Functional response, numerical response, mutual interference and switching behavior of the predatory mite Euseius scutalis (Acari: Phytoseiidae) fed on Bemisia tabaci (Hemiptera: Aleyrodidae)

Abstract

The predatory mite Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae) is known to control tetranychid mites, scale insects, and whiteflies, including Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae). This study evaluated the potential of E. scutalis for controlling B. tabaci by examining its functional response, numerical response, mutual interference, and prey switching under laboratory conditions. A Type II functional response was observed when E. scutalis was fed B. tabaci eggs, with a searching rate (a) of 0.0093 and a handling time (Th) of 11.02. The numerical response of the predator indicated no significant differences in oviposition with increasing densities of B. tabaci eggs. Additionally, the per capita searching efficiency of E. scutalis remained constant as its density increased. Negative switching behavior was observed; in all ratios of B. tabaci eggs and Tetranychus turkestani Ugarov and Nikolskii eggs, the predator consistently preferred T. turkestani eggs. These findings indicate a low preference and performance of E. scutalis when targeting B. tabaci eggs.