The aim of this study was to characterize the response to droughtstress induced in tomato plants treated with Megafol®, a bios-timulant provided by Valagro S.p.A that is known to positivelyinfluence crop yield (Para–dikovi´c et al., 2011), by collecting infor-mation regarding the physiological and molecular changes inducedby the stress and the potential positive effects, in terms of tolerance,due to the treatment. The physiological mechanisms were evalu-ated by image analysis (Scanalyzer 3D System, LemnaTec), usingvisible light (RGB), florescence, and near infra-red (NIR) chambers