Display options
Cite
Dhaliwal HS, Johnson BL. Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor. Theor Appl Genet. 1982;61(2):117-23doi: 10.1007/BF00273878.
Dhaliwal, H. S., & Johnson, B. L. (1982). Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor. TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik, 61(2), 117-23. https://doi.org/10.1007/BF00273878
Dhaliwal, H S, and Johnson, B L. "Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor." TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik vol. 61,2 (1982): 117-23. doi: https://doi.org/10.1007/BF00273878
Dhaliwal HS, Johnson BL. Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor. Theor Appl Genet. 1982 Jun;61(2):117-23. doi: 10.1007/BF00273878. PMID: 24270332.
Copy Download .nbib Format: NLM
Share it on

Theor Appl Genet. 1982 Jun;61(2):117-23. doi: 10.1007/BF00273878.

Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor.

TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik

H S Dhaliwal, B L Johnson

Affiliations

  1. Regional Research Station, Punjab Agricultural University, Gurdaspur, India.

PMID: 24270332 DOI: 10.1007/BF00273878

Abstract

The genomes of the diploid wheats Triticum boeoticum and T. urartu are closely related, giving 7II in the f1 hybrid (T(b)T(u)) and 8.4 (0-14) II + 2.5 (0-7) IV in the derived amphiploid (T(b)T(b)T(u)T(u)). The genomes of the tetraploid wheats are also closely related, giving up to 7II at the polyhaploid level (AB) in the absence of the gene Ph but 14II at the tetraploid level (AABB) in the normal presence of Ph. If the amphiploid is the progenitor of the tetraploids, one or the other homoeologue (T(b) or T(u)) in each of the 7 homoeologous groups (the 7 potential IV) must have differentiated with respect to pairing affinity in order to account for 14II in the tetraploid. Consequently, in tetraploid X amphiploid hybrids (T(b)T(u)AB) carrying the Ph gene from the tetraploid, the seven differentiated chromosomes (B) would be expected to give 7I while, on the basis of their observed chiasma frequency, T(b), T(u) and the less differentiated A would be expected to give 4.17I + 3.57II + 3.23III), assuming homoeologous pairing. The expected chromosomal configuration freqencies at MI (11.17I + 3.57II + 3.23III) closely fit the observed values (11.22I + 3.45II + 3.19III + 0.071IV) for such hybrids (X(2) = 0.0046; P>0.99). Thus diploidization of the boeoticum-urartu amphiploid clearly could account for the origin of the tetraploid wheats. Furthermore, T. aestivum X amphiploid hybrids (T(b)T(u)ABD) with and without Ph indicated that B as well as A chomosomes tended to pair with their presumed T(b)T(u) homologues in the absence of Ph. Other tests showed that the tetraploid wheats could not plausibly have originated from any postulated Triticum-Sitopsis (TTSS) parental combinations with or without such chromosomal differentiation.

References

  1. Genetics. 1979 Apr;91(4):755-67 - PubMed
  2. J Hered. 1946 Mar;37:81 107 - PubMed
  3. Proc Natl Acad Sci U S A. 1972 Jun;69(6):1398-402 - PubMed
  4. Annu Rev Genet. 1976;10:31-51 - PubMed

Publication Types