Meeldauwprogrammeringstudie : studie mangaan en elicitor/groene gewasbeschermingsmiddelen over verschillende plant-meeldauwsystemen heen

Powdery mildew is still a major problem in greenhouse cultivation. This research was focused on preventive treatments of powdery mildew using nutrition en elicitors/green plant protection products to increase plant resilience. Investigations were conducted using different plant-mildew systems: 1. Pot gerbera - Podosphaera xanthii, 2. Sweet pepper – Leveillula taurica, 3. Kalanchoe - Oidium neolycopersicon en 4. Rose – Podosphaera pannosa. Plants were treated with manganese (Mn) concentrations of 5, 10, 20 en 40 μmol/l in the nutrient solution. Next to these preventive treatments were conducted with the elicitors/green plant protection products Hicure, SilicaPower and Inssimo. A concentration of 10 μmol/l Mn had a preventive effect against powdery mildew in sweet pepper and rose in contrast to gerbera and kalanchoe. Treatment with Inssimo had a preventive effect on powdery mildew in all plant-mildew systems. Combinations of Mn treatments with Inssimo did not lead to synergistic effects. To maximise the use of Inssimo for plant resilience treatment should be coupled to an early warning system which indicates on time whether preventive treatment is necessary.