Researches on Cholinesterases and Plant Protection

Abstract

Acetylcholinesterases (AChEs) are enzymes which are intensively studied by a multidisciplinary approach including biochemistry, molecular biology and molecular genetics. Insecticides and nematicides of the organophosphate (OP) and carbamate (CB) families act by inhibiting acetylcholinesterase activity. Thus, agriculture is one of the great socioeconomic activity which should benefit from the increasing knowledge on AChEs, leading to a revival of the use of these pesticides. These products are used both in phytoprotection and to treat some vectors of human diseases like malaria. In the fifties, OP and CB represented more than 50% of the market of pesticides, a proof of their effectiveness. They currently account for only 30% of this market. Two main scientific reasons explain this reduction: 1) the appearance of resistance in target organisms and 2) the toxicity of these products with respect to the users, the consumers and the environment. I show here how the new knowledge on AChEs could progressively circumvent these problems. Biotechnology could render these products safer and more effective tools to control even resistant pest populations, with reduced disadvantages for environment and health. In particular, one promising issue is to find new products, more specific, less reactive and thus less dangerous for man and its environment.