Search results for "Botryosphaeria"
showing 5 items of 15 documents
Les maladies du bois de la vigne : recherches pour apporter des solutions de lutte aux Professionnels
2017
Les travaux réalisés sur deux maladies du bois de la vigne (esca, BDA) ont montré leur effet sur la récolte et la croissance de la pousse printanière qui était annulé deux années après l’apparition des symptômes. Ces maladies ont aussi conduit à des modifications des propriétés analytiques des moûts et des vins. Les vins issus de raisins collectés sur des ceps symptomatiques n’étaient pas toujours les plus dépréciés. Les études effectuées sur le cycle biologique ont permis de mettre au point des outils pour différencier les individus de deux espèces de Botryosphaeriaceae et des outils d’hybridation in situ qui permettront de les localiser précisément dans les tissus. Elles ont aussi identif…
Impact des maladies du bois sur le fonctionnement de la vigne
2020
Esca complex and Botryosphearia dieback are grapevine trunk diseases (GTDs) that cause severe declines in vineyards worldwide and against which the available control strategies are limited. These diseases are due to a complex of woody inhabiting fungi that colonize the perennial organs of grapevine throughout its life, from its production in nursery to the cultivation in the vineyard. The expression of foliar symptoms remains poorly understood and is influenced by many factors including climate, cultural practices and cultivar. In this context, this work aimed to characterize the impact of these two diseases on grapevine, at different spatial and temporal scales, in order to better understa…
Pathogenicity and possible biological control of fungi associated to Botryosphaeria dieback of grapevine in Western Sicily
2018
Botryosphaeria dieback is a widespread grapevine trunk disease caused by species of fungi within the family Botryosphaeriaceae. Symptoms of the disease include bud necrosis, leaf chlorosis, vascular discoloration of the wood, cankers and dieback. In 2013 typical symptoms of Botryosphaeria dieback was observed in Western Sicily and four species associated with the syndrome were isolated and identified as Diplodia seriata, Lasiodiplodia mediterranea, Neofusicoccum parvum and Neofusicoccum vitifusiforme. In order to fulfill Koch’s postulates, pathogenicity tests of eighteen isolates were performed on two-year grapevine cuttings of cv. Inzolia. Six months after inoculation all the Botryosphaeri…
First report of Diplodia africana on Grevillea robusta
2020
Branch cankers and dieback were observed on silky-oak trees (Grevillea robusta) along some streets of Palermo (Sicily, Italy). Fungi isolated from symptomatic branches were identified as Diplodia africana and D. seriata by morphological characters and phylogenetic analyses of combined ITS and translation elongation factor 1-α sequences. Pathogenicity was verified by inoculating twigs of 3-y-old silky-oak plants. This is the first report of D. africana on G. robusta and the first record of D. seriata on this host in the northern hemisphere.
Naphthalenone polyketides produced by Neofusicoccum parvum, a fungus associated with grapevine Botryosphaeria dieback
2016
A strain of Neofusicoccum parvum isolated from declining vines was pathogenic to grapevine cultivar Inzolia in Sicily. This strain produced some metabolites in liquid medium. Crude extract, through a bio-guided purification process, yielded four naphthalenone polyketides. They were identified by comparison with spectroscopic data and optical proprieties reported in literature as: (3S, 4S)-7-ethyl-3,4,8-trihydroxy-6-methoxy-3,4-dihydro-1-(2H)-naphthalenone, (3S*, 4S*)-3,4-dihydro-3,4,8-trihydroxy-7-(1-hydroxyethyl)-6-methoxy-1-(2H)-naphthalenone, (4S)-3,4-dihydro-4,8-dihydroxy-1-(2H)-naphthalenone, named botryosphaerones D and A, isosclerone, respectively, and (3S*,4S*)-3,4,5-trihydroxy-1-…