Semi-Targeted Profiling of the Lipidome Changes Induced by in Disease-Resistant and L. Varieties.

The ascomycete is a serious pathogen in viticulture. Despite the fact that some grapevine genotypes exhibit mono-locus or pyramided resistance to this fungus, the lipidomics basis of these genotypes' defense mechanisms remains unknown. Lipid molecules have critical functions in plant defenses, acting as structural barriers in the cell wall that limit pathogen access or as signaling molecules after stress responses that may regulate innate plant immunity.

Secondary and primary metabolites reveal putative resistance-associated biomarkers against in resistant grapevine genotypes.

Numerous fungicide applications are required to control , the causative agent of powdery mildew. This increased demand for cultivars with strong and long-lasting field resistance to diseases and pests. In comparison to the susceptible cultivar 'Teroldego', the current study provides information on some promising disease-resistant varieties (mono-locus) carrying one resistant locus: BC4 and 'Kishmish vatkana', as well as resistant genotypes carrying several resistant loci (pyramided): 'Bianca', F26P92, F13P71, and NY42.

Mono-Locus and Pyramided Resistant Grapevine Cultivars Reveal Early Putative Biomarkers Upon Artificial Inoculation With .

One of the most economically important grapevine diseases is Downy mildew (DM) caused by the oomycete . A strategy to reduce the use of fungicides to compensate for the high susceptibility of is the selection of grapevine varieties showing pathogen-specific resistance. We applied a metabolomics approach to evaluate the metabolic modulation in mono-locus resistant genotypes carrying one locus associated with resistance () (BC4- , Bianca- , F12P160- , Solaris- ), as well as in pyramided resistant genotypes carrying more than one (F12P60- and F12P127- ) taking as a reference the susceptible genotype Pinot Noir.

Two-omics data revealed commonalities and differences between Rpv12- and Rpv3-mediated resistance in grapevine.

Plasmopara viticola is the causal agent of grapevine downy mildew (DM). DM resistant varieties deploy effector-triggered immunity (ETI) to inhibit pathogen growth, which is activated by major resistance loci, the most common of which are Rpv3 and Rpv12. We previously showed that a quick metabolome response lies behind the ETI conferred by Rpv3 TIR-NB-LRR genes.

Emergent Ascomycetes in Viticulture: An Interdisciplinary Overview.

The reduction of pesticide usage is a current imperative and the implementation of sustainable viticulture is an urgent necessity. A potential solution, which is being increasingly adopted, is offered by the use of grapevine cultivars resistant to its main pathogenic threats. This, however, has contributed to changes in defense strategies resulting in the occurrence of secondary diseases, which were previously controlled.

The Haplotype and Stilbenoid Induction Mediate Downy Mildew Resistance in a Grapevine Interspecific Population.

The development of new resistant varieties to the oomycete (Berk.& Curt) is a promising way to combat downy mildew (DM), one of the major diseases threatening the cultivated grapevine ( L.).

Identification of Biomarkers for Defense Response to in a Resistant Grape Variety.

Downy mildew () is one of the most destructive diseases of the cultivated species . The use of resistant varieties, originally derived from backcrosses of North American spp., is a promising solution to reduce disease damage in the vineyards.

Lipid, phenol and carotenoid changes in 'Bianca' grapevine leaves after mechanical wounding: a case study.

Metabolic changes can occur in plants in response to abiotic stress. Extensive use of leaf discs (mechanical wounding) in studies regarding the effect on the biochemical response of the grapevine to different types of biotic stress makes it necessary to understand metabolic perturbation after injury. In this study, we investigate how mechanical wounding can affect the metabolism of grapevine leaf tissue using Bianca variety as case study.

Resistance to Plasmopara viticola in a grapevine segregating population is associated with stilbenoid accumulation and with specific host transcriptional responses.

Background: Downy mildew, caused by the oomycete Plasmopara viticola, is a serious disease in Vitis vinifera, the most commonly cultivated grapevine species. Several wild Vitis species have instead been found to be resistant to this pathogen and have been used as a source to introgress resistance into a V. vinifera background.

Profiling of resveratrol oligomers, important stress metabolites, accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola.

In the Vitaceae, viniferins represent a relatively restricted group of trans-resveratrol oligomers with antifungal properties, thus enabling plants to cope with pathogen attack. The aim of this study was to perform isolation and structural characterization of the whole class of viniferins accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola . Infected leaves of resistant plants were collected 6 days after infection, extracted with methanol, and prepurified by flash chromatography using ENV+ and Toyopearl HW 40S resins.

Inhibition of Sporulation and Ultrastructural Alterations of Grapevine Downy Mildew by the Endophytic Fungus Alternaria alternata.

ABSTRACT One hundred twenty-six endophytic microorganisms isolated from grapevine leaves showing anomalous symptoms of downy mildew were tested on grapevine leaf disks as biocontrol agents against Plasmopara viticola. Among the 126 microorganisms, only five fungal isolates completely inhibited the sporulation of P. viticola; all of them were identified as Alternaria alternata.

Antifungal activity of diketopiperazines extracted from Alternaria alternata against Plasmopara viticola: an ultrastructural study.

Three dipeptides, belonging to the family of diketopiperazines (DKPs), were extracted from broth culture of the grapevine endophyte Alternaria alternata, and were tested against Plasmopara viticola on leaves of grapevine plants grown in greenhouse. DKPs, used at different concentrations (10(-3), 10(-4), 10(-5) and 10(-6)M) both singularly and in mixtures, demonstrated real effectiveness in inhibiting P. viticola sporulation when applied 2 or 24h after pathogen inoculation.

Ultrastructural analysis of Vitis vinifera leaf tissues showing atypical symptoms of Plasmopara viticola.

In an abandoned farm in Tuscany a year by year regression of downy mildew disease on grapevines was observed and a decrease in virulence as well as vigor and fertility of the causal fungus, Plasmopara viticola. Anomalous spots of the fungus (i.e.

Development of a standard set of microsatellite reference alleles for identification of grape cultivars.

In order to investigate the comparability of microsatellite profiles obtained in different laboratories, ten partners in seven countries analyzed 46 grape cultivars at six loci (VVMD5, VVMD7, VVMD27, VVS2, VrZAG62, and VrZAG79). No effort was made to standardize equipment or protocols. Although some partners obtained very similar results, in other cases different absolute allele sizes and, sometimes, different relative allele sizes were obtained.