DIACONT - Alternative methods of protection of maize from Western Corn Rootworm (diabrotica virgifera virgifera)

The aim of this project is to demonstrate the efficacy of 4 antagonistic organisms in controlling Western Cornrootworm (WCR) larvae or protecting corn roots. This should enable farmers to use 4 different biological methods and thereby decreasing dependency to only one active ingredient (Cypermethrin) in WCR control. Furthermore it is aimed to stimulate self-regulation of WCR by yearly prophylactic application of small doses of these antagonistic organisms to the field. For Dianem (Heterorhabditis bacteriophora) which is already registered in Austria the efficacy of practical applications by farmers shall be correlated with agronomical and environmental factors in order to find out what promotes successful application and what prevents it. For GranMet (Metarhizium brunneum) field trials shall demonstrate the efficacy which has been shown in the laboratory very clearly. Concerning Lecanicillium lecanii the mode of action in the soil has to be studied in detail as Diabrotica eggs were infected frequently by these fungi in the laboratory. Outdoor microplot trials will give information of application details for further field trials. Concerning SPA69 (Stenotrophomonas rhizophila) a protecting agent for corn roots will be examined in field trials. Overall the application of combinations of these organisms under investigation will be performed in the last year. The results are dependent on the progress of these experiments. In best case it will enable the registration of new plant protection products or improvement of advice on existing products. The overall aim would be the stimulation of self-regulation of WCR by yearly application of smaller doses of these naturally occurring antagonistic organisms.