Efficacy of Beauveria bassiana and Cordyceps javanica mycoinsecticides against spotted lanternflies, Lycorma delicatula, in laboratory bioassays

Abstract

ABSTRACT The invasive spotted lanternfly, Lycorma delicatula (White), was first detected in southeastern Pennsylvania in 2014 and has since expanded its range to ten more states. Since fall 2017, we have found L. delicatula killed by Beauveria bassiana in multiple counties in southeastern Pennsylvania. Mycoinsecticides containing strains of entomopathogenic fungi are commercialised worldwide and could be a tool for managing L. delicatula populations. In 2020 we conducted laboratory bioassays on L. delicatula using five mycoinsecticides, including four strains of B. bassiana and one strain of Cordyceps javanica. Mycoinsecticides were directly applied to all L. delicatula nymphal instars and adults at three different stages of reproductive maturity. All B. bassiana mycoinsecticides were effective at killing L. delicatula under optimal conditions in the laboratory. Lycorma delicatula nymphs exposed to B. bassiana mycoinsecticides displayed mean survival times of 6.3–6.9 days and 90–93% mortality after 14 days, and adults displayed mean survival times of 7.2–9.8 days with 82–99% mortality after 14 days. PFR-97 killed L. delicatula at a slower rate than all B. bassiana mycoinsecticides tested with 43–57% mortality after 14 days. Adult L. delicatula males died significantly faster than females for all treatments except BioCeres.