RT Journal Article
SR Electronic
T1 Phytochemical Concentrations and Antioxidant Capacity of Grapes Treated with Low Copper Formulations against Downy Mildew
JF American Journal of Enology and Viticulture
JO Am. J. Enol. Vitic.
FD American Society for Enology and Viticulture
SP 486
OP 492
DO 10.5344/ajev.2014.14028
VO 65
IS 4
A1 Anna La Torre
A1 Paolo Menesatti
A1 Marta Fibiani
A1 Valentina Picchi
A1 Claudio Mandalà
A1 Francesca Antonucci
A1 Roberto Lo Scalzo
YR 2014
UL http://www.ajevonline.org/content/65/4/486.abstract
AB A two-year study was conducted in an organic vineyard to evaluate the phytochemical concentrations and antioxidant capacity of grapes treated with low copper for downy mildew control compared to grapes that were untreated or treated with a standard fungicide. The metabolic profile, antioxidant capacity, and downy mildew incidence and severity were assessed. The maturity of grapes was an important factor in determining the potential risk for the spread of fungal disease, as suggested by principle components analysis (PCA), which showed a positive relationship between tartaric acid concentration and both incidence and severity of downy mildew disease. Polyphenols and thiols were more abundant in berries with less disease. The thiols were highly correlated with the antioxidant capacity, indicating an important role of these metabolites in determining the antioxidant potential of grape berries. Moreover, both the antioxidant indexes and thiols in the PCA were plotted opposite the disease severity and incidence, suggesting that higher antioxidant potential may be responsible for an increased capacity of grapes to counteract the disease. Results showed that low-copper formulations could control grape downy mildew in the field with a similar efficacy to the standard reference fungicide, without affecting the phytochemical profile and the antioxidant potential of grapes. Low-copper formulations may be thus considered alternatives for organic agriculture that minimize costs and copper accumulation in the soil, thus ensuring grape quality in a sustainable crop management system.