Cryptic Introgression of Dasypyrum villosum Parental DNA in Wheat Lines Derived from Intergeneric Hybridization

Cytogenetic and DNA molecular analyses have been carried out in 3 wheat introgression lines (ILs; CS x V58, CS x V59, and CS x V60) derived from Triticum aestivum cv. 'Chinese Spring' (CS) x Dasypyrum villosum (Dv) intergeneric hybridization. All lines, which showed several phenotypic differences compared to CS, had the same chromosome number (2n = 42) and structure as CS, and neither chromosomes nor chromatin from Dv were apparently added to their complement. However, Feulgen/DNA cytophotometry showed that there was more nuclear DNA in the lines than in the parental wheat (by 1.85%, 2.76%, and 1.26% in CS x V58, CS x V59, and CS x V60, respectively). Molecular investigation indicated the presence of Dv DNA in the ILs. AFLP analysis of genomic DNA from the ILs, CS, and Dv detected a total of 120 polymorphic bands, of which 7 (5.8%) were present in some or all the ILs and Dv but were absent in CS. PCR amplification, sequence analysis of amplicons, and Southern blot hybridization confirmed the presence of Dv-specific sequences in each of the ILs. These results indicate cryptic introgression of Dv DNA sequences into the genome of the ILs. Some implications of this finding are discussed. Copyright (C) 2011 S. Karger AG, Basel