Genetic Relations Analysis of 21 Zizyphus mauritianas by ISSR Markers
A genetic analysis of 21 diverse Zizyphus mauritiana accessions was performed using ISSR marker.The orthogonal design was used to optimize the ISSR-PCR amplification system on Z.mauritiana.The optimal components of the PCR system(25 μL)were: 2.5 μL of 10×PCR buffer,3.75 μL of 2.5 mmol/L dNTPs,1.5 μL of 0.5 U/μL TaqDNA ploymerase,1.5 μL of 5 μm/L primer,0.75 μL of 100 ng/μL DNA and 15 μL ddH2O2.Twenty-one Z.mauritiana species were classified by ISSR makers.Thirteen primers were selected from 100 primers and used for ISSR amplification.Ninety-eight bands were generated,78 of which were polymorphic bands(the percentage of polymorphic band,PPB=85.7%).The genetic similarity coefficient was 0.51 to 0.90 according to ISSR amplification.The clustering dendrogram was constructed by UPGMA method to explore the taxonomic relationship in 21 Z.mauritiana materials.At 0.67 level of similarity coefficient,the 21 Z.mauritiana materials were classified as three groups: groupⅠ: var.Misi;groupⅡ: 17 varieties from Taiwan;group Ⅲ: var.Diancizao,var.Miandianyuanguo and var.Miandianchangguo.The similarity coefficient was above 0.67 level in most varieties,suggesting that the genetic diversity was low in the 21 Z.mauritiana species.were above 0.67 level in most varieties,suggested that genetic diversity was low in 21 Zizyphus mauritiana species.