Pathogenicity of selected strains of entomopathogenic fungi to tetranychid mites (Tetranychidae) under laboratory conditions

摘要

The aim of the laboratory experiments was to assess the pathogenicity of selected strains of entomopathogenic fungi in relation to the two-spotted spider mite (Tetranychus urticae) and raspberry spider mite (Neotetranychus rubi). The tested fungal isolates, applied in the form of spraying with an aqueous spore suspension (1 x 105/ml), were characterized by varying pathogenicity in relation to the mobile forms of spider mites. The highest mortality rate of pest was caused by Lecanicillium lecanii (75.4%) and Beauveria bassiana (69.1%) isolates. The lowest mortality of T. urticae was recorded when Isaria fumosorosea and Metarhizium flavoviride were applied. Increased concentration of fungal spores in the aqueous suspension from 1 x 107ml to 1 x 107/ml did not significantly increase the number of infected individuals. Entomopathogenic fungus L. lecanii caused over 75% mortality of the raspberry spider mite.