Physical mapping of ribosomal DNA sites in Festuca arundinacea and related species by in situ hybridization

Abstract

Festuca, in situ hybridization, phylogeny, physical mapping, rDNA.

An Increasing Need for Productive and Stress Resilient Festulolium Amphiploids: What Can Be Learnt from the Stable Genomic Composition of Festuca pratensis subsp. apennina (De Not.) Hegi?

“…Frontiers in Environmental Science | www.frontiersin.orgwith previous results of Thomas et al (1997) and Kopecký et al (2008a). In F. apennina, four 45S rDNA loci were detected on two pairs of chromosomes.…”

“…Probes for 5S rDNA and 45S rDNA were prepared as described in Thomas et al (1997). The rDNA probes were used in an initial FISH experiment with triploid, tetraploid, and pentaploid cytotypes and their possible progenitors represented by F. arundinacea Bn 950 and F. pratensis Bf 970.…”

Introgression of crown rust (Puccinia coronata) resistance from meadow fescue (Festuca pratensis) into Italian ryegrass (Lolium multiflorum) and physical mapping of the locus

“…The Fp DNA was combined with unlabelled Lolium DNA in the ratio 1:40. The clone pTa71, which contains the 18S-5.8S-26S rDNA gene cluster, was labelled with dig-11-dUTP and incorporated into the hybridisation mixture to help identify individual chromosomes (Thomas et al, 1997); this hybridises to the Lolium and Festuca rDNA sites. Slides were examined using a Leica DM/RB epifluorescence microscope with filters for DAPI, fluorescein and rhodamine.…”

Introgression mapping in the grasses. II. Meiotic analysis of the Lolium perenne/Festuca pratensis triploid hybrid

“…The ease of hybridization, the high frequency of homoeologous chromosome pairing observed at meiosis in both diploid and triploid hybrids and a preliminary molecular genetic study on the phylogeny of these species (Stammers et al, 1995) indicate that they are closely related. In contrast, the sterility of the diploid hybrid, the ease with which Lp and Fp chromosomes can be distinguished using genomic in situ hybridization (GISH) (King et al, 1997(King et al, , 1998 and the position and number of rDNA sites in the two species (Thomas et al, 1996(Thomas et al, , 1997a indicates that they are distantly related. Thus, the relationship between Lp and Fp remains a paradox at present.…”