Describing heterostyly, pollen, and sexual organ reciprocity in Rourea chrysomalla (Connaraceae), a rare and threatened species from the Brazilian Cerrado

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da Paz, Joicelene Regina Lima ; dos Santos, Beatriz Ribeiro ; Sa, Tulio Freitas Filgueira ; Faria, Jair Eustaquio Quintino ; Silva, Wagner Pereira ; Toledo, Cassio Augusto Patrocinio ; Pigozzo, Camila Magalhaes ; Bellonzi, Talita Kely ; Gasparino, Eduardo Custodio ; Souza, Vinicius Castro ; Vallejo-Marin, Mario ; Consolaro, Helder Nagai

• Tipo de documento: Artigo Científico
• Fonte: FLORA; v. 314, p. 10-pg., 2024-04-03.

Resumo

Rourea chrysomalla is a rare and endemic plant species from the Brazilian Cerrado, presumably threatened and lacking records within conservation units. In this study, we recorded and characterized, for the first time, the floral and pollen dimorphism, as well as the reciprocity of sexual organs among different morphs of R. chrysomalla. For this purpose, fertile individuals were observed over three years in two natural populations and supplemented by herbarium data. This species is distylous and distinctly exhibits two types of flowers, each characterized by stamens arranged in two whorls of unequal lengths: L-styled and S-styled morphs, both occuring in similar proportions in the two populations. Cross-pollination among anthers of any stamen whorl in L-styled flowers and stigmas in S-styled flowers is more precise in the two morphs, while anthers in S-styled flowers are less reciprocal with the stigmas in L-styled flowers. S-styled flowers exhibit larger pollen grains compared to Lstyled flowers, with no differences between the two whorls of stamens. The balanced proportion of floral morphs provides equal opportunities for pollen donation and reception, and reciprocity between morphs is essential for the conservation of R. chrysomalla due to its limited distribution and low population density in the central Brazilian savanna. (AU)

• Processo FAPESP: 19/03173-0 - Estudos sistemáticos, ontogenéticos, reprodutivos e fitoquímicos em Connaraceae, com ênfase nas espécies neotropicais
• Beneficiário: Vinicius Castro Souza
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 23/00985-9 - Evolução do sistema reprodutivo e implicações para a morfologia floral em Connaraceae, com ênfase nas espécies neotropicais
• Beneficiário: Joicelene Regina Lima da Paz
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 22/03702-5 - Gerenciamento de dados sobre as Connaraceae
• Beneficiário: Joicelene Regina Lima da Paz
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico