Gas Exchange, Stem Water Potential and Xylem Flux on Some Grapevine Cultivars Affected by Esca Disease

Abstract

The effect of esca disease on gas exchange, stem water potential and xylem flux of adult grapevines of Cabernet Sauvignon, Sangiovese and Trebbiano cultivars was studied over three growing seasons. Water relations were measured at véraison and cluster ripening on three types of vines: i) healthy (control); ii) symptomatic and iii) apparently healthy in the year of measurements but that had showed esca symptoms in the previous season. Xylem flux was determined on cane segments by perfusion using a tracing dye before and after the appearance of esca symptoms. Esca induced a marked reduction (about 70%) in carbon assimilation and stomatal conductance, especially in Cabernet Sauvignon and Sangiovese. Esca did not affect the stem water potential. Gas exchange parameters measured before the symptoms appeared in plants affected by esca were similar to those of healthy plants. Measurements made one month before the appearance of the symptoms cannot be used as screening method to determine whether the vine will show esca. No differences in dye translocation were found before the symptoms' appearance. However, a decrease in xylem flux was measured in symptomatic vines of Cabernet Sauvignon. After the appearance of esca symptoms, only the Trebbiano had a lower xylem flux than the healthy vines.

Cultivar Susceptibility to Natural Infections Caused by Fungal Grapevine Trunk Pathogens in La Mancha Designation of Origin (Spain)

“…minimun in greenhouse [17] and field [12] conditions. In contrast, 'Cabernet Sauvignon' was considered a susceptible cultivar to esca natural infection under field conditions in Italy [27,[36][37][38], and Australia [20], which is in agreement with the results of our study. 'Tempranillo' cultivar has also been widely evaluated to esca disease susceptibility.…”

Current knowledge on Grapevine Trunk Diseases with complex etiology: a systemic approach

“…Unlike the "toxins" hypothesis, where tiger stripelike symptoms are observed after toxin injection into healthy detached leaves, the "hydraulic dysfunction" hypothesis shows no similarity with tiger stripe-like FS. Tiger-stripe symptoms are not visually or physiologically similar to typical grapevine symptoms of edaphic water stress (Christen et al, 2007;Andreini et al, 2009;Letousey et al, 2010;Fontaine et al, 2016;Reis et al, 2016). FS can show similarities with symptoms of folletage described by Branas (1974), or to some senescence symptoms in autumn.…”

“…Some studies have been dedicated to characterizing the physiological disturbance that occurs on symptomatic leaves showing esca disease or Botryosphaeria dieback, or on asymptomatic leaves from symptomatic canes, and prior to the outburst of FS (Petit et al, 2006;Christen et al, 2007;Andreini et al, 2009;Letousey et al, 2010;Valtaud et al, 2011). This has been reviewed by Wagschal et al (2008) and Fontaine et al (2016).…”

“…The impact of wood necrosis or the presence of wood inhabiting fungi on vine hydraulics have not been intensively studied, except for Pch infections on young plants (Edwards et al, 2007;Fischer and Kassemeyer, 2012) or some measurements of resistance to sap flow (Andreini et al, 2009). Recent research (Bortolami et al, 2019) has advanced this area, and is likely to open new research on the hydraulic dysfunction hypothesis.…”

Overview of the Esca Complex as an Increasing Threat in Vineyards Worldwide: Climate Change, Control Approaches and Impact on Grape and Wine Quality

“…Esca is considered as a catastrophic, non-selective grapevine disease, and remedies such as specialised fungicides or totally resistant varieties do not exist [17,58]. Nevertheless, various V. vinifera cultivars present different levels of susceptibility or resistance to the pathogens.…”