Distyly and variation in floral traits in natural populations of Psychotria ipecacuanha (Brot.) Stokes (Rubiaceae)

Psychotria ipecacuanha is a perennial, medicinal herb that grows in clusters in the understory of humid, shady areas of the Atlantic Rain Forest of southeastern Brazil. The present study characterized the variation in floral traits among 35 clusters from three natural populations of this plant speci...

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Detalhes bibliográficos
Autores: Oliveira, Luiz Orlando de, Vieira, Milene F., Rossi, Ana Aparecida B.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2005
País:Brasil
Recursos:Universidade Federal de Viçosa (UFV)
Repositório:LOCUS Repositório Institucional da UFV
Idioma:inglês
OAI Identifier:oai:locus.ufv.br:123456789/26880
Acesso em linha:http://dx.doi.org/10.1590/S0100-84042005000200009
https://locus.ufv.br//handle/123456789/26880
Access Level:Acceso aberto
Palavra-chave:Distyly
Floral morphology
Ipecac
Medicinal plants
Psychotria ipecacuanha
Distilia
Morfologia floral
Plantas medicinais
Poaia
Descrição
Resumo:Psychotria ipecacuanha is a perennial, medicinal herb that grows in clusters in the understory of humid, shady areas of the Atlantic Rain Forest of southeastern Brazil. The present study characterized the variation in floral traits among 35 clusters from three natural populations of this plant species. Field observations showed that the clusters are isomorphic, that is, a given cluster will either set long-styled or short-styled flowers. Stigmas and anthers are reciprocally placed in each morph, a dimorphism characteristic of distyly. The populations are isoplethic, that is, a given population exhibits an equilibrium 1:1 ratio of floral morphs. Morphometric analyses revealed that anther length, stigma length, corolla diameter, and pollen grain diameter were consistently greater in short-styled flowers, regardless of the population investigated. Significant differences for floral traits in the short-styled morph were found among populations. Floral traits in the long-styled morph also showed some significant differences among populations, but not for stigma height and corolla length. Controlled pollinations carried out in natural populations showed that fruit production was higher after inter-morph pollination. Nevertheless, observations of pollen tube growth in style, and also fruit production after spontaneous self-pollination and intra-morph pollination, indicated partial intramorph compatibility in this plant species.