THE COMBINED EFFECTS OF THE FUNGUS METARHIZIUM FLAVOVIRIDE GAMS AND ROZSYPAL AND THE INSECTICIDE CYPERMETHRIN ON LOCUSTA-MIGRATORIA MIGRATORIOIDES (REICHE AND FAIRMAIRE) IN THE LABORATORY

A problem in the use of the fungus Metarhizium flavoviride Gams & Rozs ypal to control locusts is that the locust continues eating for the fi rst few days after the fungus has been applied. Applying a dose of 13 000 spores per locust to adult Locusta migratoria migratorioides (Reic he & Fairmaire) in 10 ppm cypermethrin (approximately LC(10), even 7 d ays after dosing) inhibited feeding by 50% on day 1 after treatment an d advanced the onset of locust mortality from the fungus by 48 h. A si milar inhibition of feeding from the cypermethrin also occurred in com bination with doses of fungus as low as 375 spores per locust, but the earlier locust mortality was not then observed. It was also determine d that cypermethrin was not toxic to M. flavoviride in in vitro tests.