Investment

GRDC Code: DAQ2209-001RTX

National resistance monitoring and management of stored grain pests

Australian growers rely heavily on phosphine fumigation to disinfest stored grain and meet market expectations for high-quality grain with adherence to 'nil tolerance' for live insects. The key to the sustainable use of this cheapest and residue-free treatment has been the successful management of resistance in major pest species over the years. In addition, many growers outside of Western Australia use grain protectants enabling long-term protection of grain from major pests during storage.

Phosphine resistance contributes to fumigation failures whereas resistance to grain protectants makes them ineffective. Resistance monitoring has underpinned the research that has enabled the sustainable use of phosphine and grain protectants and has also provided a basis for a significant part of the extension messages to growers. The heavy demand on phosphine nationally, and growing demand for alternative treatments such as sulfuryl fluoride and spinosad in eastern Australia, means that resistance to new treatments could have developed in some pests. Such scenarios will have a greater impact on growers in maintaining the 'nil tolerance' level, whenever they choose to sell their grain.

Fumigant or grain protectant resistance has the potential to reduce grower profitability because of costs incurred after harvest. The use of ineffective treatments (through either underdosing or development of resistance in key pest species) will result in rejections and costs of retreatment or possible downgrading once live insects are detected.

The value of a national resistance monitoring program to the Australian grains industry include:
* Growers and bulk handlers benefit through efficiencies that reduce insect control failures and manage resistance through timely eradication of resistant populations (based on an understanding of strength, frequencies, and spread of resistance)
* Help maintain Australia's market access for premium quality grain

Project start date:

28/09/2022

Project end date:

31/08/2025

Crop type: