The entomopathogenic fungus Beauveria bassiana used as granules has no impact on the soil-dwelling predatory mite Stratiolaelaps scimitus

Frankliniella occidentalis (Pergande) is an economically important pest worldwide and has demonstrated a particularly difficult to manage. Controlling soil-pupating thrips is a promising strategy for controlling F. occidentalis. Beauveria bassiana granules and soil inhabiting predatory mite Stratiolaelaps scimitus have been proposed as alternative control agents. This study evaluated the effect of the B. bassiana conidia on the survival, immature development, longevity, reproduction of S. scimitus by laboratory bioassays. The effect of B. bassiana used as granules on survival of S. scimitus was also assessed under potted condition. When B. bassiana was sprayed directly on each immature stage of S. scimitus at a concentration of 1 x10(7) ml(-1) conidia, their survival rates and developmental times were not affected. Direct spray of B. bassiana on female S. scimitus did not affect their reproduction and longevity. The potted test showed that B. bassiana used as granules has no impact on the density of S. scimitus. Our study suggested that using B. bassiana granules is compatible with release of S. scimitus in soil, and their combined use may be an alternative to traditional F. occidentalis management.