A trial for chromosome identification in Agropyron cristatum

Said M., Cabrera A., Vrána J., Číhalíková J., Doležel J.
Plant Biotechnology: Green for Good III | 15 – 18 June | Olomouc - Czech Republic : , 2015

Abstract: Agropyron cristatum L. (Gaertn.) is a wild species that may provide novel genes for wheat improvement. The efforts to introgress chromosomes and chromosome segments of Agropyron into wheat would benefit from the ability to identify individual chromosomes of the species. Fluorescence in situ hybridization (FISH) with a set of probes on tetraploid accession of A. cristatum (2n=4x=28, PPPP) showed specific patterns for the majority of homologous chromosome groups. FISH with a probe for 45S rDNA revealed eight hybridization sites on four chromosome pairs, while the 5S rDNA probe revealed four sites of hybridization. Repetitive sequence pAs1 localized mostly in terminal regions of all chromosomes, and the pSc119.2 sequence was detected on sixteen chromosomes. The same probes were applied to six wheat-A. cristatum addition lines, each carrying one pair of A. cristatum chromosome (1P - 6P). FISH and GISH were also applied on chromosomes flow-sorted from the six wheat-A. cristatum addition lines. FISH with 45S rDNA revealed hybridization sites on terminal regions of the short arm of 5P, while 5S rDNA showed hybridization sites on sub-terminal region of the arm. This pattern allowed identification of chromosome 5P. In the six addition lines, 45S rDNA was detected only on homologous group 5P, indicating that chromosome 7P is the carrier of the remaining 45S rDNA sites. Unfortunately, wheat-A. cristatum chromosome 7P addition line has not been established yet. This work has been supported by the National Program of Sustainability I (award LO1204).
IEB authors: Jarmila Číhalíková, Jaroslav Doležel, Mahmoud Said, Jan Vrána