LAUSR

Fluorescence in situ hybridization (FISH) has been widely used to analyze the physical mapping of chromosomes and study the chromosome rearrangements during evolution. The conventional FISH technique is time-consuming and labor-intensive as it involves many experimental steps including (1) PCR amplification of the target sequence, (2) recovery of the amplified product, (3) plasmid extraction, (4) fluorescence labeling, as well as (5) denaturing of chromosomes and probes. Here we report an effective method for the design of oligonucleotide probes and the development of a new oligonucleotide probe for non-denaturing FISH in barley. The probe Oligo-442A01 with 6133 copies in barley genome could be mapped to the subtelomeres of barley. However, there were significant differences in signal positions and strengths between Oligo-442A01 and the contrast probe Oligo-HvT01.1, especially on chromosome 3H. These oligonucleotide probes combinations (AGG)5 and Oligo-442A01, (CTT)5 and Oligo-HvT01.1 could effectively differentiate the barley chromosomes.