Laboratory Trials of Metarhizium anisopliae var. acridum (Green Muscle®) Against the Saxaul Locust, Dericorys albidula Serville (Orthoptera: Dericorythidae)

Mode of Infection of Metarhizium spp. Fungus and Their Potential as Biological Control Agents

“…Previous studies have found that M. acridum has an insecticidal effect against locusts and grasshoppers, which are the main agricultural pests. M. acridum is currently used as a biological control agent in Mexico, Africa, and Australia for the control of locusts and grasshoppers [ 5 , 7 , 108 ]. Commercial biopesticides using M. acridum as an active ingredient have been developed in both Africa and Australia, known as GreenMuscle ® and GreenGuard ® , respectively, to act as control agents against locusts and grasshoppers [ 7 , 108 ].…”

“…GreenMuscle ® has been recommended by FAO and has obtained registration for its usage. However, few people have used GreenMuscle ® due to its slow mode of infection, high costs, temperature dependency, and the instability of the formulation developed [ 108 ].…”

“…Factors that affect the efficacy of M. acridum are the timing of the application of conidia, the temperature during the infection of M. acridum , the strain of the M. acridum used, the medium that is used to culture M. acridum , and the method of application of the conidia [ 5 , 7 , 12 , 83 , 108 ].…”

“…For the timing factor, it was found that younger nymphal instar of locusts are more susceptible than older nymphal instars. It was observed that 10 10 spores mL −1 caused higher mortality for 3rd nymphal instars compared to 5th nymphal instars 15 days post-inoculation in 2005, but not in 2006 [ 108 ]. Klass et al [ 109 ] also suggested that for the successful control of locusts, it is better to target early nymphal instars to prevent later nymphal instars from developing into adults which could reproduce and expand the locust population.…”