How does a C-3 epiphytic tank bromeliad respond to drought?

Autor(es)

Katayama Gobara, Bruno Nobuya ; Rodrigues Alves, Frederico Rocha ; Pikart, Filipe Christian ; Goncalves, Ana Zangirolame ; Alves Cursino Dos Santos, Deborah Yara ; De Albuquerque Melo De Pinna, Gladys Flavia ; Mercier, Helenice

• Tipo de documento: Artigo Científico
• Fonte: Botanical Journal of the Linnean Society; v. 192, n. 4, p. 13-pg., 2020-04-01.

Resumo

Intermittent water availability characterizes the canopy habitat, but few studies have focused on how C-3 epiphytic bromeliads deal with drought. In this context, we investigated how water deficits affect the photosynthetic responses of the epiphytic bromeliad Vriesea gigantea regarding its physiological and anatomical traits that can minimize the effects of stomatal closure. In a controlled experiment in which bromeliads were submitted to 21 days of drought, we demonstrated a reduction in the leaf water content followed by strong reductions in net CO2 exchange and the efficiency of the photochemical system. However, there were increases in the yield of non-photochemical quenching and the activities of hydrophilic antioxidants. We observed substomatal chambers connected with air channels reaching the chlorophyllous parenchyma. Our findings indicate that the low net CO2 exchange and the energy imbalance possibly increased the cyclic transport of electrons and activated the thermal dissipation of energy to avoid damage to the photosynthetic apparatus. Additionally, the aeration channels may passively store CO2 to facilitate its re-assimilation. Because most epiphytic bromeliads are C-3 plants and drought is frequent in the canopy, we speculate that some attributes of V. gigantea may occur in other C-3 species, favouring their radiation in the epiphytic environment. (AU)

• Processo FAPESP: 11/50637-0 - Competência para a expressão do metabolismo ácido das crassuláceas (CAM) em bromélia epífita: sinalização, modulação da expressão, perfil transcricional e interação com o metabolismo de nitrogênio
• Beneficiário: Helenice Mercier
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/09699-5 - Metabolismo do nitrogênio e sua interação com o metabolismo ácido das crassuláceas (CAM) em Guzmania monostachia (Bromeliaceae): uma abordagem fisiológica e molecular
• Beneficiário: Ana Zangirólame Gonçalves
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/22267-9 - Caracterização da capacidade de indução ao CAM em plantas de Vriesea gigantea (Bromeliaceae) sob déficit hídrico
• Beneficiário: Bruno Nobuya Katayama Gobara
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 18/12667-3 - Explorando aspectos fisiológicos e moleculares em Guzmania monostachia (Bromeliaceae): estudo das vias funcionais da fotossíntese e de resposta a nutrientes.
• Beneficiário: Helenice Mercier
• Modalidade de apoio: Auxílio à Pesquisa - Regular