Preharvest and Postharvest Practices to Extend the Shelf-life of Table Grapes

To develop preharvest and postharvest practices to extend the shelf-life of table grapes. Specific objectives include: 1) assemble a large collection of Botrytis cinerea isolates from numerous vineyards in the San Joaquin Valley and determine their sensitivity to fungicides; 2) determine the effectiveness of fungicides applied at various times in vineyards before harvest on the incidence of summer bunch rot and subsequent decay after harvest; 3) determine residue levels and their persistence at harvest and during cold storage, and the influence of sulfur dioxide or ozone gas on their persistence; 4) evaluate the effectiveness of periodic or cyclic low concentration ozone use during cold storage (as opposed to constant low ozone concentration), with or without weekly sulfur dioxide fumigation, to control postharvest decay.