The purpose of this study was to determine the effect of the entomopathogenic fungus Metarhizium sp. on spore quality and mortality rate in Oryctes rhinoceros L larvae. This research was carried out in the protection laboratory of the Marihat Oil Palm Research Center, Pematang Siantar for 5 months starting from October 2021 - February 2022. Laboratory research using a non-factorial Completely …