ABSTRACT
Sour rot of grapes is a serious disease mainly affecting varieties with dense bunches, near the harvest. Disintegration of bunch, acetic acid smell and presence of fruit flies are the typical symptoms. In North and Central Italy yeasts and acetic bacteria, which enter the berries through wounds of any kind, are the pathogens. The most frequent yeasts include Kloeckera apiculata, Saccharomycopsis vini, Hanseniaspora uvarum and so on. Because of the biological nature of the sour rot pathogens, no direct chemical control is possible particularly on wine grape near the harvest time. Integrated chemical control of berry wound agents, such as powdery mildew, grey mould and grape caterpillars produced a significantly reduction in the disease. Use of insecticides against fruit flies such as Drosophila spp., which are important vectors of the pathogenic agents of the sour rot, is not always satisfactory. Use of plastic nets or cheesecloth to prevent the infestation of fruit flies was one of the best methods to control the sour rot in fruit-store during the raisining for the production of strong sweet wines. A suitable cropping system to prevent skin wounds and the use of clones with less dense bunches and more resistant berry skins are, in any case, recommended.
