None of the diploid species of Triticum and Aegilops, from which tetraploid emmer and timopheevii wheats were presumably derived, presently possess a Ph gene identical to that on the long arm of chromosome 5B of T. aestivum. This suggests that the Ph gene originated at the tetraploid level. Both emmer and Timopheevii completely compensate for the absence of chromosome 5B of T. aestivum clearly due to the presence of a Ph gene identical to that on chromosome 5B. The presence of a similar Ph gene in both the tetraploids and its absence in the putative diploid parents suggests that the tetraploids diverged from a common amphiploid ancestor after the origin of the Ph gene. The possibility of independent origin of the tetraploids involving an unidentified common B genome donor with the Ph gene at the diploid level, however, can not be completely ruled out.
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References
Chapman, V., T.E. Miller & R. Riley (1976). Equivalence of the A genome of bread wheat and that of Triticum urartu. Genet. Res. Camb., 27: 69–76.
Chen, K., J.G. Gray & S.G. Wildman (1975). Fraction 1 protein and the origin of polyploid wheats. Science 190: 1304–1306.
Dhaliwal, H.S. (1976). Fertility and morphology of the synthetic amphiploids and the origin of tetraploid wheats. Cereal Res. Comm.. 4: 411–418.
Dhaliwal, H.S. & B.L. Johnson (1976). Anther morphology and the origin of the tetraploid wheats. Am. J. Bot. 63: 363–368.
Dover, G.A. & R. Riley (1972). Prevention of pairing of homoeologous meiotic chromosomes of wheat by an activity of supernumerary chromosomes of Aegilops. Nature Lond. 240: 159–161.
Feldman, M. (1966a) Identification of unpaired chromosomes in F1 hybrids involving Triticum aestivum and T. timopheevi. Can. J. Genet. Cytol. 8: 144–151.
Feldman, M. (1966b). The mechanism regulating pairing in Triticum timopheevi Wheat Inf. Serv. 22: 1–2.
Johnson, B.L. (1972). Protein electrophoretic profiles and the origin of the B genome of wheat. Proc. natn. Acad. Sci. U.S.A. 69: 1398–1402.
Johnson, B.L. (1975). Identification of the apparent B genome donor of wheat. Can. J. Genet. Cytol. 17: 21–39.
Kimber, G. (1973). The relationships of the S genome diploids to polyploid wheats. Proc. Fourth Int. Wheat Genet. Symp., Columbia, Missouri. pp. 81–85.
Kimber, G. & R.S. Athwal (1972). A reassessment of the course of evolution of wheat. Proc. natn. Acad. Sci. U.S.A. 69: 912–915.
Kostoff, D. (1936). The genomes of Triticum timopheevi Zhuk., Secale cereale L. and Haynaldia villosa Schr. Z. indukt. Abstamm.-u. Vererblehre 72 115–118.
Lilienfeld, F. & H. Kihara (1934), Genomanalyse bei Triticum und Aegilops. V. Triticum timopheevii Zhuk. Cytologia 6: 87–122.
Love, R.M. (1941). Chromosome behaviour in F1 wheat hybrids. I. Pentaploids. Can. J. Res. C 19: 351–369.
Okamoto, M. (1957). Asynaptic effect of chromosome V: Wheat Inf. Serv. 5: 6.
Rawal, K. & J.R. Harlan, (1975). Cytogenetic analysis of wild emmer populations from Turkey and Israel. Euphytica 24: 407–411.
Riley, R. (1960). The diploidization of polyploid wheat. Heredity 15: 407–429.
Riley, R., V. Chapman & G. Kimber (1960). Position of the gene determining the diploid like behavior of polyploid wheat. Nature Lond. 186: 259–260.
Riley, R. & C.N. Law. (1965). Genetic variation in chromosome pairing. Adv. Genet. 13: 57–114.
Riley, R., J. Unrau & V. Chapman (1958). Evidence on the origin of the B genome of wheat. J. Hered. 49: 91–99.
Sachs, L. (1953). Chromosome behaviour in species hybrids with Triticum timopheevi. Heredity 7: 49–58.
Sarkar, P. & G.L. Stebbins (1956). Morphological evidence concerning the origin of the B genome of wheat. Am. J. Bot. 43: 297–304.
Shands, H. & G. Kimber (1973). Reallocation of the genomes of Triticum timopheevi Zhuk. Proc. Fourth Int. Wheat Genet. Symp. Columbia, Missouri, pp. 101–108.
Tanaka, M. & S. Ichikawa (1972). Cytogenetical relationships of two types of Triticum araraticum Jakubz. to other tetraploid wheat species. Jap. J. Genet. 47: 103–114.
Tanaka, M. & H. Ishii (1973). Cytogenetical evidence on the speciation of wild tetraploid wheats collected in Iraq, Turkey, and Iran. Proc. Fourth Int. Wheat Genet. Symp. Columbia, Missouri, pp. 115–121.
Upadhya, M.D. & M.S. Swaminathan (1965). Studies on the origin of Triticum zhukovskyi and the mechanism regulating chromosome pairing. Ind. J. Genet. Pl. Breed 25: 1–13.
Wagenaar, E.B. (1966). Studies on the genome constitution of Triticum timopheevi Zhuk. II.Evidence for genetic control of meiotic irregularities in tetraploid hybrids. Can. J. Genet. Cytol. 3: 47–60.
Wagenaar, E.B. (1966). Studies on the genome constitution of Triticum timopheevi Zhuk. II. The T. timopheevi complex and its origin. Evolution 20: 150–164.
Waines, J.G. (1976). A model for the origin of diploidizing mechanisms in polyploid species. Am. Nat. 110: 415–430.
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Dhaliwal, H.S. The Ph gene and the origin of tetraploid wheats. Genetica 47, 177–182 (1977). https://doi.org/10.1007/BF00123238
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DOI: https://doi.org/10.1007/BF00123238