Phytoalexines et réactions de défense de la tomate aux infections par Phytophthora parasitica et Verticillium albo-atrum

Abstract

Two cultivars of tomato of Saint-Pierre phénotype, isogenic for the resistance against verticilliosis and different for the resistance against mildew (and against Phytophthora parasitica Dast.), were inoculated with P. parasitica and with Verticillium albo-atrum Reinke et Berth. Associated with the defence reactions, an accumulation of sesquiterpenes phenolic compounds, tomatin, and oxygenated compounds of methyl linoleate took place in the tissues. Synthesis of these compounds in the host varies with the cultivars and the parasites in presence. In vitro studies on the inhibition of P. parasitica have shown an important synergism between the dienols on one side and the phenolic compounds and tomatin on the other side. [Translated by the Journal]