BIOLOGICAL CONTROL OF Melolontha melolontha L. LARVAE WITH ENTOMOPATHOGENIC BIOINSECTICIDE BASED ON Beauveria brongniartii

From 2010 to 2013 tests were conducted with entomopathogenic bioproduct based on Beauveria brongniartii, in nurseries of the Botosani, Neamt and Suceava Forest Departments. At RDPP Bucharest a technology for multiplication on nutrtive solid substrate of entomopathogenic fungus B. brongniartii was developed, on the basis of which the experimental bioinsecticide BioMelCon (G) was obtained. Soil treatments were performed with the BioMelCon (G) in doses ranging from 100 to200 kg/ha. The tested dosages were achieved by applying two treatments per year. Application of biological product held generally early spring on surfaces free from crops, to ensure a uniform distribution and to create the possibility of periodic inspection of the treatment effect by soil surveys. Checking the effectiveness of treatment was carried out in several stages, in different site conditions. The paper presents results concerning the effect of applying several biological treatments on Melolontha melolontha larvae (L2-L3). The cumulative effect of the biological product and the agricultural practices of experimental fields have led to a decreased density of larval populations under economic threshold level.