Detection of the Ribosomal RNA Gene in Pear (Pyrus spp.) using Fluorescence in situ Hybridization

Abstract

The locations of the 18S-5.8S-25S ribosomal RNA gene (rDNA) in the seedlings of Japanese pear [Pyrus pyrifolia (Burm. F.) Nakai] ‘Osa Gold’ and European pear (P. communis L.) ‘La France’ and the 18S ribosomal rDNA in ‘Osa Gold’ were determined using fluorescence in situ hybridization (FISH). 18S-5.8S-25S and 18S rDNA probes were labeled with biotin-16-dUTP. The probes were detected using a fluorescein isothiocyanate (FITC)-avidin conjugate with chromosomes counterstained with propidium iodide (PI). The 18S-5.8S-25S and 18S rDNA sites of ‘Osa Gold’ and the former of ‘La France’ were detected in telomeric positions of six chromosomes. The number and positions of rDNA sites were stable.