Screening of Brassica napus core SSR primers

In order to find a set of SSR core primers for purity identification and genetic diversity research on rapeseed,746 SSR primers were screened using 100 representative materials of Brassica napus L.collected from different areas of China.44 primers were selected according to PIC(polymorphism information content) value,reproducibility,patterns and distribution on genome.Among them,20 were determined as preferred core primers,others were candidate core primers.There were 3 to 9 alleles amplified by each pair of preferred primers with PIC values range from 0.56 to 0.80.A total of 102 polymorphism alleles were detected by the preferred SSR core primers.They covered 11 linkage groups of B.napus.The effectiveness of core primers on purity identification and cultivar protection was tested on a randomly selected hybrid F1.Consistent result was obtained between amplification and field identification even by a randomly chosen core primer.And the primer was able to identify the seed from non-female parent.Results from genetic clustering and family origin assay also showed the validity of the core primers for germplasm diversity analysis.