Sap Flow Disruption in Grapevine Is the Early Signal Predicting the Structural, Functional, and Genetic Responses to Esca Disease.

Fungal species involved in Esca cause the formation of grapevine wood necroses. It results in the deterioration of vascular network transport capacity and the disturbance of the physiological processes, leading to gradual or sudden grapevine death. Herein, for two consecutive growing seasons, a detailed analysis of the structural (wood necrosis and leaf discoloration) and physiological parameters related to the water use of healthy and esca-symptomatic grapevines was conducted.

Impacts of Sodium Arsenite on Wood Microbiota of Esca-Diseased Grapevines.

Although sodium arsenite was widely used in Europe until its ban in 2003, its effects on microorganisms is not clearly understood. To improve our understanding of sodium arsenite curative effect on GTDs, grapevines displaying esca-foliar symptoms from different French regions (Alsace, Champagne, Languedoc) were treated or not with sodium arsenite, and analyzed for their wood microbiota. Using metabarcoding, we identified the fungal and bacterial taxa composition of microbiota colonizing woody trunk tissues.

Methyl salicylate, a grape and wine chemical marker and sensory contributor in wines elaborated from grapes affected or not by cryptogamic diseases.

Methyl salicylate (MeSA) is a plant metabolite that induces plant defence resistance and an odorous volatile compound presenting green nuances. This volatile compound was shown to be present in wine samples, sometimes at concentrations above its olfactory detection threshold. MeSA is localized in grapes, particularly in the skins and stems, and is extracted during red wine vinification.

The Biocontrol Root-Oomycete, , Triggers Grapevine Resistance and Shifts in the Transcriptome of the Trunk Pathogenic Fungus, .

The worldwide increase in grapevine trunk diseases, mainly esca, represents a major threat for vineyard sustainability. Biocontrol of a pioneer fungus of esca, , was investigated here by deciphering the tripartite interaction between this trunk-esca pathogen, grapevine and the biocontrol-oomycete, . When colonizes grapevine roots, it was observed that the wood necroses caused by were significantly reduced.

Major changes in grapevine wood microbiota are associated with the onset of esca, a devastating trunk disease.

Esca, a major grapevine trunk disease in old grapevines, is associated with the colonization of woody tissues by a broad range of plant pathogenic fungi. To identify which fungal and bacterial species are involved in the onset of this disease, we analysed the microbiota from woody tissues of young (10-year-old) grapevines at an early stage of esca. Using meta-barcoding, 515 fungal and 403 bacterial operational taxonomic units (OTUs) were identified in woody tissues.

Ecophysiological impacts of Esca, a devastating grapevine trunk disease, on Vitis vinifera L.

Esca is a Grapevine Trunk Disease (GTD) caused by a broad range of taxonomically unrelated fungal pathogens. These attack grapevine wood tissues inducing necroses even in the conductive vascular tissues, thus affecting the vine physiology and potentially leading to plant death. However, the influence of Esca on leaf and whole-plant water transport disruption remains poorly understood.

Bacterial Shifts in Nutrient Solutions Flowing Through Biofilters Used in Tomato Soilless Culture.

In soilless culture, slow filtration is used to eliminate plant pathogenic microorganisms from nutrient solutions. The present study focused on the characterization and the potential functions of microbial communities colonizing the nutrient solutions recycled on slow filters during a whole cultivation season of 7 months in a tomato growing system. Bacterial microflora colonizing the solutions before and after they flew through the columns were studied.

Bacteria in a wood fungal disease: characterization of bacterial communities in wood tissues of esca-foliar symptomatic and asymptomatic grapevines.

Esca is a grapevine trunk disease (GTD) associated with different pathogenic fungi inhabiting the woody tissues. Bacteria can also be found in such tissues and they may interact with these fungal colonizers. Although such types of microbial interactions have been observed for wood diseases in many trees, this has never been studied for grapevine.

Analyses of the temporal dynamics of fungal communities colonizing the healthy wood tissues of esca leaf-symptomatic and asymptomatic vines.

Esca, a Grapevine Trunk Disease (GTD), is of major concern for viticulture worldwide. Our study compares the fungal communities that inhabit the wood tissues of vines that expressed or not foliar esca-symptoms. The trunk and rootstock tissues were apparently healthy, whether the 10 year-old plants were symptomatic or not.

Effect of Temperature on Conidial Germination of Botryosphaeriaceae Species Infecting Grapevines.

Germination of conidia of eight botryosphaeriaceous fungi infecting grapevines was evaluated after 2, 4, 6, 12, and 24 h incubation under eight different temperatures (5, 10, 15, 20, 25, 30, 35, and 40°C). The effect of temperature on conidial germination was also evaluated in different stages (hyaline versus pigmented conidia) of the species Lasiodiplodia theobromae. Conidial germination of Botryosphaeriaceae species infecting grapevines was significantly affected by temperature.