Biodiv Sci ›› 2009, Vol. 17 ›› Issue (5): 482-489.  DOI: 10.3724/SP.J.1003.2009.09074

• Editorial • Previous Articles     Next Articles

Genetic diversity in Chinese rapeseed (Brassica napus) cultivars based on EST-SSR markers

Lichuan Dai, Minglong Zhang, Jiye Liu, Xiaobai Li, Hairui Cui()   

  1. Laboratory of Nuclear Agricultural Sciences, Agricultural Ministry, Institute of Nuclear and Agricultural Sciences, Zhejiang University, Hangzhou 310029
  • Received:2009-03-31 Accepted:2009-07-02 Online:2009-09-20 Published:2009-09-20
  • Contact: Hairui Cui


In order to assess genetic variation in Chinese rapeseed (Brassica napus), the genetic diversity of 91 cultivars released in recent years was assessed using EST-SSR markers. In total, 100 amplified fragments were detected using 16 EST-SSR primer pairs; of these fragments 84 were polymorphic. The number of amplified and polymorphic fragments was 6.25 and 5.25 per primer pair, respectively. The PIC (polymorphism information content) value of these markers varied from 0.022 to 0.926, averaging 0.677. The genotypes revealed by each marker ranged from 2 to 24 with average of 12.44. Genetic distance (GD) varied widely, from 0.0530 to 0.7223, suggesting the presence of broad genetic variation in the accessions we used. Diversity was higher in hybrid varieties and varieties released after the year 2000 than in traditional open-pollinated varieties and varieties released before or during the year 2000, respectively. At GD = 0.313 the tested varieties could be classified into three groups clustered by UPGMA, in which the first group containing 87 cultivars could be further divided into 10 sub-groups at GD = 0.223. The cluster results generally agreed with pedigree analysis and reveal the true genetic variation in the materials tested.

Key words: Brassica napus, EST-SSR, polymorphism, genetic distance, cluster analysis