基于SSR标记的文冠果遗传多样性分析及指纹图谱构建OA北大核心CSTPCD

[Objective]This work aims to quickly identify and utilize Xanthoceras sorbifolia germplasm resources,and explore the relationship of germplasm.[Method]Eleven primers with clear bands and good polymorphism were selected from 20 pairs of SSR primers.Fluorescence capillary electrophoresis technology was used for 29 X.sorbifolia varieties(lines)polymorphism detection.The neighbor-joining method was utilized for cluster analysis,while numerical and letter codes were assigned to create molecular identity cards.[Result]A total of 66 alleles were detected,and each pair of primers detected 3-10 alleles with an average of 6.The Shannon information index(I)varied from 1.723 to 0.349,with an average of 1.16.The polymorphic information content(PIC)revealed by different primers ranged from 0.276 to 0.841,with an average of 0.66.The observed heterozygosity(Ho)ranged from 0.137 to 0.958,with an average of 0.739.The expected heterozygosity(He)ranged from 0.187 to 0.79,with an average of 0.648.Among the 11 loci,7 loci had an average observed heterozygosity greater than the average expected heterozygosity.The genetic diversity coefficient varied from 0 to 1 with an average of 0.31.There were 15 individuals with a genetic similarity coefficient above 0.6,accounting for only 5.17%of the total data.At the genetic distance of 0.42,the 29 X.sorbifolia materials were divided into three categories by cluster analysis.Based on these results,the DNA fingerprint database composed of the digits 0 and 1 and the molecular identity card were established,which allowed unequivocal identification of all the varieties except a few unique ones.[Conclusion]This indicates that the genetic diversity of the 29 germplasm resources of X.sorbifolia is relatively high,but there is also a certain degree of inbreeding.Molecular identity cards for X.sorbifolia using SSR markers is simple and feasible,which may provide technical support and scientific basis for genetic identification,rights protection,identity validation,traceability management,and new variety breeding of X.sorbifolia varieties.