In situ hybridisation applied to chromosomes of Anacamptis morio. Blue DAPI staining shows chromosomal DNA (
C); red and green signals show sites of hybridisation of 18S-25S rDNA and 5S rDNA respectively (A, D, B, E). Arrows indicate sites. Mitotic metaphase 2n = 2x = 36 with (A) six 18S-25S rDNA sites and (B) two 5S rDNA sites. Mitotic metaphase 2n = 3x = 54 with (D) nine 18S-25S rDNA sites and (E) three 5S rDNA sites. Interestingly, a large number of 18S-5.8S-25S rDNA sites (9) were observed in interphase nuclei (small arrow).