The Australian Dept of Agriculture, Fisheries and Forestry is predicting a near record wheat harvest in 2022–23.
Wheat production is forecast to reach 32.2 million tonnes which is 30% above the 10-year average of 24.7 million tonnes. If realised, this will be the second-highest national wheat harvest on record.
The high volume of grain being produced will stretch conventional silo-based grain storage infrastructure across the country and will mean an increase in reliance on bunkers, bags and sheds as storage options.
Many of these options are not able to be sealed which won’t allow use of fumigants such as phosphene and sulfuryl fluoride to eliminate stored product pests.
In this instance the use of a grain protectant insecticide is a valuable tool to manage the key stored grain pests of cereals in both sealed and unsealed grain storage, says Ed Bracey, rural business specialist at Envu (formerly Bayer’s Environmental Science Professional business).
“An application of K-Obiol EC Combi mixed with an approved organophosphate insecticide such as Chlorpyrifos methyl or Fenitrothion can provide up to 9-months’ protection from the four major stored cereal grain pests in Australia.”
Envu’s decision chart can be used to select an appropriate product combination. Mr Bracey said K-Obiol is not an irradicant and should be applied to insect free grain as it is transferred into the storage.
Grain protectant products in Australia are subject to strict use guidelines which include a product stewardship program. This is to ensure that the products are used correctly in a manner that is safe to those applying the product and for consumers of the treated grain.
“It is critical that grain treated with protectants is declared with vendor declarations so that grain processors can make informed decisions about the use of the grain and any future treatments applied,” Mr Bracey said.
“The stewardship training also helps manage insecticide resistance which can occur if products are not used correctly. There are some key components to managing insecticide resistance management in stored grain.
1. Always mix an organophospate with K-Obiol to provide broad spectrum protection
2. Alternate between chemical groups every year or two. That is between Conserve and K-Obiol
3. Only use fumigants in sealed systems where a sufficient concentration of fumigant can be maintained to control all the insect pests present. Poorly sealed storage can lead to underdosing and resistance development
4. Maintain good hygiene and remove any waste grain that may harbour pests in and around storages and machinery
5. Use a non-chemical control such as diatomaceous earth as a barrier treatment
6. Use aeration and temperature management to reduce insect breeding. Most stored grain pests stop reproduction at 18 degrees C or less.
Mr Bracey said the K-Obiol stewardship has been simplified recently so first-time users simply have to watch a training video and sign a declaration form which can be done at the point of purchase. There is a training course which can then be accessed at their leisure.
