Plant Genome III Conference Plant Genome III Conference
Among the three ancestal A, B and D genomes of bread wheat, the D genome is the least modified and almost completely homologous to genome of the diploid donor Triticum tauschii (2n=14). The D genome is a readily available source of resistance and other useful genes that can be rapidly transferred to wheat by direct hexaploid x diploid crosses. Genetic analysis and tagging of useful genes can be carried out in T. tauschii to enhance efficiency and precision of their transfer to bread wheat. Moreover, T tauschii is ideal for RFLP mapping because of simple diploid inheritance and a high degree of polymorphism even among different accessions. Because of these favorable attributes, we are constructing a high density diploid genetic linkage of wheat based on T. tauschii. So far we have mapped 318 probes from wheat, barley, and oats which detect 440 loci. We have selected 260 loci that segregate 1:2:1 to make an anchor map. The remaining probes will be mapped in reference to these markers. The basic wheat linkage map and comparative maps among wheat, barley and oats for individual chromosomes will be presented.