In recent years rapeseed has become an important and strategic crop for Bulgarian agriculture. To protect it from pests and to get steady amounts of production, a significant attention has been paid to repellents to fight pests of economic importance, such as the Pollen beetle – Meligethes aeneus F. and the Rose Chafer Beetle – Tropinota hirta Poda. They appear in large numbers during the flowering periods and this fact makes it necessary to look for alternatives to chemical repellents.
In view of this fact this research aims to test the effectiveness of three varieties of Bacillus thuringiensis: strain SD Bacillus thuringiensis ssp. kurstaki (HD-1(3a-3b) and strain 20D – Bacillus thuringiensis ssp. kenyae (H4a-c); strain 345 Bacillus thuringiensis ssp. thuringiensis (H1) – against the Pollen beetle – Meligethes aeneus and the Rose Chafer Beetle – Tropinota hirta.
Tests have been carried out in laboratory conditions and on the field at the Agricultural University – Plovdiv. Based on the results, it has been found out that strain 345 and SD Bacillus thuringiensis ssp. thuringiensis appear to be highly effective against the Pollen beetle – Meligethes aeneus and the Rose Chafer Beetle – Tropinota hirta.