Evidence on the origin of the G genome in wheat: cytology and fertility of a T. timopheevi-like mutant

Abstract

A spontaneous somatic mutant with Triticum timopheevi Zhuk. plant morphology was found in late tillers of a Triticum turgidum L. var. dicoccoides (Bowden) plant. Hybrids of the timopheevi-like mutant with T. turgidum L. var. dicocooides (Bowden), T. timopheevi Zhuk., and T. araraticum Jakubz. exhibited irregular pairing at meiosis and sterility, almost normal pairing and fertility, and relatively high pairing and sterility, respectively. This evidence plus that of karyotype changes in the somatic mutant indicated that it was differentiated from T. turgidum dicoccoides through chromosome interchanges. This mutation, believed to arise through chromosome rearrangement, is discussed in relation to the origin of the G genome of T. timopheevi.

Chromosome constitution of polyploid wheats: Introduction of diploid wheat chromosome 4

“…Conclusive identification of a single species donor of the B gelnome has not been possible despite the analysis and promotion of a number of individual species, such as Aegilops bicornis Jaubert et Spach by Sears (5) (4), and Aegilops sharonsis Eig by Kushnir and Halloran (6). Alternatively, a more complex origin of the B genonie involving more than one species has been proposed.…”