Control of seed borne diseases in production of organic cereals

Summary

In production of organic seed it is important to have some control measures on seed borne diseases to avoid propagation and spread of serious diseases. Due to lack of acceptable treatment methods the only way for the moment is to discard seed lots with unacceptable infections. Experiments have been started to find new and alternative methods for controlling seed borne diseases. In spring barley the results show good effect with 5% acetic acid on leaf stripe (Pyrenophora graminea) but problems with unacceptable effects on seed germination have to be solved. The old method with hot water treatment can be used and the results indicate good results against leaf stripe using water at 55°C. The effect of hot water was enhanced by first soaking the seeds in water at 20°C. Controlling loose smut (Ustilago nuda) is more complicated and here pre treatment with soaking seeds in water at 45°C succeeded by short treatment in water at 50°C gave good results.