New Insights Into the Introgression Between Agropyron Cristatum P Genome and Wheat Genome

Abstract Agropyron cristatum (2n = 4x = 28, PPPP) is an important wild relative of common wheat and confers desirable agronomic traits to common wheat. A previous report showed that the wheat-A. cristatum 6P translocation line WAT655 carrying A. cristatum 6PS (0.81–1.00) exhibited high resistance to prevalent physiological races (CYR32 and CYR33). In this study, three disease resistance-related transcriptomes, which were mapped to A. cristatum 6PS (0.81–1.00) through the analysis of specific molecular markers, were searched from among A. cristatum full-length transcriptomes. Then, three disease resistance-related gene markers, A. cristatum P genome-specific markers, and fluorescence in situ hybridization (FISH)/genomic in situ hybridization (GISH) probes made from the DNA of three bacterial artificial chromosome (BAC) clones, three genes, and A. cristatum “Z559” were used to analyze the BC5F2 and BC5F2:3 genetic populations of the translocation line WAT655. The results revealed the introgression can spontaneously occur between A. cristatum P genome and wheat genome, and indicated the three genes could constitute a gene cluster according to the positions of their FISH signals. Additionally, kompetitive allele-specific PCR (KASP) markers of the three genes were developed to detect and acquire 24 wheat-A. cristatum breeding materials, which showed resistance to physiological races (CYR32 and CYR33) and other desirable agronomic traits according to the field investigation. In conclusion, our study not only provides new insights into the introgression between A. cristatum P genome and wheat genome, but also provides the desirable breeding materials for breeding practice.