Analysis of Genetic Diversity of Chinese Cabbage by SRAP Markers

The SRAP analysis was conducted in order to investigate the blood relationship among the 46 Chinese cabbage inbred lines.8 primer pairs were selected from 170 primer pairs to amplify the genomic DNA.Totalling 328 SRAP fragments between 200 bp and 2 500 bp were obtained,and 283 of them were polymorphic markers.The polymorphic fragment percentage was 86.28%.The polymorphism information content was 0.3840.The effective number of alleles was 1.4170.The genetic dissimilarity of 46 Chinese cabbages was from 0.050 to 0.7553,and the average was 0.5508.Cluster analysis using UPGMA method showed that 46 inbred lines could be divided into five main groups.Three of them were high stake type;VB06-18 was a single group,and most short stake type belonged to the fifth group.The fifth group could also be divided into two sub-groups and spring materials were classified into one sub-group.The results showed the genetic background of heading Chinese cabbage was complex and the similarity of different materials in one group was high.Only by importing foreign germplasm resources at full blast and fully utilize primitive local variety,a breakthrough in Chinese cabbage breeding could be made.And the study results of this experiment had a certain role in guiding the work of cross-breeding of Chinese cabbage.