The F
1 hybrids from crosses of 59 accessions of wild and cultivated
Triticum types including amphidiploids
T. boeoticum-Ae. squarrosa, T. timopheevi-Ae. squarrosa, T. timopheevi-T. monococcum, T. boeoticum (4n),
T. macha, and
T. Zhukovskyi with
T. durum Sel. 56-1 and/or
T. aestivum were examined for male sterility and chromosome pairing at metaphase I of meiosis in pollen mother cells. Those hybrids which produced male-sterile F
1's were recurrently backrossed with pollen from
T. durum or
T. aestivum to study segregation for male sterility and/or to confirm cytoplasmic male sterility.
All T. timopheevi and T. araraticum accessions and several T. dicoccoides types, including T. dicoccoides var. nudiglumis from the Turkey-Iran-Iraq area, had male sterility inducing cytoplasm. The chromosome pairing in the F1 hybrids indicated that all tetraploid Triticum accessions with male sterility inducing cytoplasm had genome AAGG. T. dicoccoides
Körn types from the Turkey-Iran-Iraq area had genomes AABB and did not have male sterility inducing cytoplasm. Therefore, T. dicoccoides
Körn and the T. timopheevi complex differ from each other cytoplasmically and cytogenetically and occur sympatrically in the Turkey-Iran-Iraq area.
Possibly, the cytoplasm of the emmers was not derived from the putative diploid progenitors, T. boeoticum, Ae. speltoides, or Ae. bicornis as indicated by their nucleo-cytoplasmic and cytogenetic relationships with the tetraploid Triticum species. The cytoplasmic differences among Ae. speltoides, T. araraticum and T. timopheevi are of a relatively smaller magnitude than the cytoplasmic differences among T. timopheevi, T. boeoticum, and the emmers. A complete analysis of nucleo-cytoplasmic relationships among Triticum and Aegilops species may indicate the cytoplasmic donor(s) to the two tetraploid Triticum species complexes.
Authorized for publication 19 July, 1972 as Paper No 397 in the Journal Series of the North Dakota Agricultural Experiment Stations.