Root tip metaphase from a wheat plant with one pair of chromosomes from Aegilops umbellulata substituting for wheat chromosomes. This line has chromosome 1U present (pink), but the end of the short arm is deleted, with the rDNA loci. The green signal shows a repetitive sequence, pSc119.2, which assists with chromosome identification. For more details, See Xana Castilho et al., Theor Appl Genet (1996) 93:816-825.

Genomic DNA used as a probe to identify the alien chromosomes in a metaphase of bread wheat ( Triticum aestivum ): genomic DNA labelled in red from Aegilops umbellulata labels the alien chromosome pair in red, while the repetitive DNA sequence originally isolated from rye, pSc119.2, labels sites on many chromosomes allowing their identification.

Wheat-Aegilops substitution line