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Selection for growth-rate during asexual and sexual propagation in Phytophthora cactorum

Published online by Cambridge University Press:  14 April 2009

Donald MacIntyre  and
Charles G. Elliott
Donald MacIntyre
Affiliation:
Botany Department, University of Glasgow
Charles G. Elliott
Affiliation:
Botany Department, University of Glasgow
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Selection for high and low growth-rate was carried out during eight generations of asexual propagation by zoospores and seven generations of sexual reproduction by oospores. The fungus has previously been shown to be diploid during its vegetative phase. In the zoospore lines there was no significant variation and no response to selection, except for the occasional appearance of fast-growing sectors. A high line was established from such a sector; in its sexual progeny the inheritance of growth-rate was non-Mendelian. Propagation through self-fertilized oospores released very considerable genetic variation, and both high and low lines responded to selection. At first the variation within families, and the response to selection, increased with succeeding generations, despite the intense inbreeding. In later generations the high line became less variable, and the progeny oospore cultures resembled the fast-growing sectors. It is concluded that growth-rate is controlled by a polygenic system and by cytoplasmic determinants, a mutant form of which is responsible for the fast-sectoring phenotype.

Type
Research Article
Information
Genetics Research , Volume 24 , Issue 3 , December 1974 , pp. 295 - 309
Copyright
Copyright © Cambridge University Press 1974

References

REFERENCES

Arlett, C. F., Grindle, M. & Jinks, J. L. (1962). The ‘red’ cytoplasmic variant of Aspergillus nidulans. Heredity 17, 197–209.CrossRefGoogle ScholarPubMed
Blackwell, E. (1943). The life history of Phytophthora cactorum (Lab. & Cohn) Schroet. Transactions of the British Mycological Society 26, 71–89.CrossRefGoogle Scholar
Boccas, B. (1972). Contribution à léd;tude du cycle chez les Phytophthora. Analyse du mode de transmission d'un charactère génétique quantitatif chez une espèce homothallique, le Phytophthora syringae Kleb. Comptes Bendus des Séances de l'Académie des Sciences, Paris, D 275, 663–666.Google Scholar
Caten, C. E. (1970). Spontaneous variability of single isolates of Phytophthora infestans. II. Pathogenic variation. Canadian Journal of Botany 48, 897–905.CrossRefGoogle Scholar
Caten, C. E. (1971). Single zoospore variation in Phytophthora infestans and attenuation of strains in culture. Transactions of the British Mycological Society 56, 1–7.CrossRefGoogle Scholar
Caten, C. E. & Jinks, J. L. (1968). Spontaneous variability of single isolates of Phytophthora infestans. I. Cultural variation. Canadian Journal of Botany 46, 329–348.CrossRefGoogle Scholar
Clayton, G. A., Morris, J. A. & Robertson, A. (1957). An experimental check on quantitative genetic theory. I. Short-term responses to selection. Journal of Genetics 55, 131–151.CrossRefGoogle Scholar
Connolly, V. & Simchen, G. (1968). Linkage to the incompatibility factors and maintenance of genetic variation in selection lines of Schizophyllum commune. Heredity 23, 387–402.CrossRefGoogle Scholar
Elliott, C. G. (1968). Competition and synergism between cholesterol and cholestanol in oospore formation in Phytophthora cactorum. Journal of General Microbiology 51, 137–143.CrossRefGoogle ScholarPubMed
Elliott, C. G. & MacIntyre, D. (1973). Genetical evidence on the life-history of Phytophthora. Transactions of the British Mycological Society 60, 311–316.CrossRefGoogle Scholar
Falconer, D. S. (1960). Introduction to Quantitive Genetics. Oliver & Boyd, Edinburgh.Google Scholar
Käfer, E. (1960). High frequency of spontaneous and induced somatic segregation in Aspergillus nidulans. Nature 186, 619–620.CrossRefGoogle Scholar
Mather, K. & Harrison, B. J. (1949). The manifold effect of selection. Heredity 3, 1–52, 131–162.CrossRefGoogle ScholarPubMed
Nga, B. H. & Roper, J. A. (1969). A system generating spontaneous intrachromosome changes at mitosis in Aspergillus nidulans. Genetical Research 14, 63–70.CrossRefGoogle ScholarPubMed
Papa, K. E. (1971). Continuous selection for increased linear growth rate in Neurospora crassa. Journal of Heredity 62, 87–89.CrossRefGoogle ScholarPubMed
Pateman, J. A. (1959). The effect of selection on ascospore size in Neurospora crassa. Heredity 13, 1–21.CrossRefGoogle Scholar
Sansome, E. (1961). Meiosis in the oogonium and antheridium of Pythium debaryanum Hesse. Nature 191, 827–828.CrossRefGoogle Scholar
Sansome, E. (1965). Meiosis in diploid and polyploid sex organs of Phytophthora and Achlya. Cytologia (Tokyo) 30, 103–117.CrossRefGoogle Scholar
Sansome, E. & Brasier, C. M. (1973). Diploidy and chromosomal structural hybridity in Phytophthora infestans. Nature 241, 344–345.CrossRefGoogle Scholar
Shaw, D. S. & Elliott, C. G. (1968). Streptomycin resistance and morphological variation in Phytophthora cactorum. Journal of General Microbiology 51, 71–84.CrossRefGoogle ScholarPubMed
Sismantdis, A. (1942). Selection for an almost invariable character in Drosophila. Journal of Genetics 44, 204–215.CrossRefGoogle Scholar