Subgroups in theHordeum patagonicum complex (Poaceae)
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Abstract
Seeds of theHordeum patagonicum complex were collected from the field and grown in the greenhouse. The aim was to take a sample of members of the complex, and on the basis of the phenotypic similarities in some morphological and physiological characters, determine whether distinct groups exist. When cluster analyses, to generate hypotheses, and orthodox statistical procedures, for hypotheses obtained a priori, were applied to the reproductive morphology, germination and flowering patterns, onlyH. patagonicum subsp.magellanicum, out of the five recognized taxa, could be distinguished consistently. The remaining four taxa, which overlapped considerably, could be re-formed into three groups whose centroids were different but whose ranges of variation were not distinct from each other. We conclude that the highly cross-compatible members of theH. patagonicum complex, first defined as species and later redefined as subspecies are probably no more than biotypes.
Key words
Angiosperms Poaceae Hordeum patagonicum complex barley Classification numerical methods evolutionPreview
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References
- Bothmer, R. von, Jacobsen, N., 1979: Biosystematic investigations in the genusHordeum. — Proc. Conf. Broadening Genet. Base Crops, 60Wageningen, 1978. — Wageningen: Pudoc.Google Scholar
- Bothmer, R. von, Giles, B. E., Jacobsen, N., 1986: Crosses and genome relationship in theHordeum patagonicum group. — Genetica71: 75–80.Google Scholar
- —, 1988: Taxonomy and variation in theHordeum patagonicum group. — Bot. Jahrb. Syst.109: 373–384.Google Scholar
- Bradshaw, A. D., 1972: Some of the evolutionary consequences of being a plant. — Evol. Biol.5: 25–47.Google Scholar
- Gower, J. C., 1966: Some distance properties of latent root and vector methods used in multivariate analysis. — Biometrica53: 523–338.Google Scholar
- —, 1971: A general coefficient of similarity and some of its properties. — Biometrics27: 857–871.Google Scholar
- Lefkovitch, L. P., 1976: Hierarchical clustering from principal coordinates: an efficient method for small to very large numbers of objects. — Math. Biosci.31: 157–174.Google Scholar
- —, 1982: Conditional clusters, musters, and probability. — Math. Biosci.60: 207–234.Google Scholar
- —, 1984: A nonparametric method for comparing dissimilarity matrices, a general measure of biogeographical distance, and their application. — Amer. Naturalist123: 484–499.Google Scholar
- —, 1985: Further nonparametric tests for comparing dissimilarity matrices based on the relative neighborhood graph. — Math. Biosci.73: 71–88.Google Scholar
- —, 1987: Clustering from ordination. — Math. Biosci.87: 17–30.Google Scholar
- Levin, D. A., 1979: The nature of plant species. — Science204: 381–384.Google Scholar
- Madsen, K., Nielsen, E. S., Ødum, S., 1980: The Danish scientific expedition to Patagonia and Tierra del Fuego 1978–1979. — Geografisk Tidsskrift80: 1–28.Google Scholar
- McCullagh, P., Nelder, J. A., 1983: Generalized linear models. — London: Chapman & Hall.Google Scholar
- Nicora, E., 1978:Gramineae. — InCorrea, M. N., (Ed.): Flora Patagonia,7, 3, pp. 1–580. — Buenos Aires: INTA.Google Scholar
- Prentice, H. C., 1986: Continuous variation and classification. — InStyles, B. T., (Ed.): Infraspecific classification of wild and cultivated plants. The Systematics Association Special Volume29. — Oxford: Clarendon Press.Google Scholar