Genetic diversity in white clover and its progenitors as revealed by DNA fingerprinting

Abstract

The genetic diversity and ancestral relationships of a number of Trifolium species was revealed by using the amplified fragment length polymorphism (AFLP) and the random amplified polymorphic DNA (RAPD) markers. Both markers produced few species-specific markers. Using distance and parsimony methods, in NTSYS-pc and PAUP software programs, we clearly differentiated the accessions of white clover from other closely related progenitors. The phylogenetic trees, produced by PAUP, also reinforced the close affinity of T. nigrescens and the allopolyploid white clover in support of former views that this diploid species could have been the donor of one of two genomes of the allotetraploid T. repens. In addition, the dendrograms, produced by NTSYS-pc, also indicated close affinity of T. nigrescens and T. occidentale to the accessions of T. repens. These data is congruent with karyological and phylogenetic affinities between the white clover and T. occidentale. The relationships between the examined accessions, in the T. repens gene pool, may be regarded to indicate the presence of shared alleles between T. repens, T. occidentale and T. uniflorum. Further, T. occidentale showed close phylogenetic relations to T. pallescens.

Genetic variability evaluation and cultivar identification of tetraploid annual ryegrass using SSR markers

“…DNA-based molecular markers have provided a powerful method for genetic diversity assessment (Badr, El-Shazly & Mekki, 2012; Srinivas et al, 2012) and cultivar identification (Anand, Prabhu & Singh, 2012; Karaagac et al, 2014). Although genetic diversity of ryegrass accessions have been evaluated by amplified fragment length polymorphism (AFLP) (Guthridge et al, 2001), restricted fragment length polymorphisms (RFLP) (Sato et al, 1995), sequence-related amplified polymorphism (SRAP) (Huang et al, 2014a; Huang et al, 2014b) and randomly amplified polymorphic DNA (RAPD) (Bolaric et al, 2005; Vieira et al, 2004), simple sequence repeat (SSR) markers are still considered as a powerful tool for characterizing the genetic variability of cultivars.…”

“…Nevertheless, with bulking strategies, the loci had to be filtered for suitable estimation of allele frequencies. Many previous studies on genetic diversity evaluation and cultivar identification of outcrossing plants were carried out using single bulk strategy without replications, which induced unstable results for its application (Badr, El-Shazly & Mekki, 2012; Jiang et al, 2013). Furthermore, although bulking DNA samples has been successfully applied in several plant species to distinguish cultivars and to study genetic diversity (Tehrani et al, 2009; Herrmann, Flajoulot & Julier, 2010; Dubreuil et al, 2006; Jiang et al, 2013; Kölliker et al, 2001), a comparison study is necessary to identify optimal sampling strategies and to select informative loci.…”