Advances in understanding stilbene (resveratrol, ε-viniferin) -grapevine relationships

The paper reviews previous and not yet published results on some aspects of stilbene phytoalexin (resveratrol, ɛ-viniferin and pterostilbene) physiology in grapevine, obtained by the Viticulture Institute of the Catholic University at Piacenza. The effect of mineral nutrition on induced resveratrol and ɛ-viniferin synthesis has been investigated emphasizing the role of nitrogen, wich decreases stilbene leaf levels, and potassium, which increases them. Time course of stilbene accumulation in leaves and berries of different genotypes artificially infected with Botrytis cinerea, is reported. The paper describes also an attempt to get immunization against downy mildew, by spraying plants with an abiotic elicitor (mucic acid). Constitutive resveratrol contents of bunch stems and roots are described, as well as the possible role of cluster stems as resveratrol source in wine.