Fungi are among the most important microbial pathogens of grasshoppers
with potential for development as biological control agents. Unlike m
ost other insect pathogens that must be ingested to initiate disease,
fungi generally invade insects via the external cuticle. The most comm
on fungi that are pathogenic to grasshoppers are Beauveria bassiana, M
etarhizium anisopliae, Metarhizium flavoviride, Sorosporella sp., and
fungi in the Entomophaga grylli complex. A review of the latest inform
ation on the development of these fungi as microbial control agents of
grasshoppers is presented. Species in the E, grylli complex are being
used in classical biocontrol. This has resulted in controversy as the
re are indigenous nonpest grasshopper species that may be affected thr
ough introduction of the nonindigenous fungal strains. Beauveria bassi
ana and M, flavoviride are being developed for inundative control. The
se fungi can be mass produced and applied with equipment used for conv
entional pesticides. Conidia are applied either at ultralow volume in
oil, as oil emulsions, or as bran-bait formulations. Field trials in A
frica and North America have demonstrated significant grasshopper redu
ctions. Improvements in formulation and inoculum targeting may further
improve their efficacy.