title: Additional evidence implicating Triticum searsii as the B-genome donor to wheat.
abstract: In vitro DNA:DNA hybridizations and hydroxyapatite thermal-elution chromatography were employed to identify the diploid wheat species ancestral to the B genome of Triticum turgidum. 3H-T. turgidum DNA was hybridized to the unlabeled DNAs of T. urartu, T. speltoides, T. sharonensis, T. bicorne, T. longissimum, and T. searsii. 3H-Labeled DNAs of T. monococcum and a synthetic tetraploid AADD were hybridized with unlabeled DNAs of T. urartu and T. searsii to determine the relationship of the A genome of polyploid wheat and T. urartu. The heteroduplex thermal stabilities indicated that T. searsii was most closely related to the B genome of T. turgidum (AB) and that the genome of T. urartu and the A genome have a great deal of base-sequence homology. Thus, it appears that T. searsii is the B-genome donor to polyploid wheat or a major chromosome donor if the B genome is polyphyletic in origin.
mesh_terms: D005075:Biological Evolution; D004247:DNA / Q000235:genetics* / Q000302:isolation & purification; D004171:Diploidy; D005796:Genes; D009693:Nucleic Acid Hybridization; D009695:Nucleic Acid Renaturation; D010944:Plants / Q000235:genetics*; D013045:Species Specificity; D013816:Thermodynamics; D014908:Triticum / Q000235:genetics
chemical_list: D004247:DNA