STUDIES ON THE FIELD PERFORMANCE OF METARHIZIUMANISOPLIAE V AR. ACRIDUM (GREEN MUSCLE®) AGAINST MIXED POPULATIONS Of' GRASSHOPPER IN ETHIOPIA

Abstract

Two consecutive field studies were carried out on the performance of Metarhizium
anisopliae var. acridum against mixed grasshopper species under field conditions in North East of
Ethiopia during the 2003 cropping season. Both the entomopathogen and 'control (gasoline) were
applied against the experimental grasshoppers using a handheld, battery operated VLV+ sprayer. Each
treatment was aSSigned randomly. In both trials, the fungus killed more grasshoppers than the control.
The mortality of grasshoppers treated with Green MuscIe® per day ranged from 0 to 19.78 % in the first
trial and 20 to 70.91 % in the second triaL Only 0 to 8.7% and 7.79 to 35.78% of insects in the control were
dead, respectively. About 37.91 % and 37.71 % of the grasshoppers died from the fungus treated plots
showed external sporulation of conidia following incubation in the first and second trials, respectively,
confirming that death was due to mycosis. The fungus was found to be target specific as none of the
non-targets showed sign of infection/fungal external sporulation following routine checkups on
cadavers. The present result conform with those findings elsewhere that Green Muscle® can cause
infection which could be sufficient to suppress grasshopper populations below that which could cause
economic injury level when applied under field conditions in a similar way as chemical pesticides.