Agricultural and Biological Sciences, Ecology, Evolution, Behavior and Systematics, Plant Science
28
Scopus Publications
Scopus Publications
Floral anatomy of Bromeliaceae species occurring in the coastal restinga of Florianópolis, Santa Catarina State, Brazil Sacha Arielle Branco, Raoni Lorizolla Cordeiro, Ana Claudia Rodrigues, Fernanda Maria Cordeiro de Oliveira Hoehnea, 2026 A família Bromeliaceae Juss., predominante nos Neotrópicos, apresenta flores trímeras e pentacíclicas, destacandose pela presença de nectários septais. Esses nectários, junto às demais estruturas secretoras florais, têm relevância para a reprodução, atração de polinizadores e proteção floral. Este estudo visou caracterizar a anatomia floral e a histoquímica de Aechmea comata, Dyckia encholirioides e Vriesea friburgensis. Flores em pré-antese foram coletadas, fixadas em FAA 50 e FNT, e submetidas a técnicas usuais de anatomia vegetal. Cortes histológicos foram corados com Astra Azul e Safranina, enquanto testes histoquímicos detectaram compostos como proteínas (Xylidine Ponceau), polissacarídeos (PAS) e lipídios (Sudan IV). O tecido transmissor foi identificado no estigma e estilete, com secreções ricas em proteínas, mucilagem e lipídios. Nectários septais (A. comata) e infraloculares (D. encholirioides e V. friburgensis) apresentaram secreções similares. Canais secretores nas sépalas de V. friburgensis cujo conteúdo é composto por mucilagem e proteínas foram descritos. O estudo contribui para o conhecimento anatômico e funcional das flores em Bromeliaceae, reforçando sua importância ecológica e filogenética. Os achados destacam o papel dos tecidos secretores na interação com polinizadores e na proteção floral, abrindo caminho para investigações futuras sobre sua relevância evolutiva.
Plastid role in phytomelanin synthesis in Piptocarpha axillaris (Less.) Baker stems (Asteraceae, Vernonieae) Josiane Wolff Coutinho, Ana C. Rodrigues, Beatriz Appezzato-da-Glória, Eliana M. Oliveira, Fernanda M. C. Oliveira, et al. Protoplasma, 2021 Phytomelanin is a brown to black pigment found in plant tissues, mainly in Asparagales and Asteraceae species. However, few studies deal with the processes of its synthesis, and there are still many questions to be answered regarding the organelles involved in this process and their functions, especially in vegetative organs. In a previous study with stems and leaves of 77 Vernonieae (Asteraceae) species, phytomelanin was demonstrated to always be associated with sclereids, which suggests the involvement of these cells in the pigment synthesis. Thus, we selected another species of tribe Vernonieae, Piptocarpha axillaris (Less.) Baker, which produces abundant phytomelanin secretion in stem tissues, to investigate which cells and organelles are involved in the synthesis and release of this pigment, as well as its distribution in the tissues. To achieve this goal, stems in different developmental phases were analyzed under light and transmission electron microscopy. Anatomical analysis showed that the polymerization of phytomelanin in P. axillaris starts at the second stem node, in the pith region, and occurs simultaneously with sclereid differentiation. The plastids of cells that will differentiate into sclereids actively participate in the phenolic material synthesis, following the "tannosome" and the "pearl necklace" models, giving rise to the main precursor of phytomelanin, which is then polymerized in the intercellular spaces during the sclerification process of sclereids. In stems with an established secondary structure, the pigment can be observed more frequently in the cortex, pericycle, primary phloem, secondary phloem, and pith.
Androecium and gynoecium anatomy of Bromeliaceae species Fernanda Maria Cordeiro de Oliveira, Ana Claudia Rodrigues, Makeli Garibotti Lusa, Gladys Flavia de Albuquerque Melo-de-Pinna Flora Morphology Distribution Functional Ecology of Plants, 2020
