Erysiphe necator

Elemental S (crystalline or colloidal form) can accumulate as a residue in must as the result of its use as a vineyard agrochemical, where it is used to control grape vine powdery mildew Erysiphe necator and various pests. Direct reduction of S to H2S is induced by the highly reductive conditions that exist at the yeast cell surface during fermentation. This mechanism is of little practical importance except when the application of elemental S is not used according to manufacturers recommendations, such as application within the recommended with-holding period before grape harvest (Rankine 1963 Rauhut and Kiirbel 1994 Thomas et al. 1993). 

Brewer, M.T., Milgroom, M.G., 2010. Phylogeography and population structure of the grape powdery mildew fungus, Erysiphe necator, from diverse Yitis species. BMC Evol. Biol. 10, 268. 

Table 10.12 Evaluation of resistance to powdery mildew Erysiphe necator) in new cultivars. Standard cultivars are Riesling and Lemberger...

Cadle-Davidson, L., Chicoine, D.R., Consolie, N.H., 2011. Variation within and among Vitis spp. for foliar resistance to the powdery mildew pathogen Erysiphe necator. Plant Dis. 95, 202-211. 

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