Search results for "Grapevine"

Fungal pathogens associated with grapevine trunk diseases in young vineyards in Sicily

2020

After the first report of grapevine decline caused by Botryosphaeriaceae in Sicily in 2007, epidemiological studies carried out in mature vineyards until 2011 confirmed the widespread occurrence of “Botryosphaeria dieback” and the “Esca complex” disease. Dieback symptoms were also recently observed in two young vineyards in Partanna and Castellammare del Golfo in western Sicily (Trapani province). Declining vines were inspected for grapevine trunk disease (GTD) symptoms, and were uprooted and submitted for analyses. Fungal isolates were collected and identified using culturing and molecular analyses. One isolate per identified species was inoculated to three grapevine shoots to evaluate pat…

Upscaling leaf gas exchange measurements to the whole grapevine canopy: An update

2009

This review first revisits current knowledge about single-leaf function, viz. photosynthesis, chiefly in relation to environmental factors, that underscores the importance of multiple summer stresses. Emphasis is placed on the response different genotypes show under light and heat stress with or without soil-water shortage. Secondly, it tackles the thorny issue of extrapolating single-leaf readings to the whole-canopy level, with special reference to both methodological and physiological implications. Whole-canopy gas-exchange systems deliver and emphasise the usefulness of such an approach in achieving key research goals. One case in point is quantifying the amount and dynamics of canopy g…

Analyse spectrale et texturale de données à haute résolution pour la détection automatique des maladies de la vigne

2019

‘Flavescence dorée’ is a contagious and incurable disease present on the vine leaves. In order to contain the infection, the regulations require growers to control each of the vine rows and to remove the suspect vine plants. This monitoring is done on foot during the harvest and mobilizes many people during a strategic period for viticulture. In order to solve this problem, the DAMAV project (Automatic detection of Vine Diseases) aims to develop a solution for automated detection of vine diseases using a micro-drone. The goal is to offer a turnkey solution for wine growers. This tool will allow the search for potential foci, and then more generally any type of vine diseases detectable on th…

Climate projections over France wine-growing region and its potential impact on phenology

2022

Climate change represents a major challenge for the French wine industry. Climatic conditions in French vineyards have already changed and will continue to evolve. One of the notable effects on grapevine is the advancing growing season. The aim of this study is to characterise the evolution of agroclimatic indicators (Huglin index, number of hot days, mean temperature, cumulative rainfall and number of rainy days during the growing season) at French wine-growing regions scale between 1980 and 2019 using gridded data (8 km resolution, SAFRAN) and for the middle of the 21th century (2046-2065) with 21 GCMs statistically debiased and downscaled at 8 km. A set of three phenological models were …

Study of the variability of an endophytic Acremonium population in symptomless grapevines.

2009

Epidemiological Survey of Grapevine Leafroll-Associated Virus 1 and 3 in Sicily (Italy): Genetic Structure and Molecular Variability

2022

Background: the most widely distributed and virulent Grapevine leafroll-associated viruses (GLRaV) that affect grapevine are GLRaV-1 and GLRaV-3, transmitted semi-persistently by different mealybugs and soft scales, mainly causing downward rolling of the leaf margins and interveinal reddening. Methods: the main objectives of this study were to investigate the genetic structure and molecular diversity of GLRaV-1 and GLRaV-3 in 617 samples from 11 autochthonous Sicilian grapevine cultivars, ascertaining their presence and spread. The detection was implemented by serological and molecular analyses and subsequently phylogenetic analyses on selected Sicilian isolates were conducted. Results: in …

Evolutionary Analysis of Grapevine Virus A: Insights into the Dispersion in Sicily (Italy)

2022

Grapevine virus A (GVA) is a phloem-restricted virus (genus Vitivirus, family Betaflexiviridae) that cause crop losses of 5–22% in grapevine cultivars, transmitted by different species of pseudococcid mealybugs, the mealybug Heliococcus bohemicus, and by the scale insect Neopulvinaria innumerabilis. In this work, we studied the genetic structure and molecular variability of GVA, ascertaining its presence and spread in different commercial vineyards of four Sicilian provinces (Italy). In total, 11 autochthonous grapevine cultivars in 20 commercial Sicilian vineyards were investigated, for a total of 617 grapevine samples. Preliminary screening by serological (DAS-ELISA) analysis for GV…

Diversity of Diatrypaceae species in three Spanish grapevine producing regions.

2015

The objective of this study was to identify species of Diatrypaceae associated with trunk diseases in three different Spanish grapevine producing regions: Albacete, Cádiz and Valencia provinces, located, respectively, in geographically distant areas of Central, South and Eastern Spain. Species identification of 71 isolates was performed using a combination of morphological characters and phylogenetic analyses based on the internal transcribed spacer regions of the rDNA (ITS) and the β-tubulin gene. Four species of Diatrypaceae were identified: Cryptovalsa ampelina was the predominant species (63.4%) followed by Eutypa lata (19.7%), Eutypella microtheca (4.2%), and Eutypella citricola (2.8%)…

"In vitro" antagonism of a grapevine endophytic Bacillus subtilis strain towards "esca" fungi.

2008

Preliminary investigations on grapevines (CV Catarratto) with symptoms of “esca” permitted to isolate only bacterial colonies, from black punctuations belonging to the genus Bacillus. Particularly, an isolate was Gram-positive with spore forming and, on the basis of the partial 16S rRNA sequence comparison, it showed a similarity of 99% with Bacillus subtilis subsp. subtilis. There are numerous reports on the antagonistic activity of the species towards several phytopathogenic microorganisms. For this reason the possible bacterial control against the “esca” fungi (Phaeoacre- monium aleophilum, PAL; Phaemoniella clamidospora, PCH; Fomitiporia mediterranea, FOMED), was studied. The antagonist…

Activation of Grapevine Defense Mechanisms: Theoretical and Applied Approaches

2011

part 4.; International audience; Grapevine, as other plants, possesses an innate immune system that usually prevents infection by pathogens. General elicitors are compounds of different biochemical families capable of inducing plant defense reactions. In grapevine, the cascade of defense events induced by elicitors has been studied among others in cell suspensions. The perception of the elicitor triggers signaling events that allow the activation of defense genes encoding PR proteins and other proteins involved in phytoalexin production and cell wall reinforcement. The grapevine phytoalexins resveratrol and derivated compounds have been largely studied. In addition to their antimicrobial ac…