Tree Genetics and Molecular Breeding 2012, Vol.2, No.2, 8
              
            
            
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                3.5 Statistical Methods
              
            
            
              Using ITS sequence of
            
            
              
                Pachysandra
              
            
            
              
                terminalis
              
            
            
              as a
            
            
              reference, the number of nucleotide substitutions was
            
            
              counted out based on the principle of using pair-wise
            
            
              comparison. Using one parameter model of Jukes and
            
            
              Cantor (1969) and two-parameter model of Kimura
            
            
              (1968) calculated the base substitution data.
            
            
              
                Authors’ Contributions
              
            
            
              XFW and NL were the persons who conducted experimental
            
            
              design and performances and XFW also finished the data
            
            
              analysis and wrote the manuscript. KSJ was principal investi-
            
            
              gator who conceived the project and supervised the experimental
            
            
              designing, data analyzing, and paper writing and revising. All
            
            
              authors have read and agreed the final context of manuscript.
            
            
              
                Acknowledgement
              
            
            
              This study was funded by the “Eleventh Five-Year” National
            
            
              Science and Technology Support Project (NO.2006BAD01A1403).
            
            
              The authors thanked Zhong- shan Botanical Garden of Chinese
            
            
              Academy of Sciences for providing plant materials.
            
            
              
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