Seasonal and long-term consequences of esca grapevine disease on stem xylem integrity. (15th March 2021)

• Record Type: Journal Article
• Authors: Bortolami, Giovanni; Farolfi, Elena; Badel, Eric; Burlett, Regis; Cochard, Herve; Ferrer, Nathalie; King, Andrew; Lamarque, Laurent J; Lecomte, Pascal; Marchesseau-Marchal, Marie; Pouzoulet, Jerome; Torres-Ruiz, Jose M; Trueba, Santiago; Delzon, Sylvain; Gambetta, Gregory A; Delmas, Chloe E L
• Editors: Turner, Simon
• Is Part Of: Journal of experimental botany. Volume 72:Number 10(2021)
• Page Start: 3914
• Page End: 3928
• Publication Date: 2021-03-15
• Subjects: Esca -- hydraulic failure -- plant dieback -- tyloses -- vascular pathogens -- Vitis vinifera L -- X-ray microCT -- xylem anatomy; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erab117
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract : Esca critically affects xylem water movement in grapevine perennial organs by the presence of plant-derived tyloses. Abstract: Hydraulic failure has been extensively studied during drought-induced plant dieback, but its role in plant-pathogen interactions is under debate. During esca, a grapevine ( Vitis vinifera ) disease, symptomatic leaves are prone to irreversible hydraulic dysfunctions but little is known about the hydraulic integrity of perennial organs over the short- and long-term. We investigated the effects of esca on stem hydraulic integrity in naturally infected plants within a single season and across season(s). We coupled direct ( k s ) and indirect ( k th ) hydraulic conductivity measurements, and tylose and vascular pathogen detection with in vivo X-ray microtomography visualizations. Xylem occlusions (tyloses) and subsequent loss of stem hydraulic conductivity ( k s ) occurred in all shoots with severe symptoms (apoplexy) and in more than 60% of shoots with moderate symptoms (tiger-stripe), with no tyloses in asymptomatic shoots. In vivo stem observations demonstrated that tyloses occurred only when leaf symptoms appeared, and resulted in more than 50% loss of hydraulic conductance in 40% of symptomatic stems, unrelated to symptom age. The impact of esca on xylem integrity was only seasonal, with no long-term impact of disease history. Our study demonstrated how and to what extent a vascular disease such as esca, affecting xylem integrity, could amplify plant mortality through hydraulic failure.