Genetic variation of white clover varieties detected by inter-SSR fingerprinting

Abstract

The DNA profiles of the varieties tested were found to posses 130 fragments, of which 43 were polymorphic. The sizes of amplified fragments varied from 300bp to 2500bp. Most of the simple repeat sequence primers (59.1%) generated DNA profiles of 1-2 types. A greater genetic diversity of the varieties was revealed using di- (AC)8G, (CA)7GA, (CT)8A, (GA)8C, (TC)8C and tri-nucleotide motif (GAA)5CG primers. These primers generated formation of 6-8 types of DNA profiles in the clover varieties. Replacement of the ‘anchor’ in the primers possessing GACA, GAA, CTC, AC nucleotide sequences had some effect on the number of DNA fragments and their size. Genetic similarity coefficient calculated according to DNR profiles varied within 0.57-0.86 range. Genetic similarity of the varieties Bitūnai, Nora and Sūduviai characterised by similar leaf, petiole and stolon parameters, re-growth rate, number of inflorescences and resistance to clover canker causal agent, varied from 0.80 to 0.86. Genetic similarity value of the varieties Bitūnai (hollandicum) and Regal (giganteum) belonging to different clover strains was 0.57. Genetic similarity coefficient among the varieties characterised by different overwinter survival, re-growth rate, earliness and other characteristics (Sūduviai and Ramona, Regal, Ross, and Ramona and Nora), varied from 0.60 to 0.66.