ENTOMOPATHOGENIC FUNGI ASSOCIATED WITH IXODES-RICINUS TICKS

The objective of this study was to demonstrate the occurrence of entom opathogenic fungi on Ixodes ricinus ticks in relation to the tick stag e, engorgement and season. Ticks were collected from the vegetation, f rom small rodents and from deer. All entomopathogenic fungi found belo nged to the Hyphomycetes. Paecilomyces farinosus and Verticillium leca nii were the predominant species. Other species, found only on engorge d females were: Beauveria bassiana, B. brongniartii, P. fumosoroseus a nd V. araneanrm. Eight out of 1833 ticks collected from the vegetation and three out of 269 engorged nymphs were infected with fungi. Thirty -three out of 149 engorged females were infected, whereas males and en gorged larvae were not infected. Throughout the season, a significantl y higher proportion of ticks collected in autumn were infected. Entomo pathogenic fungi may have a significant impact on the size of the I. r icinus population, since females were the most frequently infected sta ge.