FORMULATION OF GRASSHOPPER AND LOCUST ENTOMOPATHOGENS IN BAITS USING STARCH EXTRUSION TECHNOLOGY

Starch extrusion technology was used to produce carriers for 'contact baits' that utilise aspects of feeding (or other) behaviour for the pu rpose of attraction and stimulation of grasshoppers and locusts and ac hieve uptake of the active ingredient by contact rather than ingestion . A rapid, continuous and efficient production of bait carrier was ach ieved using a co-rotating, twin-screw food extruder. Extrusion conditi ons were adjusted to produce a rigid, hard and highly expanded maize-s tarch extrudate, and laboratory bioassay demonstrated a high degree of acceptance of maize-starch baits by Schistocerca gregaria. Bait formu lations that achieve dose transfer by contact rather than ingestion ma y be particularly appropriate for the formulation of fungal entomopath ogens that infect by contact rather than ingestion.