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Evidence for interspecific hybridisation in pteridophytes with subterranean mycoparasitic gametophytes

Published online by Cambridge University Press:  05 December 2011

W. H. Wagner Jr
Affiliation:
The University of Michigan, Ann Arbor, Michigan, U.S.A.
F. S. Wagner
Affiliation:
The University of Michigan, Ann Arbor, Michigan, U.S.A.
Joseph M. Beitel
Affiliation:
Sarah Lawrence College, Bronxville, New York, U.S.A.
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Synopsis

Pteridophytes with subterranean sexual stages exist in five families. Their prothalli grow underground without light, nourished by fungi, and are rounded, massive, and without chlorophyll. Various authors have suggested that such gametophytes may inhibit outbreeding ability and that minor variations may therefore form in colonies through inbreeding.

This paper questions these ideas. The subterranean condition is believed to be suited to fields, grassy meadows, and other habitats subject to seasonal drying. The parenchymatous thallus makes possible water storage. Water can flow between some particles. Sperm may be carried by mass flow in various directions and can evidently swim as much as 2 cm. Close clumping of underground gametophytes appears to be no less common than in surficial gametophytes and evidence exists that hybridisation occurs.

No evidence has been detected that outbreeding is inhibited, and we conclude that it is successful and that cross-fertilisation is no less common among underground gametophytes than among surface gametophytes. Numerous examples are listed from Lycopodiales, Psilotales, and Ophioglossales.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1985

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References

Beitel, J. M. 1979a. The clubmosses Lycopodium sitchense and L. sabinifolium in the upper Great Lakes Region. Mich. Bot. 18, 313.Google Scholar
Beitel, J. M. 1979b. Clubmosses (Lycopodium) in North America. Fiddlehead Forum. Bull. Am. Fern Soc. 6 (5), 18.Google Scholar
Beitel, J. M. 1979c. The effects of sun and shade on Lycopodium sitchense and L. sabinifolium with respect to their taxonomic status. Misc. Publs Bot. Soc. Am. 157, 46.Google Scholar
Beitel, J. M. 1979d. Lycopodium. In Endangered and Threatened Plants and Animals of Virginia, ed. Linzey, D. W., pp. 5659. Blacksburg, Virginia: Va. Polytech. Institute and State University.Google Scholar
Beitel, J. M., Hansen, M. K. and Walter, K. S. 1982. The effect of sun and shade on Lycopodium × habereri (digitatum × tristachyum). Misc. Publs Bot. Soc. Am. 162, 7475.Google Scholar
Bierhorst, D. W. 1971. Morphology of Vascular Plants. New York: Macmillan.Google Scholar
Bruce, J. G. and Beitel, J. M. 1979. A community of Lycopodium gametophytes in Michigan. Am. Fern J. 69, 3341.CrossRefGoogle Scholar
Damboldt, J. 1963. Zur Kenntnis der flachen Barläppe in Bayern. Ber. Bayer Bot. Ges. 36, 2527.Google Scholar
Foster, D. B. 1964. The gametophytes and embryogeny of five species of Botrychium. Doctoral thesis, Cornell University, Ithaca, New York.Google Scholar
Hersey, R. E. and Britton, D. M. 1981. A cytological study of three species and a hybrid taxon of Lycopodium (Section Complanata) in Ontario. Can. J. Genet. Cytol. 23, 497504.CrossRefGoogle Scholar
Holub, J. 1975a. Diphasiastrum, a new genus in Lycopodiaceae. Preslia 47, 97110.Google Scholar
Holub, J. 1975b. Notes on some species of Diphasiastrum. Preslia 47, 232240.Google Scholar
Jermy, A. C. and Walker, T. G. 1977. A note on the cytology of Botrychium lanuginosum and the occurrence of the genus in Malesia. Gdns' Bull. Singapore 30, 293298.Google Scholar
Sahashi, N. 1982. Morphological and taxonomic studies on Ophioglossales in Japan and the adjacent regions. Doctoral thesis, Toho University, Chiba, Japan.Google Scholar
Spessard, E. A. 1917. Prothallia of Lycopodium in America. Bot. Gaz. 63, 6676.CrossRefGoogle Scholar
Spessard, E. A. 1922. Prothallia of Lycopodium in America. II L. lucidulum and L. obscurum var. dendroideum. Bot. Gaz. 74, 392413.CrossRefGoogle Scholar
Wagner, F. S. 1980. Chromosome behavior in three interspecific hybrids of Diphasiastrum (Lycopodiaceae). Misc. Publs Bot. Soc. Am. 158, 121122.Google Scholar
Wagner, W. H. Jr., 1968. Hybridization, taxonomy, and evolution. In Modem Methods of Plant Taxonomy, ed. Heywood, V. H., pp. 113138. London and New York: Academic Press.Google Scholar
Wagner, W. H. Jr., 1980. A probable new hybrid grapefern, Botrychium matricariifolium × simplex from Central Michigan. Mich. Bot. 19, 3136.Google Scholar
Wagner, W. H. Jr., 1983. Reticulistics: The recognition of hybrids and their role in cladistics and classification. In Advances in Cladistics, Vol. 2, ed. Platnick, N. L. and Funk, V. A., pp. 6379. New York: Columbia University Press.Google Scholar
Wagner, W. H. Jr. and Wagner, F. S. 1981. New species of moonworts, Botrychium subg. Botrychium (Ophioglossaceae) from North America. Am. Fern J. 71, 2030.CrossRefGoogle Scholar
Wagner, W. H. Jr. and Wagner, F. S. 1982. Genus communities as a systematic tool in the study of New World Botrychium. Taxon 32, 5163.CrossRefGoogle Scholar
Wagner, W. H. Jr. and Wagner, F. S. and Haufler, C. 1982. A hybrid population involving the ‘all-fertile’ B. paradoxum and the hemidimorphic B. hesperium. Misc. Publs Bot. Soc. Am. 162, 7778.Google Scholar
Wilce, J. H. 1965. Sect. Complanata of the genus Lycopodium. Beih. Nova Hedwigia 19, 1233.Google Scholar
Whittier, D. P. 1976. Tracheids, apogamous leaves, and sporophytes in gametophytes of Botrychium dissectum. Bot. Gaz. 127, 237241.CrossRefGoogle Scholar