As insect resistance to phosphine continues to climb across both on-farm and bulk storage, growers face a constant challenge: how to slow resistance while protecting grain quality and market access. Recent GRDC-supported resistance monitoring shows a slight dip in strong phosphine resistance this year, but the overall national trend remains upward, with about 30 per cent of pests now showing strong resistance—well above the 10–15 per cent level considered manageable.
Continue readingPhosphine Best Management Practices: Disinfesting stored commodities
Phosphine remains the most widely used fumigant in Australia’s grain industry due to its effectiveness, low cost, and residue-free status. However, increasing resistance among key insect pests highlights the need for strict adherence to best practice guidelines.
This comprehensive manual outlines:
1. Proper application methods across different storage types (silos, bunkers, sheds)
2. Critical factors such as gas concentration, exposure time, temperature, and moisture
3. Equipment for monitoring gas levels and ensuring safe fumigant handling
4. Strategies to delay and manage resistance, including use of sulfuryl fluoride and integrated pest management
Compiled by leading experts including Dr Manoj Nayak, Dr Joanne Holloway, Chris Warrick, and Patrick Wilson, this document is a valuable resource for growers, storage operators, and advisors working to maintain grain quality and market access.
Continue readingInsect Control and Effective Fumigation Help Guard Your Harvest
Protecting your harvest from insect threats requires diligent control and precise fumigation practices. In GRDC’s article, Insect Control and Effective Fumigation Help Guard Your Harvest, the focus is on strategies to enhance biosecurity and preserve grain quality. Key points include:
Fumigation Best Practices: Effective fumigation techniques are critical for eliminating pests while safeguarding the crop.
Biosecurity Measures: A strong biosecurity approach helps prevent insect infestations before they become a threat.
Integrated Pest Management: Using a combination of methods, including proper storage and sanitation, can minimize pest risks.
Stay informed on the best methods to protect your harvest and ensure grain quality
Pest Resistance Raising the Knowledge Bar for Stored Grain
Over the past five years, insect pests have become harder to control with the fumigant used widely in on-farm storage, the GRDC’s national monitoring and management program has found.
Continue readingGRDC Grains Research Update, Online – Grain Storage update for the Western Region
Aeration, Back Pressure, fan performance, field testing, Fumigation, phosphine, Resistance, update, Venting, webinar
Continue readingGRDC Grains Research Update Online – Grain storage update for the Northern & Southern regions
GRDC Grains Research Update, Online – Grain Storage update for the Western Region. Including topics – Aeration, Back Pressure, Fan performance, Field testing, Fumigation, Phosphine Resistance, Venting.
Continue readingHow good are stored grain protectants?
Resistance monitoring of key insect pests has shown that combined grain protectants are a valuable integrated pest management tool for stored grain.
Up to 30 per cent of freshly harvested grain is treated with contact insecticides – or grain protectants – before being placed into storage.
Continue readingSulfuryl fluoride can break phosphine resistance
Key points
– Rotating phosphine fumigation with sulfuryl fluoride will protect against the development of phosphine resistance
– Sulfuryl fluoride can only be purchased and applied by licensed fumigators
Probing phosphine resistance in rusty grain beetle
Key points
– Strong resistance to phosphine in rusty grain beetle has increased substantially since the first resistant population was discovered in 2007
– The rusty grain beetle is mobile and resistant populations are present across the full spectrum of the grain supply chain
– Area-wide integrated pest and resistance management has the potential to suppress this problematic species indefinitely
Users must heed rising phosphine resistance
Key points
– Strong resistance to phosphine in stored grain insects has both increased and spread over the past decade, with more detections in eastern Australia than Western Australia
– Misuse of phosphine, particularly in unsealed storages, appears to be the main reason for the development of strong resistance










