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Perspectives de lutte contre les maladies des arbres fruitiers à pépins au moyen de substances naturelles inductrices d'une résistance systémique

Biotechnologie, Agronomie, Société et Environnement 01/2002;
Source: DOAJ

ABSTRACT Natural compounds used as elicitors of systemic induced resistance offer new prospects to control pome fruit tree diseases. This review presents a new way of plant protection for pome fruit tree diseases as a potential response to the very high use of pesticides in commercial production with the view to reduce their negative side-effects on environment and human health. Work is focused on examples of use of elicitors from natural origin which induce systemic resistance for controlling two important diseases as apple scab (Venturia inaequalis) and fire blight (Erwinia amylovora). Many factors limit today their practical use: their efficacy is only partial and in interaction with plants and environment; much work has to be done to improve the formulation and to determine doses and rates of application, the right phenologic application times, and finally they are often submitted to the normal high standards of Plant Protection Products Regulations which are long, very expensive and not adapted to compounds which can have a very complex composition. In other hands, this new way of plant protection presents many potential advantages: using relatively simple, not expensive, non toxic natural compounds with a good image; polyvalent and broad field of action; non-specific and multi-side action which offer a good durability of action; systemic action in the plants during a relative long period of time and the possibility to control difficult bacterial diseases and more surprisingly viral diseases. The multiple advantages presented offer valuable prospects for a better friend-environmentally way to control pome fruit diseases in the next future.

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