Presentation of grapevine trunk diseases and their impact on plant physiology

Transcription

1 Presentation of grapevine trunk diseases and their impact on plant physiology Florence FONTAINE University of Reims Champagne-Ardenne, France Peso da Réga, Portugal November 10 th, 2015

2 Background & Problematic Grapevines Cultivars GTD(s) Esca-proper Apoplexy event? Eutypa dieback Apoplexy event Botryosphaeria dieback Apoplexy event Vine physiology Portugal France Italia Switzerland Spain Geographic localisation USA Hungary Australia

3 Pathogens wood inhabiting vessel complex of pathogens infection by wounds wood decay 1, 2, 3 years later latency period foliar symptom expression Death of the plant

4 Eutypa dieback Causal agent: Eutypa lata Dwarf & stunted shoots Chlorotic leaves Brown necrosis Loss in mature vineyards: 19 to 50% of yield

5 Esca disease Causal agents: Phaeoacremonium aleophilum, Phaemoniella chlamydospora, Fomitiporia mediterranea, Chronic & apoplectic form Discoloration on leaves Shrivelled berries White rot in the center Brown necrosis Black streaking

6 Botryosphaeria dieback Causal agents: Diplodia seriata, Neofusicoccum parvum, Botryosphaeria sp, Chronic & apoplectic form Discoloration on leaves Spot on berries Grey necrosis Brown streaking under the bark

7 Common points Affect young and mature vineyards Presence of pathogens in nurseries and on mother-plants Fluctuation of foliar symptoms expression over the years Main of causal agents infected the trunk of vines No resistant cultivars, different susceptibility No efficient strategies to control GTDs

8 Background & Problematic Environment Cultivars, rootstock, age Training system Physiological status of plant, Predisposing factors «Healthy plants» wood decay, no foliar symptoms Contributing factors Pathogen fungi Push factors Drought, Rainfall,.. GTDs, foliar symptoms.

9 GTDs & vine physiology healthy plant without foliar symptoms Esca-proper apo eutypa Berry Leaf Green stem Trunk Control plant White wood Black streaked Brown stripe Diseased plant

10 Leaf Green stem Inside the trunk - compartmentalization Wood Trunk Brown stripe Several fungi, pathogens and beneficial, and bacteria Wall 1 (M1) resulted in formation of tylosis in vessels. Wall 2 (M2) is formed by cells of the growth ring, limiting the inward of necrosis. Wall 3 (M3) is formed by rays cells and created a barrier to the lateral growth of decay. Wall 4 (M4) is created by new growth on the exterior of the trunk, like that new tissue produced could be healthy. CODIT model First plant responses: compartmentalization to form walls around the pathogen infection, slowing or preventing the spread of pathogens and the decay Shigo and Marx, Bruez, 2013

11 Inside the trunk occluded vessels Leaf Green stem White wood: functioning vessels Trunk Wood Brown stripe Black streaked Tylosis, not functional Occluded vessel Pouzoulet et al., 2014 Loss of vascular system function Susceptibility of cultivars correlated to large vessel diameter

12 Inside the trunk wood degradation Example in Botryosphaeria sp. Enzymes that degrade wood tissue Main enzymes: amylases, cellulases, xylanases, pectinases, pectin lyases, proteases, lipases, laccases. Fungi secrete secondary metabolites which ones are phytotoxic Rudelle et al., Rolshausen et al., Agrelli et al., 2009 Andolfi et al., Esteve et al., 2014 Abou-Mansour et al., 2015

13 Inside the trunk metabolisms affected Functional classification of identified proteins from trunk Induction of defense responses to limit the spread of pathogens. Amalfitano et al., 2011 Spagnolo et al., 2014 Magnin-Robert et al., 2014

14 Inside the trunk wood defense Anti-fungal compounds: stilbene polyphenols. Trunk Brown-Red Wood : BRW Asymptomatic Wood : AW Anti-fungal compounds: accumulated in brown-red wood. Amalfitano et al., 2011

15 Green stem physiological alteration? Leaf Trunk Green stem No pathogens E ae A aa Proteins Wood Brown stripe Plant responses? Modifications BUT Asymptomatic green stems (esca proper, apoplexy): similar changes Symptomatic green stems esca-proper / apoplexy : differences Control Esca proper Apoplexy Chardonnay 28 differentially expressed protein spots analyzed by nano-lc-ms/ms Defense response Stress tolerance Metabolism & energy Link to the form of disease expression? Spagnolo et al., 2012

16 Leaves photosynthesis disturbance? Esca proper No pathogens intensity No alteration of photosynthesis Pn? defense gene control plant photosynthesis (Pn) before foliar symptoms expression (D) and a decrease of starch storage in canes -> a decrease of the bud fertility D-14 D-7 D D+7 D+10 D+28 time (days) Petit et al., 2006 Magnin-Robert et al., 2011

17 Leaves photosynthesis disturbance? Apoplexy - Chardonnay intensity Pn defense gene control plant photosynthesis gene Photosynthesis affected on shoots 7 days before apoplexy, early detection D-20 D-7 D-2 D D+1 D+5 time (days) Differential responses according to the disease form Letousey et al., 2010

18 Berries alterations? Esca proper Sugars Nitrogen Tot. acidity Cabernet Sauvignon Percentages of esca fruit A delay in ripening of esca-affected fruit. Esca foliar symptoms impact stress-related pathways in skin grape. Esca moderately affects the phenolic composition of grape. Decreases the sensory quality of wines. Lorrain et al., Pasquier et al., 2013

19 Summary & prospect Diseased plant Berry Green stem Leaf Trunk Delay in ripening & Decrease on the sensory quality (Esca) Early perturbation of Pn before foliar symptoms expression (Apoplexy, Esca) Several physiological changes: carbohydrate metabolism, defense GST/stilbenes (Esca, Apoplexy, Botryosphaeria dieback, Eutypa dieback) Changes in metabolims linked to the form of disease expression (Esca proper, Apoplexy) Black streaked Brown stripe Formation of gummosis & tylosis Defense responses more linked to the discoloration in the wood than to the foliar symptom expression (Esca proper, Apoplexy) Defense responses are visibly activated in all these organs but they are probably not enough to avoid foliar symptom development Fontaine et al., 2015

20 Summary & perspectives All the organs of the vine react but not enough in some cases since foliar symptoms emerge Identify some markers (phenolic compounds, proteins, genes, ) Differential responses: GTDs, cultivars Control GTDs Development of friendly strategies and test their efficiency Plant physiology by induce defense responses Fight the pathogens

21 Thanks to Maryline Magnin Robert Catia Pinto Julie Vallet Alssandro Spagnolo Vincenzo Mondello Christophe Clément COST Action FA1303 Sustainable control of GTDs

22 THANK FOR YOUR ATTENTION