Aggressiveness of Ilyonectria spp. and “Cylindrocarpon” pauciseptatum associated with black foot disease of grapevine

Abstract

Since the 90's, black foot disease threatens grape production in many countries. Recently, new species associated to this disease have been described, but more studies related to their aggressiveness are necessary. Isolates of Ilyonectria macrodidyma, Ilyonectria robusta and "Cylindrocarpon" pauciseptatum obtained from grapevines with black foot symptoms collected in Rio Grande do Sul, Brazil, were inoculated on rooted cuttings of Vitis labrusca cv. Bordô and its root and aerial symptoms were evaluated. All isolates caused symptoms typical of the disease, including necrosis of the root and crown, as well as mass reduction of the canopy and of the root system. The isolates were reisolated from necrotic wood fragments, thus confirming their potential for damage on Vitis labrusca. Agressividade de Ilyonectria spp. e "Cylindrocarpon" pauciseptatum associados com a doença pé-preto da videiraRESUMO Desde a década de 90, a doença pé-preto ameaça a produção de uva em vários países. Recentemente, novas espécies associadas a esta doença têm sido descritas, necessitando de estudos avaliando sua agressividade. Isolados de Ilyonectria macrodidyma, Ilyonectria robusta e "Cylindrocarpon" pauciseptatum, obtidos de videiras com sintomas de pé-preto, foram coletados no Rio Grande do Sul, Brasil, e inoculados em estacas enraizadas de Vitis labrusca cv. Bordô e sintomas radiculares e aéreos foram avaliados. Todos os isolados originaram sintomas típicos da doença incluindo necrose em raízes e base da planta, além de redução de massa de parte aérea e raízes. Os isolados foram reisolados de fragmentos lenhosos necróticos confirmando, assim, seu potencial de dano em Vitis labrusca.Palavras-chave: declínio da videira, patogenicidade, patógenos de solo, Vitis spp.

Biocontrol of black foot disease on grapevine rootstocks using Bacillus subtilis strain F62

“…Antagonistic bacteria often act mainly by antibiosis mechanism and occasionally by parasitism and competition. Microorganisms of the former group usually have a broad spectrum of action, being the production of toxic substances more effective than other mechanisms involved in inhibition of pathogen growth (Santos et al 2015). Studies have shown the efficacy of B. subtilis in the control of vine fungal pathogen including Eutypa lata (Ferreira et al 1991;Kotze et al 2011), Botrytis cinerea and Colletotrichum gloeosporioides (Furuya et al 2011;Boubakri et al 2015), Phaeomoniella chlamydospora, Phomopsis viticola, Diplodia seriata, Lasiodiplodia theobromae, Neofusicoccum australe and N. parvum (Kotze et al 2011;Rezgui et al 2016), Plasmopara viticola (Furuya et al 2011;Boubakri et al 2015) and Dactylonectria macrodidyma (Santos et al 2016).…”

Molecular Characterization of Black Foot Disease Pathogens in Grapevine Nurseries and Evaluation of Some Fungicides for Control of the Most Virulent Isolates

“…The most commonly used and recommended biological control agents in the management of black foot disease were reported as Trichoderma Pers. species (Santos et al 2015). It has been found that Trichoderma members promote root growth of the plants which were predisposed to black foot disease and make them less vulnarable (Fourie & Halleen 2001).…”