The epiphytic fern Elaphoglossum luridum (Fée) Christ. (Dryopteridaceae) from Central and South America: morphological and physiological responses to water stress.
Elaphoglossum luridum (Fée) Christ. (Dryopteridaceae) is an epiphytic fern of the Atlantic Forest (Brazil). Anatomical and physiological studies were conducted to understand how this plant responds to water stress. The E. luridum frond is coriaceus and succulent, presenting trichomes, relatively thick cuticle, and sinuous cell walls in both abaxial and adaxial epidermis. Three treatments were analyzed: control, water deficit, and abscisic acid (ABA). Physiological studies were conducted through analysis of relative water content (RWC), photosynthetic pigments, chlorophyll a fluorescence, and malate content. No changes in RWC were observed among treatments; however, significant decreases in chlorophyll a content and photosynthetic parameters, including optimal irradiance (I opt) and maximum electron transport rate (ETRmax), were determined by rapid light curves (RLC). No evidence of crassulacean acid metabolism (CAM) pathway was observed in E. luridum in response to either water deficit or exogenous application of ABA. On the other hand, malate content decreased in the E. luridum frond after ABA treatment, seeming to downregulate malate metabolism at night, possibly through tricarboxylic acid (TCA) cycle regulation.
Department of Botany, Federal University of Santa Catarina, CP 476, 88049-900 Florianópolis, SC, Brazil.
Bruno Degaspari
BD
Minardi
Department of Botany, Federal University of Santa Catarina, CP 476, 88049-900 Florianópolis, SC, Brazil.
Ana Paula Lorenzen
AP
Voytena
Department of Botany, Federal University of Santa Catarina, CP 476, 88049-900 Florianópolis, SC, Brazil.
Marisa
0000-0002-9425-8330
M
Santos
Department of Botany, Federal University of Santa Catarina, CP 476, 88049-900 Florianópolis, SC, Brazil.
Aurea Maria
AM
Randi
D000040:Abscisic Acid / Q000494:pharmacology*; D001938:Brazil; D029624:Ferns / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D065928:Forests; D008027:Light; D013020:South America; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism*
D014867:Water; D000040:Abscisic Acid