Cytogenetic and Molecular Marker-Based Characterization of a Wheat-Psathyrostachys huashanica Keng 2Ns(2D) Substitution Line

Wheat- Psathyrostachys huashanica Keng substitution line 16-6, which possessed superior numbers of florets and kernels per spike, was developed from a cross between common wheat cv. 7182 and P. huashanica via embryo culture. This line was characterized based on cytological, genomic in situ hybridization (GISH), simple sequence repeat (SSR), fluorescent in situ hybridization (FISH), expressed sequence tag-sequence-tagged site (EST-STS), and morphological analyses. Line 16-6 contained 21 bivalents during meiosis, while GISH studies detected an alien chromosome pair substitution. Sixteen microsatellite markers for chromosome arms 2DS and 2DL of hexaploid wheat and FISH using the probe pAs1 indicated that chromosome 2D was missing. P. huashanica 2Ns(2D) chromosome introgression was confirmed using 780 EST-STS multiple-loci markers that covered all seven homoeologous groups and 14 EST-STS markers associated with homoeologous group 2 of wheat. After inoculation using mixed races of stripe rust (CYR31, CYR32, and SY11-14) in the adult stages, line 16-6 exhibited resistance, which was derived from the donor species. Compared with the control, the spike length, number of spikelets per spike, and kernel number per spike were significantly higher.