The effect of combined and separate applications of <i>Cordyceps fumosorosea</i> and <i>Phytoseiulus persimilis</i> on the biological control of <i>Tetranychus urticae</i> under laboratory and field conditions

This study investigated the effect of combined and separate applications of the entomopathogenic fungus (EPF), Cordyceps fumosorosea (Hypocreales: Cordycipitaceae), and the predatory mite (PM), Phytoseiulus persimilis (Acari: Phytoseiidae), on the biological control of Tetranychus urticae (Acari: Tetranychidae) in field-grown tomatoes in Northwest T & uuml;rkiye in 2021. Based on the laboratory tests, it was determined that C. fumosorosea caused moderate mortality on T. urticae and relatively low mortality on P. persimilis. Field tests on tomatoes showed that the most effective result in suppressing the populations of T. urticae was by the release of P. persimilis alone, followed by the combined application of C. fumosorosea and P. persimilis. The application of C. fumosorosea alone showed a very low effect on the populations of T. urticae. Our results suggest that releasing P. persimilis alone provides more effective biological control of T. urticae on field-grown tomatoes than the combined application of C. fumosorosea and P. persimilis, and application of C. fumosorosea alone.