Wirkung entomopathogener Pilze gegen die Kirschfruchtfliege Rhagoletis cerasi.

Summary

Susceptibility of different life stages of Rhagoletis cerasi to entomopathogenic fungi. The effects of six fungus strains (Deuteromycotina: Hyphomycetes) on the mortality of different life stages of the European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae), were assessed in a series of laboratory experiments. All fungus strains caused mycoses in larvae and adults of R. cerasi. Virulence however varied considerably between the strains. Effects on L3-larvae were negligible; none of the fungus strains caused mortalities of more than 25% of larvae. Adults by contrast were highly susceptible to fungal infection. Beauveria bassiana and Paecilomyces fumosoroseus caused 90 to 100% mortality and had a strong influence on fecundity. Metarhizium anisopliae also showed reliable effects. The pathogenicity of Paecilomyces farinosus was low. Higher conidia concentrations lead to higher mortality, whereas B. bassiana was most efficient at low concentrations. Young flies showed lower mortality rates than older flies but, sub-lethal effects on eclosion rate of eggs were greater in young than in older flies.