Consulta: subjectFacets:"Distyly"
Registros recuperados: 4
Data/hora: 13/06/2024 02:12:16

Sistemas reprodutivos e polinização em espécies simpátricas de Erythroxylum P. Br. (Erythroxylaceae) do Brasil
Provedor de dados: 88
Autores: BARROS,MARILUZA GRANJA e.
Foram investigadas a biologia reprodutiva e a polinização de Erythroxylum campestre St. Hil., E. suberosum St. Hil. e E. tortuosum Mart., ocorrentes na Fazenda Água Limpa, Brasília, DF. Estas espécies são simpátricas, comumente encontradas em cerrados abertos e florescem em média quatro meses por ano. As três espécies são distílicas, isto é, apresentam flores com estiletes longos (longistiladas) e flores com estiletes curtos (brevistiladas), ambas com estames em posicionamentos correspondentes. As flores são similares, pequenas, suavemente perfumadas, de cor creme claro, diurnas, produtoras de néctar (concentração média de sacarose de 20,2%) e duram um dia. Os testes de polinização artificial revelaram que E. suberosum e E. tortuosum são auto-incompatíveis...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Erythroxylum; Sympatry; Distyly; Incompatibility.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84041998000200008

Distyly and variation in floral traits in natural populations of Psychotria ipecacuanha (Brot.) Stokes (Rubiaceae)
Provedor de dados: 88
Autores: Rossi,Ana Aparecida B.; Oliveira,Luiz Orlando de; Vieira,Milene F.
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...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Distyly; Floral morphology; Ipecac; Medicinal plants; Psychotria ipecacuanha.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042005000200009

Floral biology and breeding system of Psychotria tenuinervis Muell. Arg. (Rubiaceae) in the Atlantic rain forest, SE Brazil
Provedor de dados: 39
Autores: Virillo,Carolina Bernucci; Ramos,Flavio Nunes; Castro,Cibele Cardoso de; Semir,João.
(Floral biology and breeding system oi Psychotria tenuinervis Muell. Arg. (Rubiaceae) in the Atlantic rain forest, SE Brazil). The aim of this study was to investigate pollination biology, floral morphometry, morph ratio and breeding system oiPsychotria tenuinervis in an area of Atlantic rain forest in southeastern Brazil. Pollination biology was studied based on focal observations and the breeding system was determined using controlled crosses; data on flower production and floral morphometry were compared between the two floral morphs. Flower production by the two floral morphs was similar, with flowers being reciprocally herkogamous, diurnal and pollinated at similar frequencies, mainly by medium-sized bees. Corolla length and diameter, as well as...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Atlantic forest; Distyly; Flower; Herkogamy; Pollination.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062007000400012

Risk of genetic vulnerability and aspects of the reproductive biology of Psychotria ipecacuanha (Rubiaceae), a threatened medicinal plant species of Brazilian forests
Provedor de dados: 39
Autores: Silva,Patrícia Campos da; Nascimento,Talita Oliveira; Krause,Willian; Chaves,Douglas Siqueira de Almeida; Silva,Celice Alexandre.
ABSTRACT Psychotria ipecacuanha, commonly known as Ipeca, is a medicinal plant of pharmacological and economic value. The species is distylous; it has populations with two floral morphs, one with long and one with short styles. Apart from the presence of two floral morphs in a balanced ratio (1:1), reciprocal herkogamy of the reproductive organs between alternative morphs is desirable to maintain cross-pollination. The risk factors for genetic erosion and conditions for sexual reproduction in natural populations of P. ipecacuanha were investigated. The main risks for genetic erosion in four populations studied were: habitat change in the forest fragment where they occurred and in the surrounding area over the last 20 years; proximity to agricultural areas;...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Distyly; Floral morphs; Genetic erosion; Ipeca; Reciprocal herkogamy.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062019000300548