Drought-induced lacuna formation in the stem causes hydraulic conductance to decline before xylem embolism in Selaginella

Bibliographische Detailangaben
Veröffentlicht in:	The New phytologist. - 1979. - 227(2020), 6 vom: 01. Sept., Seite 1804-1817
1. Verfasser:	Cardoso, Amanda A (VerfasserIn)
Weitere Verfasser:	Visel, Dominik, Kane, Cade N, Batz, Timothy A, García Sánchez, Clara, Kaack, Lucian, Lamarque, Laurent J, Wagner, Yael, King, Andrew, Torres-Ruiz, José M, Corso, Déborah, Burlett, Régis, Badel, Eric, Cochard, Hervé, Delzon, Sylvain, Jansen, Steven, McAdam, Scott A M
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2020
Zugriff auf das übergeordnete Werk:	The New phytologist
Schlagworte:	Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. ABA embolism evolution hydraulic conductance lycophyte stomatal conductance mehr... stomatal evolution Water 059QF0KO0R

Beschreibung
Zusammenfassung:	© 2020 The Authors. New Phytologist © 2020 New Phytologist Trust. Lycophytes are the earliest diverging extant lineage of vascular plants, sister to all other vascular plants. Given that most species are adapted to ever-wet environments, it has been hypothesized that lycophytes, and by extension the common ancestor of all vascular plants, have few adaptations to drought. We investigated the responses to drought of key fitness-related traits such as stomatal regulation, shoot hydraulic conductance (Kshoot ) and stem xylem embolism resistance in Selaginella haematodes and S. pulcherrima, both native to tropical understory. During drought stomata in both species were found to close before declines in Kshoot , with a 50% loss of Kshoot occurring at -1.7 and -2.5 MPa in S. haematodes and S. pulcherrima, respectively. Direct observational methods revealed that the xylem of both species was resistant to embolism formation, with 50% of embolized xylem area occurring at -3.0 and -4.6 MPa in S. haematodes and S. pulcherrima, respectively. X-ray microcomputed tomography images of stems revealed that the decline in Kshoot occurred with the formation of an air-filled lacuna, disconnecting the central vascular cylinder from the cortex. We propose that embolism-resistant xylem and large capacitance, provided by collapsing inner cortical cells, is essential for Selaginella survival during water deficit
Beschreibung:	Date Completed 14.05.2021 Date Revised 14.05.2021 published: Print-Electronic Citation Status MEDLINE
ISSN:	1469-8137
DOI:	10.1111/nph.16649