<p class="MDPI12title">Entomopathogenic fungi, Hirsutella thompsonii F.E. Fisher Safe Mycoacaricide for the Management of Coconut Mite, <span style="color: windowtext;">Aceria guerreronis</span><span style="color: windowtext;"&gt

Aceria guerreronis Keifer (Acari: Eriophyidae) is a phytophagous mite that is one of the serious pests of coconut fruits worldwide. Chemical controls have been and continue to be the primary means of control. Because pesticide compatibility with natural enemies is a major concern for IPM systems. The aim of this study was to explore the contact toxicity and egg hatching inhibition of conidia suspension and crude ethyl acetate extract of Hirsutella thompsonii F.E. Fisher against adults and eggs of A. guerreronis Keifer. The results indicated that six isolates of H. thompsonii F.E. Fisher were evaluated for their pathogenicity against eggs and adults of the coconut mite (A. guerreronis Keifer), and H. thompsonii F.E. Fisher TBRC 6805 and TBRC 6933 resulted in the highest mortality (100%) on the 3rd day post-inoculation (DPI). The crude ethyl acetate extracts 5% (w/v) of H. thompsonii F.E. Fisher isolates TBRC-BCC 13865 showed the highest mortality to eggs (92%) and adults (98%) of A. guerreronis Keifer, and the LC50 value was 2.629% (eggs) and 1.704% (adults) after 72 h posttreatment. This study shows that H. thompsonii F.E. Fisher, a fungus well known for controlling biotic stress brought on by insect pests, can also have potential for the development of novel bioacaricides to control A. guerreronis Keifer in an integrated pest management program.