Apple scab (V. inaequalis) is the main disease in organic apple production. Availability of varieties is a major problem as only a few robust varieties are available on the market.

The researchers propose a list of currently well-known robust varieties that are suitable for large scale production. Current breeding of new cultivars is crucial for the future of organic growing, stay tuned.

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.

A collection of abstracts from the Fourth International Symposium on Biological Control of Bacterial Plant Diseases.