Strategies for organic control of tomato bacterial spot

Abstract: In this research the possibility has been verified to reduce current copper salt field doses (hydroxide) suggested to control Xanthomonas axonopodis pv. vesicatoria (Xav) (Doidge) Dye, the causal agent of tomato bacterial spot. In vitro and in planta tests were performed to evaluate and compare different botanical extracts and an essential oil (coumarin, gallic acid, carvacrol), alone or in combination, in respect to copper hydroxide. Plant extracts in combination with a reduced amount of copper salts, have been found to be as effective as the copper dosages recommended to date for control of Xav, proposing new biological strategies for the control of this dangerous pathogen.