Molecular and Cytogenetic Characterization of New Wheat-Dasypyrum breviaristatum Derivatives with Post-Harvest Re-Growth Habit.

A novel Dasypyrum species, Dasypyrum breviaristatum, serves as a valuable source of useful genes for wheat improvement. The development and characterization of new wheat-D. breviaristatum introgression lines is important to determine the novel gene(s) on specific chromosome(s). We first used multi-color fluorescence in situ hybridization (FISH) to identify the individual D. breviaristatum V(b) chromosomes in a common wheat-D. breviaristatum partial amphiploid, TDH-2. The FISH patterns of D. breviaristatum chromosomes were different from those of D. villosum chromosomes. Lines D2146 and D2150 were selected from a cross between wheat line MY11 and wheat-D. breviaristatum partial amphiploid TDH-2, and they were characterized by FISH and PCR-based molecular markers. We found that D2150 was a monosomic addition line for chromosome 5V(b) of D. breviaristatum, while D2146 had the 5V(b)L chromosome arm translocated with wheat chromosome 5AS. Molecular marker analysis confirmed that the introduced D. breviaristatum chromosome 5V(b)L translocation possessed a duplicated region homoeologous to 5AS, revealing that the 5AS.5V(b)L translocation may not functionally compensate well. The dwarfing and the pre-harvest re-growth habits observed in the wheat-D. breviaristatum chromosome 5V(b) derivatives may be useful for future development of perennial growth wheat lines.