In organic farming, disease control is based primarily on preventive measures such as crop rotation and the cultivation of less susceptible varieties. However, economic factors such as the market and labour resources are in contradiction with such preventive measures. Consequently, direct control measures may also be necessary in organic agriculture to ensure satisfactory yields and high-quality produce.
An example of a dangerous pathogen in organic arable farming is common wheat bunt. Wheat infested with this fungal disease is contaminated with toxins and cannot be used as food or feed. By using healthy or dressed seed, the disease can be largely prevented. Since disease-free, resistant seeds are not always successfully produced in organic farming, we are currently developing a bio-compatible seed-dressing product based on natural substances. The focus here is on products from plants with fungus-inhibiting properties. We examine their effect in vitro on the germination and growth of the pathogen. Subsequently, we test the disease-suppressive effect of the most promising plant products on wheat in climate chamber and field trials. In order to optimise efficacy, we also investigate suitable formulation and application techniques.
We are using the same approach to develop a seed-dressing agent for controlling snow mould, a disease which can cause major crop losses in organic grain farming. In order to ensure high-quality, mycotoxin-free organic cereals, we are also developing plant products to control Fusarium diseases in wheat. Owing to changed cropping systems, Fusarium fungi have obtained high attention over the last few years. This, coupled with the toxigenicity of the fungi, has made them the focus of much attention. To enable the replacement of copper fungicides in organic potato production, we also examine the effects of our plant products on the control of late blight of potato. In addition, we are optimising our late potato blight forecasting system PhytoPRE, to help organic farmers apply copper fungicides effectively and in low doses.
Effect of extracts and plant products on the germination of Fusarium graminearum conidiospores