Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-17T17:18:41.418Z Has data issue: false hasContentIssue false
  • English
  • Français

Changing Concepts in Crop Plant Evolution*

Published online by Cambridge University Press:  03 October 2008

Sir Joseph Hutchinson
Sir Joseph Hutchinson
Affiliation:
St. John's College, Cambridge
Get access Rights & Permissions [Opens in a new window]

Summary

Evolutionary studies in the cottons began with the demonstration by Harland that true cottons could be divided into four genetically distinct species, each carrying an internally balanced genotype that was disrupted in crosses with any other. Harland's genetic classification has stood the test of time, and contributes substantially to our understanding of speciation in other genera, as for example, Phaseolus. In addition, it provides a genetic basis for the observations described by Anderson as ‘introgression’.

Studies of cottons found growing wild, and of their relationship to cultivars in the same areas, led to the hypothesis that all true cottons are cultivars, and those now found wild are escapes. This hypothesis, though it led to purposeful exploration of the distribution and relationships of the cottons, was found to be inadequate. A new approach to the relationships of the cottons became possible following Thoday's demonstration of ‘disruptive selection’ in Drosophila. The disruptive situation has been shown to obtain as between cultivars and their wild relatives in Sorghum and in a number of other crop plants.

Consideration of the time scale of agricultural evolution makes it clear that the recent origin theory is untenable, and a review of the status of the ‘wild’ cottons shows that they are adequately accounted for as weedy relatives of the cultivars, descended from common wild ancestors under disruptive selection.

It is concluded that crop plant evolution has gone on very largely within the balanced gene pools which Harland regarded as genetic species.

Type
Research Article
Information
Experimental Agriculture , Volume 7 , Issue 4 , October 1971 , pp. 273 - 280
Copyright
Copyright © Cambridge University Press 1971

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

Anderson, E. (1949). Introgressive Hybridisation. New York: John Wiley.CrossRefGoogle Scholar
Bird, J. B. & Mahler, J. (1951-1952). Amer. Fabrics 20, 73.Google Scholar
Chowdhury, K. A. & Buth, G. M. (1970). Nature 227, 85.CrossRefGoogle Scholar
Doggett, H. (1970). Sorghum. London: Longmans.Google Scholar
Engel, F. (1963). Trans. Am. Phil. Soc. N.S., 53.CrossRefGoogle Scholar
Gerstel, D. U. (1953). Evolution 7, 234.CrossRefGoogle Scholar
Gulati, S. M. & Turner, A. J. (1928). Ind. Cent. Cott. Cttee. Tech. Lab. Bull. 17.Google Scholar
Harland, S. C. (1936). Biol. Rev. 11, 82.CrossRefGoogle Scholar
Helbaek, H. (1966). Econ. Bot. 20, 350.CrossRefGoogle Scholar
Hutchinson, J. B. (1959). The Application of Genetics to Cotton Improvement. Cambridge: University Press.Google Scholar
Hutchinson, J. B. (1965). In Hutchinson, J. B. (ed.). Essays on Crop Plant Evolution. Cambridge: University Press.Google Scholar
Hutchinson, J. B., Silow, R. A. & Stephens, S. G. (1947). The Evolution of Gossypium. Oxford: University Press.Google Scholar
Knight, R. L. (1945). J. Genet. 47, 76.CrossRefGoogle Scholar
Knight, R. L. (1949). Sudan Min. Agric, Res. Div. Mem. 19 Khartoum.Google Scholar
MacNeish, R. S. (1964). Science 143, 531.CrossRefGoogle Scholar
Mehta, K. L. (1963). Phyton 20, 189.Google Scholar
Riley, R. (1965). In Hutchinson, J. B. (ed.). Essays on Crop Plant Evolution. Cambridge: University Press.Google Scholar
Sears, E. G. (1959). Handbuch der Pflanzenzuchtung 2, 164.Google Scholar
Thoday, J. M. (1964). Genetics Today 3, 533.Google Scholar
Vishnu-Mittre, (1968). Trans. Bose Res. Inst. 31, 87.Google Scholar