Laboratory Beauveria bassiana (Bals.) Vuill. bioassays on spruce bark beetle (Ips typographus L.)

Abstract: The massive damages caused by Ips typographus in spruce forests in Romania, thesevere restrictions on the use of chemical insecticides, the identification of natural Beauveriabassiana outbreaks in the Romanian forests infested with bark beetle and the isolation of a newB. bassiana strain, led to the development of some researches on the possibility to use thisentomopathogenic fungi for reducing the damage caused by bark beetles. In laboratoryconditions, the susceptibility of I. typographus to infection by a naturally occurring B. bassianastrain was tested. Utilization of a B. bassiana conidial suspension (3.31 x 1011 conidia ml-1)induced beetle mortality, length of mother galleries reduction and larval galleries numberreduction.