Project RELACS – Improving inputs for organic farming. The greenhouse whitefly, Trialeurodes vaporariorum causes direct damage to plants by piercing their tissues, as well as indirect damage, by transmitting viruses. Mineral oils are usually applied to control the greenhouse whitefly but should be replaced with more sustainable solutions.

Powdery mildew (PM) caused by Podosphaera xanthii is one of the most important courgette diseases with high yield losses and is currently controlled by fungicides and sulphur applications in conventional and organic production. Plant derived elicitors/inducers of resistance are natural compounds that induce resistance to pathogen attack and promote a faster and/or more robust activation of plant defense responses. Giant knotweed (Reynoutria sachalinensis, RS) extract is a known elicitor of plant defenses but its mode of action remains elusive.