1a. Objectives (from AD-416)
Improve the quality and storage life of table grapes by the application of sprays directed into grape clusters in vineyards before harvest.
1b. Approach (from AD-416)
In repeated cluster-directed applications between fruit set and harvest, apply calcium salts, hormonal treatments, reduced-risk fungicides, biological control agents, and other compounds before harvest, then determine their influence postharvest quality (color, texture, maturity, size) and decay (natural incidence of diseases, after artificial inoculation) of table grapes. Documents Trust with CA Table Grape Commission. Log 35964.
3. Progress Report
This is a new project; the first invoice from the California Table Grape Commission to support this work was received in August, 2008. Postharvest quality is an important aspect of table grapes marketing, but the influence of antifungal materials (such as conventional and certified ‘organic’ fungicides, growth regulators, and mineral nutrients) applied repeatedly directly into table grape clusters during the growing season before harvest on the quality, maturity, and incidence of decay pathogens long after storage is poorly known. In 2007 and repeated in 2008, trials were conducted in several vineyards where mineral nutrients, GRAS substances, and biological control agents were applied repeatedly before harvest, and preliminary results showed substantial improvements in berry quality could be made by these actions. Cooperator activity is monitored by the use of e-mails, phone calls and site visits.