EFFECT OF BORDEAUX MIXTURE SPRAY ON FRUIT QUALITY OF ‘KYOHO’ GRAPE AND COPPER ACCUMULATION IN THE SOIL

In 2008, residual copper contents in soils of Korean vineyards under different Bordeaux mixture spray programs were determined.
In all 25 vineyards tested, copper contents in the soil were below the 50 mg kg^-1 soil maximum contamination standard.
However, as the number of sprays increased, the residual copper content also increased.
The effects of Bordeaux mixture on ‘Kyoho’ grape quality and incidence of downy mildew were also investigated.
Grape quality was improved in many Bordeaux mixture treated blocks because most leaves were not infected with downy mildew (Plasmopara viticola). The effect of bagging ‘Kyoho’ grape bunches before spraying with Bordeaux mixture was also determined.
Grape bunches without paper bags had poor appearance, which reduces the market price, and elevated copper levels in the grape juice.
Copper concentration in the naked bunches sprayed with Bordeaux mixture was close to the maximum limit of 20 mg kg^-1 fruit for table grapes.

II International Organic Fruit Symposium

S.M. Jung, J.C. Nam, Y.Y. Huh, J.H. Roh, K.S. Park, T.J. Lim

organic fungicide, downy mildew, bagging

https://doi.org/10.17660/ActaHortic.2013.1001.29