Wang, J., Du, W., Wu, J., Chen, X., Liu, C., Zhao, J., Yang, Q. and Li, F. 2014. Development of a specific SCAR marker for the Ns genome of Psathyrostachys huashanica Keng. Can. J. Plant Sci. 94: 1441-1447. Psathyrostachys huashanica Keng (2n=2×=14, NsNs) possesses many agronomically desirable traits that could be used in wheat improvement. We have previously produced a complete set of wheat-P. huashanica disomic addition lines (1Ns-7Ns, 2n=44=22 II). To track the addition of P. huashanica chromatin in wheat rapidly and effectively, a repetitive sequence of 1665 base pairs, designated pHs8, was isolated based on 21 different Triticeae species, including the parents' common wheat cv. 7182 and P. huashanica, by RAPD analysis. The diagnostic fragments of the RAPD marker OPF15₁₆₆₅ were cloned, sequenced, and converted into a sequence-characterized amplified region (SCAR) marker, known as RHS12. Southern hybridization using labeled pHs8 as probe showed intense hybridization signals on P. huashanica, but not on the other 20 species at all. RHS12 was validated using 21 different plant species and a complete set of wheat-P. huashanica disomic addition lines. Our results indicated that the SCAR marker targeted the Ns genome of P. huashanica and it was present in all seven P. huashanica chromosomes. The newly developed SCAR marker should help wheat breeders to screen for genotypes containing P. huashanica chromatin with low costs and high throughput.