NOSEMATIDAE AND OTHER PROTOZOA AS AGENTS FOR CONTROL OF GRASSHOPPERS AND LOCUSTS: CURRENT STATUS AND PROSPECTS

Abstract

AbstractProtozoa known to infect Acrididae include certain Amoebida (Phylum Rhizopoda), Eugregarinida, Neogregarinida (Phylum Apicomplexa) and at least one species from the Phylum Ciliophora, but are mainly Microsporida (Phylum Microspora). Among the Microsporida,Nosema locustaeCanning has been the most common subject of large-scale field testing as a potential microbial control of grasshoppers and locusts. Although there have been demonstrations of significant impacts of Protozoa such asNosemaspp. on survival, development, reproduction and feeding of grasshoppers and locusts, these candidates have not met the requirements for fast-acting control of Acrididae. However, recently discovered and as yet undiscovered Microspora and other Protozoa may offer reliable non-chemical control of grasshoppers and locusts. Research on candidates such asNosema locustaehas not been wasted effort; at a minimum, research invested toward development of methods of formulation, application, assessment and ecological fate of these potential microbial control agents has provided useful information needed to prepare for the eventuality of discovery of more fast-acting protozoa, and has contributed to development of field methods required for testing of other microbial agents. With improvements in understanding of insect behavioral and physiological responses, satisfactory short-term efficacy (perhaps resulting from combined formulations with behavioral modifiers or stressors) may allowN.locustae,N.cuneatumHenry,N.acridophagusHenry orJohenrea locustaeLange et al. to also serve a role in limiting acridid abundance and activity, either as an agent of biological control in sites requiring special care, or within a rangeland IPM context.