Abstract
Allozyme variation between and within eight populations of the diploid annualBidens discoidea was investigated using gel electrophoresis. The species is relatively homogeneous morphologically in comparison with related species and is highly autogamous. Low levels of within-population variation occur at 16 gene loci, and single alleles are nearly fixed at each of seven loci polymorphic for the species. High levels of differentiation occur between populations, with a mean genetic identity of 0.865. The alleles at the polymorphic loci occur in different combinations in the populations with little apparent geographical pattern. Each population is probably composed of a single lineage of highly homozygous individuals with very limited gene flow between populations.
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Roberts, M.L. Allozyme variation in Bidens discoidea (Compositae). Brittonia 35, 239–247 (1983). https://doi.org/10.2307/2806023
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DOI: https://doi.org/10.2307/2806023