Control of Phaulacridium vittatum (Sjöstedt) (Orthoptera: Acrididae) in Field Cages using an Oil‐based Spray of Metarhizium flavoviride Gams and Rozsypal (Deuteromycetina: Hyphomycetes)

Abstract

Conidia of an isolate of Metarhizium flavoviride, F1985 suspended in oil were sprayed onto mainly adult Phaulacridium vittatum (Sjöstedt) in field cages at two dose rates: 2 × 109 and 2 × 108 conodia/mL. Both rates were effective in killing all P. vittatum in the cages in 3 weeks, under the prevailing cool conditions. Samples of grasshoppers taken from the treated cages at 4, 8 and 14 d post‐spraying died within 1–6 d when placed at constant 26°C in the laboratory. Samples of foliage fed to healthy grasshoppers showed that some infections conidia persisted for 14 d. the results indicate that it may be possible to control P. vittatum with an oil‐based spray of conidia of M. flavoviride. Copyright © 1994, Wiley Blackwell. All rights reserved