Analysis of chromosomal polymorphism in barley (Hordeum vulgare L. ssp. vulgare) and between H. vulgare and H. chilense using three-color fluorescence in situ hybridization (FISH)

Abstract

The aim of the present work was to study chromosomal polymorphism within cultivated barley (Hordeum vulgare ssp. vulgare) using three-color fluorescence in situ hybridization (FISH). The physical distribution of the most frequently used, highly repetitive DNA sequences (GAA)7 specific for pericentromeric heterochromatic regions, the ribosomal DNA clone pTa71, specific for the 45S rDNA, and the barley-specific telomere-associated sequence HvT01, was investigated to reveal genetic diversity in metaphase spreads of ten barley genotypes with diverse geographical origin, growth habit and row number. A wild relative of barley, Hordeum chilense was also studied in order to compare the polymorphism between and within Hordeum species. Significant differences in the hybridization patterns of all three DNA probes could be detected between the two related species, but only probes pTa71 and HvT01 showed variation in the intensity and/or position of hybridization sites among genotypes of H. vulgare ssp. vulgare. The extent of polymorphism was less than that earlier reported for molecular markers and was restricted to the long chromosome arms, with differences between the chromosomes. 1H and 3H proved to be the most variable chromosomes and 4H and 6H the most conserved.

Identification and comparison of individual chromosomes of threeHordeum chilenseaccessions,Hordeum vulgareandTriticum aestivumby FISH

“…4). Our results agreed with the results previously published in numerous cytological studies (Cabrera et al 1995; Szakács et al 2013; Delgado et al 2016).…”

“…Many of these repetitive sequences have been used as probes in FISH analysis for genome differentiation, phylogenetic relationship analysis and chromosome identification among different species of the Triticeae tribe (Cabrera et al 1995; Taketa et al 2000; Hagras et al 2005; Jiang and Gill 2006; Marín et al 2008; Cuadrado et al 2013; Komuro et al 2013). The identification and comparison of H. chilense and H. vulgare chromosomes have been carried out in several studies (Hagras et al 2005; Szakács et al 2013), however, only a small number of probes and one accession of H. chilense were used. For the comparison of both H. chilense and H. vulgare with bread wheat, there is barely any published studies where all individual chromosomes are targeted.…”

New Oligonucleotide Probes for ND-FISH Analysis to Identify Barley Chromosomes and to Investigate Polymorphisms of Wheat Chromosomes

“…Probe Oligo-pTa71-1 gave strong signals on the short arms of 5H and 6H chromosomes (Figure 1). The hybridization patterns of the probes (AAG) 6 , Oligo-HvT01 and Oligo-pTa71-1 on the chromosomes of cultivar CNSimai 1 are similar with the ones of (AAG) 7 , HVT01 and pTa71 on chromosomes of barley cultivar Igri [24]. …”

“…Repetitive DNA sequences including (AAG) n , HVT01 and pTa71 have been previously used as probes to analyze barley chromosomes by FISH methods [10,15,24,25,26]. These repetitive DNA sequences are useful in investigating the chromosomal structure of barley germplasm [10,15,24,25,26].…”

“…These repetitive DNA sequences are useful in investigating the chromosomal structure of barley germplasm [10,15,24,25,26]. In earlier studies, the procedure of the preparation of probes HVT01 and pTa71 was time-consuming because it involved denaturing the DNA of the chromosome spreads and also that of the labeled probes.…”