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Phenetic relationships among populations of the autogamous plant Relbunium hypocarpium (Rubiaceae)

Suzana Cavalli-Molina; Helga Winge

^{Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Caixa Postal 1953, 90001, Porto Alegre, RS, Brasil. Send correspondence to S.C.-M.}

ABSTRACT

Five natural populations of the autogamous plant Relbunium hypocarpium were analyzed for 4 enzyme systems: EST, ACP, GOT and PER. The intra- and interpopulational degree of similarity among the plants was established by Pearson's product-moment correlation coefficients, using the electromorphs as binary characters, the phenograms being obtained by the unweighted pair-group method using arithmetic averages (UPGMA). The theoretical prediction that different self-fertilizing populations are very different in genetic constitution was not confirmed for this species. In the joint results based on the 4 enzyme systems analyzed, the populations of R. hypocarpium presented high genotypical similarity, both at the intra- and interpopulational level although they are geographically very distant. The population with highest genotypic divergence was also that with distinct morphological characteristics, possibly belonging to a distinct subspecies.

Keywords: phenetic; relationships; autogamous; plant; Relbunium hypocarpium.

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