 5 years old seedlings were slightly higher than mature trees after 12:00.Under the visor,the Pn of both 3 years old and 6 years old Rhododendron fortunei seedlings were smaller and increased slower than under the entire illumination at 8:00 to 9:00 in summer and autumn,but after 9:00,the Pn of seedlings under the visor increased quicker and surpass the seedlings under the entire illumination.The "Midday rest" of seedlings were not obvious under visor conditions in summer,but it was obvious under entire illumination.The curve of diurnal variation Pn of both 3 years old seedlings and 6 years old seedlings were single-peaked,but the Pn of of both 3 years old seedlings and 6 years old seedlings were higher under visor than under the entire illumination.The curve of Tr of both 3 years old and 6 years old Rhododendron fortunei were single-pincked curve under entire illumination and under visor in summer and autumn.The Tr of 6 years old Rhododendron fortunei were higher under visor than under entire illumination.Regress analysis showed that the most significant factors affecting Pn changes were stomatal conduction(Cond),followed by ecological factors such as PAR,Ci,Tair and RH etc.The most significant factors affecting Tr changes were stomatal conduction(Cond)and CO₂ concentration in cell clearance(Ci),followed by ecological factors such as Tair,Tleaf, PAR and RH etc.4.The content of chlorophyll was highest in summer,the next was spring,then was autumn and winter.The change of Pn was simillar to the content of chlorophyll.The Pn was fastest in summer,the next was in spring,then was in autumn and winter.The change of chlorophyll a/b was:It was higher at spring and autumn,and it was lowest in summer, when the chlorophyll at maximize,the chlorophyll a/b was at the lowest.Along with the leaves grew older,the chlorophyll a/b gradually rised,it was highest in winter.