Isolation of a chromosomally engineered durum wheat line carrying the Aegilops ventricosa Pch1 gene for resistance to eyespot

The chromosome 7D(v) of Aegilops ventricosa (syn. Triticum ventricosum, 2n = 4x = 28, genome (DDMMv)-D-v-M-v-M-v) carries the gene Pch1 for resistance to eyespot. This gene has previously been transferred to chromosome 7D of bread wheat, T. aestivum (2n = 6x = 42, genome AABBDD). To (1) enhance the level of resistance of bread wheat by increasing the copy number of Pch1, a nd (2) create eyespot-resistant triticales, meiotically stable Pch1-carryin g durum lines were selected from the backcross progenies of a cross between Ae. ventricosa and T. durum cv. Creso ph1c (2n = 4x = 28, genome AABB). Th e Pch1 transfer, likely resulting from homoeologous recombination, was loca ted at the distal position on the long arm of chromosome 7A. The 7A microsa tellite marker Xgwm 698 was found closely linked in repulsion to the introg ression in the resistant recombination lines, and the endopeptidase allele located on chromosome 7A of cv. Creso ph1c was lost.