Chemical inhibition of xylem cellular activity impedes the removal of drought-induced embolisms in poplar stems - new insights from micro-CT analysis.

Autor: Secchi F; Department of Agricultural, Forest and Food Sciences, University of Turin, Largo Paolo Braccini 2, Grugliasco, 10095, Italy., Pagliarani C; Institute for Sustainable Plant Protection, National Research Council, Strada delle Cacce 73, Torino, 10135, Italy., Cavalletto S; Department of Agricultural, Forest and Food Sciences, University of Turin, Largo Paolo Braccini 2, Grugliasco, 10095, Italy., Petruzzellis F; Dipartimento di Scienze della Vita, University of Trieste, via Giorgieri 10, Trieste, 34127, Italy., Tonel G; Department of Agricultural, Forest and Food Sciences, University of Turin, Largo Paolo Braccini 2, Grugliasco, 10095, Italy., Savi T; Institute of Botany, Department of Integrative Biology and Biodiversity Research, BOKU, Gregor-Mendel-Straße 33, Vienna, 1180, Austria., Tromba G; Elettra-Sincrotrone Trieste, Area Science Park, Basovizza, Trieste, 34149, Italy., Obertino MM; Department of Agricultural, Forest and Food Sciences, University of Turin, Largo Paolo Braccini 2, Grugliasco, 10095, Italy., Lovisolo C; Department of Agricultural, Forest and Food Sciences, University of Turin, Largo Paolo Braccini 2, Grugliasco, 10095, Italy., Nardini A; Dipartimento di Scienze della Vita, University of Trieste, via Giorgieri 10, Trieste, 34127, Italy., Zwieniecki MA; Department of Plant Sciences, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA.
Jazyk: angličtina
Zdroj: The New phytologist [New Phytol] 2021 Jan; Vol. 229 (2), pp. 820-830. Date of Electronic Publication: 2020 Sep 29.
DOI: 10.1111/nph.16912
Abstrakt: In drought-stressed plants a coordinated cascade of chemical and transcriptional adjustments occurs at the same time as embolism formation. While these processes do not affect embolism formation during stress, they may prime stems for recovery during rehydration by modifying apoplast pH and increasing sugar concentration in the xylem sap. Here we show that in vivo treatments modifying apoplastic pH (stem infiltration with a pH buffer) or reducing stem metabolic activity (infiltration with sodium vanadate and sodium cyanide; plant exposure to carbon monoxide) can reduce sugar accumulation, thus disrupting or delaying the recovery process. Application of the vanadate treatment (NaVO 3, an inhibitor of many ATPases) completely halted recovery from drought-induced embolism for up to 24 h after re-irrigation, while partial recovery was observed in vivo in control plants using X-ray microcomputed tomography. Our results suggest that stem hydraulic recovery in poplar is a biological, energy-dependent process that coincides with accumulation of sugars in the apoplast during stress. Recovery and damage are spatially coordinated, with embolism formation occurring from the inside out and refilling from the outside in. The outside-in pattern highlights the importance of xylem proximity to the sugars within the phloem to the embolism recovery process.
(© 2020 The Authors New Phytologist © 2020 New Phytologist Trust.)
Databáze: MEDLINE
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