POTENTIAL OF ENTOMOPHAGA MAIMAIGA HUMBER, SHIMAZU AND SOPER (ENTOMOPHTHORALES) FOR SUPPRESSING LYMANTRIA DISPAR (LINNAEUS) OUTBREAKS IN BULGARIA

The Asian fungal entomopathogen Entomophaga maimaigawas first introduced in Bulgaria for biological control of gypsy moth, Lymantria dispar, in 1999 and the first epizooticsin gypsy moth populations were observed in 2005. Six introductions of E. maimaiga in oak forests with heavy L. disparinfestations were conducted from 2008 to 2011 in different regions of the country, including Nova Zagora, Gorna Oryahovitsa, Popovo, Targovishte and Staro Oryahovo. As a result of these introductions, host density was decreased by 55.1–100% and the outbreaks were suppressed. After the introduction of the pathogen in Bulgaria, no microbiological or chemical control of L. disparhas been necessary and the last two gradationshave been estimated to be 15–30% of the values in previous gradations.