Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-06T02:16:38.039Z Has data issue: false hasContentIssue false

The occurrence of hybrid semi-lethals and the cytology of Triticum macha and Triticum vavilovi

Published online by Cambridge University Press:  27 March 2009

Leo Sachs
Affiliation:
Plant Breeding Institute, School of Agriculture, Cambridge

Extract

1. A semi-lethal gene combination has been found in hexaploid species hybrids involving some strains of Triticum macha, but not in comparable hybrids involving other strains of T. macha. The production of these semi-lethal hybrids can be explained by the interaction of two genes designated as ma and mb.

2. The gene ma is carried in some strains of T. macha. The gene mb is carried in the third chromosome set of all other hexaploid species of Triticum, in Aegilops squarrosa and in Aeg. cylindrica.

3. The semi-lethal gene combination has been found between species which would otherwise produce fertile hybrids and between species which would otherwise produce sterile hybrids. The semilethal gene combination occurs between species which do not overlap geographically.

4. The distribution of the genes ma and mb shows that the gene ma originated in T. macha and that the gene mb originated in Aeg. squarrosa and was introduced from there, during the course of evolution, into the hexaploid species of Triticum (probably excluding T. macha) and into Aeg. cylindrica.

5. Meiosis in semi-lethal plants was comparable to meiosis in normal plants. But the semi-lethal plants showed a reduction in fertility, probably as a result of their poor vegetative growth.

6. The chromosomes of T. macha and T. vavilovi have been no more structurally differentiated than the chromosomes of the other hexaploid species of Triticum.

7. The present study has confirmed that the third chromosome set of the genus Triticum has been phylogenetically derived from Aeg. squarrosa.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1953

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bell, G. D. H. & Sachs, Leo (1953). J. Agric. Sci. 43, 105.CrossRefGoogle Scholar
Chin, T. C. & Chwang, C. S. (1944). Bull. Torrey Bot. Cl. 71, 356.CrossRefGoogle Scholar
Dekaprelevich, L. A. & Menabde, V. L. (1932). Bull. Appl. Bot. Genet. Pl. Breed., Ser. 5, no. 1, p. 1.Google Scholar
Dobzhansky, T. (1941). Genetics and the Origin of Species, 2nd ed.New York.Google Scholar
Eig, A. (1929). Rep. Spec. Nov. Reg. Vegt., Beiheft B, 55, 1.Google Scholar
Ellerton, S. (1939). J. Genet. 38, 307.CrossRefGoogle Scholar
Flaksberger, C. A. (1935). Flora of Cultivated Plants. Vol. 1. Wheat. Moscow.Google Scholar
Hutchinson, J. B. (1932). J. Genet. 25, 281.CrossRefGoogle Scholar
Kihara, H. (1949). Cytologia, Tokyo, 14, 135.CrossRefGoogle Scholar
Kihara, H. & Lilienfeld, F. (1949). Proc. 8th Int. Genet. Congr. (Stockholm), p. 307.Google Scholar
Kihara, H., Okamoto, M., Ikegami, M., Tabushi, J., Suemoto, H. & Yamane, Y. (1950). Seiken Ziho, 4, 127.Google Scholar
Love, R. M. (1941). Canad. J. Res. C, 19, 351.CrossRefGoogle Scholar
MacFadden, E. S. & Sears, E. R. (1946). J. Hered. 37, 81, 107.CrossRefGoogle Scholar
Mather, K. (1943). Biol. Rev. 18, 32.CrossRefGoogle Scholar
Sears, E. R. (1944). Genetics, 29, 113.CrossRefGoogle Scholar
Stebbins, G. L. Jr. (1950). Variation and Evolution in Plants. New York.CrossRefGoogle Scholar
Stephens, S. G. (1946). J. Genet. 47, 150.CrossRefGoogle Scholar
Stephens, S. G. (1950). J. Genet. 50, 9.CrossRefGoogle Scholar
Zhukovsky, P. M. (1928). Bull. Appl. Bot. Genet. Pl. Breed. 18, no. 1, 417.Google Scholar