title: Antifungal modes of action of Saccharomyces and other biocontrol yeasts against fungi isolated from sour and grey rots.
abstract: The aim of this study was to determine the putative modes of action of 59 viticultural yeasts (31 Saccharomyces and 28 non-Saccharomyces) that inhibited fungi isolated from sour and grey rot in grapes. Inhibition of fungal mycelial growth by metabolites, enzyme activities (laminarinases, chitinases), antifungal volatiles, competition for nutrients (siderophores, Niche Overlap Index (NOI)), inhibition of fungal spore germination and decreased germinal tube length and induction of resistance were assayed. Biofungicide yeasts were classified into "antifungal patterns", according to their mechanisms of action. Thirty isolates presented at least two of the mechanisms assayed. We propose that inhibition of fungal mycelial growth by metabolites, laminarinases, competition for nutrients, inhibition of fungal spore germination and decreased germinal tube length, and antifungal volatiles by Saccharomyces and non-Saccharomyces viticultural yeasts is used as putative biocontrol mechanisms against phytopathogenic fungi. Twenty-four different antifungal patterns were identified. Siderophore production (N)and a combination of siderophore production and NOI>0.92 (M)were the most frequent antifungal patterns observed in the biofungicide yeasts assayed. Elucidation of these mechanisms could be useful for optimization of an inoculum formulation, resulting in a more consistent control of grey and sour rot with Saccharomyces and non-Saccharomyces biocontrol yeasts.
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina. Electronic address: cristinanally@yahoo.com.ar.
authors: M C
authors: MC
authors: Nally
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina.
authors: V M
authors: VM
authors: Pesce
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina.
authors: Y P
authors: YP
authors: Maturano
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina.
authors: L A
authors: LA
authors: Rodriguez Assaf
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina.
authors: M E
authors: ME
authors: Toro
authors: PROIMI, Planta Piloto de Procesos Industriales Microbiológicos, Av. Belgrano y Pasaje Caseros, CP4000 Tucumán, Argentina; FBQyF-UNT, Facultad de Bioquímica, Química y Farmacia, Ayacucho 455,CP4000 Tucumán, Argentina.
authors: L I
authors: LI
authors: Castellanos de Figueroa
authors: IBT, Instituto de Biotecnología-Facultad de Ingeniería-Universidad Nacional de San Juan, Av. Libertador San Martín 1109 oeste, CP5400 San Juan,Argentina.
authors: F
authors: F
authors: Vazquez
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D020171:Botrytis / Q000187:drug effects; D044602:Cellulases / Q000378:metabolism; D002688:Chitinases / Q000378:metabolism; D025282:Mycelium / Q000187:drug effects / Q000254:growth & development; D010935:Plant Diseases / Q000382:microbiology* / Q000517:prevention & control*; D012440:Saccharomyces / Q000302:isolation & purification / Q000378:metabolism*; D013172:Spores, Fungal / Q000187:drug effects; D027843:Vitis / Q000382:microbiology*
chemical_list: D000935:Antifungal Agents; D044602:Cellulases; D002688:Chitinases
keywords: Antifungal patterns; Grape; Possible action mechanisms; Saccharomyces biofungicides