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

Author(s)

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

• Document type: Journal article
• Source: Botanical Journal of the Linnean Society; v. 192, n. 4, p. 13-pg., 2020-04-01.

Abstract

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)

• FAPESP's process: 11/50637-0 - Competence for Crassulacean Acid Metabolism (CAM) expression in epiphytic bromeliad: signaling, modulation of expression, transcriptional profile and interaction with the nitrogen metabolism
• Grantee: Helenice Mercier
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/09699-5 - Nitrogen metabolism and its interaction with the Crassulacean acid metabolism (CAM) in Guzmania monostachia (Bromeliaceae): a physiological and molecular approach
• Grantee: Ana Zangirólame Gonçalves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/22267-9 - Characterization of the capacity to induce CAM in plants of Vriesea gigantea (Bromeliaceae) under water deficit
• Grantee: Bruno Nobuya Katayama Gobara
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 18/12667-3 - Exploring the physiological and molecular aspects of Guzmania monostachia (Bromeliaceae): studying the functional pathways of photosynthesis and nutrient responses.
• Grantee: Helenice Mercier
• Support Opportunities: Regular Research Grants