The spectrum and occurrence of entomopathogenic fungi in soils from apple orchards

Abstract

The spectrum and occurrence of entomopathogenic fungi in orchard soil and arable soil were evaluated using an "insect bait method". Soil samples taken in autumn and spring from sward, herbicides fallow and arable soil were baited with <i>Galleria mellonella</i> larvae. Entomopathogenic fungi <i>Beauveria bassiana</i> (Bals.) Vuill., <i>Metarhizium anisopliae</i> (Metsch.) Sorok. and <i>Paecilomyces fumosoroseus</i> (Wize) Brown et Smith were isolated from three species of orchards soil and adjacent arable soil. Infection levels of <i>G. mellonella</i> larvae were depended from species of soil . <i>M. anisoopliae</i> caused most frequent infections of bait insects in light loamy sand and <i>P. fumosoroseus</i> in alluvial silt and coarse sand. <i>B. bassiana</i> was dominated in alluvial silt. It was established that <i>M. anisopliae</i> and <i>B. bassiana</i> infected more larvae in autumn than in spring. In case of <i>P. fumosoroseus</i> an opposite tendency was observed. Generaly in arable soil and sward number of infected larvae was higher than other stands. In case of light loamy sand more infections of <i>G. mellonella</i> larvae were found in samples from herbicides fallow. Irrespective of soil type <i>B. bassiana</i> was the dominated species isolated from herbicides fallow, <i>M. anisopliae</i> from sward and <i>P. fumosoroseus</i> - from arable soil.