Can we do without copper in organic crop protection? | Isabelle Savini, Didier Andrivon

Copper is used to control various fungal or bacterial diseases, mainly in vineyards, fruit production, and vegetable crops. It is the only active substance with a strong fungicidal effect and a wide range of action approved in organic agriculture. However, the identification of negative environmental effects of copper, especially on soil organisms, has led to regulatory restrictions on its use (limitation of authorized doses) and even to its prohibition as a pesticide in some Northern European countries. These increasing restrictions on the use of copper, which pose difficulties especially for producers who cannot resort to synthetic fungicides, have led to a recurring demand for "alternatives". Numerous experimental studies have been conducted to identify and test other techniques: the use of disease-resistant varieties, the application of natural substances with biocidal effects and/or stimulating the plants' natural defenses, the use of microbiological agents for control, the adoption of prophylactic cultivation practices, and the installation of physical protections. However, the results remain scattered, and these control methods are rarely implemented in the field. This book, resulting from collective scientific expertise, is a multidisciplinary and critical synthesis of the available knowledge on the subject. It presents and examines the various potentially effective techniques against pathogens controlled by copper treatments, and the need to combine them in integrated crop protection systems.