Australia’s reputation as a supplier of high quality, clean grain can quickly be destroyed due to contamination of grain with either live or dead insects. Individual loads of contaminated grain can be deemed unmarketable and rejected by customers causing temporary loss. But this can also lead to the longer loss of access to both local and export markets.
Insecticides, including fumigants, grain protectants and storage treatments, are key components of grain insect pest management systems. Although grain storage managers routinely use non-chemical control methods including hygiene, and grain cooling and drying, in many situations these are not sufficiently effective to maintain grain at the standard required by markets. Effective residual control of grain storage pests can be achieved and maintained through judicious use of grain protectants.
Grain protectants have been used by the Australian grain industry since the 1960s. Unlike fumigants, protectants are designed to provide up to 9 months protection, and are intended to protect un-infested grain, not to treat infested grain. Currently there are only six registered protectant compounds available for use in Australia. These include the organophosphates fenitrothion, chlorpyrifos-methyl and pirimiphos-methyl, the pyrethroid deltamethrin, spinosad, and the insect growth regulator S-methoprene. None of these compounds can control the full spectrum of major pests at registered rates either because of resistance or because of poor efficacy. Therefore, they are applied as mixtures. Resistance occurs in several of the major pest species to one or more protectants. The lesser grain borer, Rhyzopertha dominica, is the most difficult to control and several protectants have been specifically developed to manage this pest.
The following mixtures are recommended for complete control of all major pest species. Deltamethrin-based products should be alternated every one or two years with non-deltamethrin-based products.
Deltamethrin (+ piperonyl butoxide) + S-methoprene + EITHER fenitrothion OR chlorpyrifos-methyl OR pirimiphos-methyl
OR
Deltamethrin (+ piperonyl butoxide) + EITHER fenitrothion OR chlorpyrifos-methyl OR pirimiphos-methyl
OR
Spinosad + S-methoprene + EITHER fenitrothion OR chlorpyrifos-methyl OR pirimiphos-methyl
METHOGRAIN Delta IGR Grain Protectant contains deltamethrin (+ PBO) + S-methoprene in a single formulation and is also marketed as METHOGRAIN Delta IGR Grain Protection Pack in combination with METHOGRAIN Fenitrothion for convenient dosage and use.
Pest control in grain storage
Check the possible infestation of your grain regularly.
Always check for mould.
Regularly check the facilities and outer spaces against rodents (rats and mice). In case of infestation use the most appropriate rodenticide and baiting stations. Never leave rodenticides uncovered, spoiled or in open spaces without a proper, lockable, child proof baiting station.
Treatment of grain storage facilities, equipments, structural cereal grain storage on farm, produce stores, feed and flourmills, warehouses and processing plants, transport equipment, animal feed bins:
Methograin Fenitrothion 1000
10 mL/L water (1 L dilute spray treats approx 20 m2 of walls and floors surface.) Apply diluted spray to walls, floors, roof, structure, machinery, transport vehicles and areas around storage facilities. This treatment should be used as a routine hygienic procedure before grain is stored in any facility. Precautions should be taken to prevent surface contamination of grain. Treatment should not be repeated more frequently than at 2 monthly intervals in warm weather and 3 monthly intervals in winter months.