If Swiss agriculture was to be converted to 100 % organic management, the number of plant protection products, in terms of active substances, would be reduced from currently 383 to 107 (28 %). Of the remaining 107 substances, 66 are living organisms, 15 pheromones and 26 are substances such as plant extracts, sulphur or copper. Under the «100 % organic farming» scenario, farmers would largely forego applications of plant protection products (PPP) in arable farming (23.6 % of the agricultural area AA), thus reducing the quantity of PPP applied there by 98.5 %. In the specialist crops of fruit, grapes, vegetables and potatoes (3 % of AA), PPP usage would be reduced by 20 %, and organic pesticides («chemically synthesised pesticides») would be replaced by other substances. On grassland (approximately 70 % of AA) PPP would no longer be used. Due to the major significance of direct crop protection in specialist crops, the overall quantities of PPP applied would initially only be reduced by 51 %. However, changes in crop rotations and in cultivar selection were not taken into account. A «100 % organic farming» scenario can be expected to result in a major reduction of the contamination with organic pesticides of watercourses, groundwater and food. Changes in crop production methods would contribute to improved delivery of ecosystem services such as biodiversity and soil fertility; however, this would probably result in lower yields per unit area. An extended study should be undertaken to clarify opportunities and challenges in terms of crop production, the environment and the markets.
The contribution of organic farming to reducing plant protection products in Switzerland