Development of an oligonucleotide dye solution facilitates high throughput and cost-efficient chromosome identification in peanut

Background: Development of oligonucleotide probes facilitates chromosome identification via fluorescence in situ hybridization (FISH) in many organisms.

Results: We report a high throughput and economical method of chromosome identification based on the development of a dye solution containing 2 × saline-sodium citrate (SSC) and oligonucleotide probes. Based on the concentration, staining time, and sequence effects of oligonucleotides, an efficient probe dye of peanut was developed for chromosome identification. To validate the effects of this solution, 200 slides derived from 21 accessions of the cultivated peanut and 30 wild Arachis species were painted to identify Arachis genomes and establish karyotypes. The results showed that one jar of dye could be used to paint 10 chromosome preparations and recycled at least 10 times to efficiently dye more than 100 slides. The A, B, K, F, E, and H genomes showed unique staining karyotype patterns and signal colors.

Conclusions: Based on the karyotype patterns of Arachis genomes, we revealed the relationships among the A, B, K, F, E, and H genomes in genus Arachis, and demonstrated the potential for adoption of this oligonucleotide dye solution in practice.