| Organic apple production in Europe depends to a great extent on the use of copper fungicides for scab control (Venturia inaequalis). The objective of this 6-year study (2003-2008) conducted in Belgium was to determine measures for reducing the use of copper fungicides in organic apple production. The effectiveness of a “during-infection” spray strategy using wettable sulphur (with or without copper), lime sulphur, potassium bicarbonate, silicon and five natural plant extracts (orangepeel, soapbark, tea seed, quinoa seed and grapefruit seed) for controlling primary scab was investigated in a split-plot field experiment. Four apple cultivars that express a gradient of partial scab resistance were included: a high scab-susceptible cultivar (cv. ‘Pinova’), a... |
