News

By Jordan Scott, Grains Biosecurity Officer, South Australia

Accurate and timely diagnosis of crop pests and diseases starts well before a sample reaches the laboratory. Every step, from collection to packaging and transport, plays a vital role in ensuring reliable results. With Australia’s increasing focus on strengthening defences against exotic threats such as Karnal bunt (Tilletia indica), careful sample handling has never been more important.

The quality of specimens submitted, directly influences a laboratory’s ability to deliver conclusive results and how quickly biosecurity agencies can respond to prevent further spread. Submitting well-preserved samples, accompanied by accurate information and proper handling, is essential to protecting Australia’s primary industries.

Why submitting quality samples matters

Laboratories such as the South Australian Research and Development Institute (SARDI) and equivalent state diagnostic services rely on high‑quality, well‑labelled samples for accurate pest and disease identification. Well-prepared samples do not only support routine diagnostics but are essential for detecting exotic threats that could compromise market access. Poor handling can degrade material, hamper accurate diagnosis and, in some cases, increase the risk of spreading the pest or disease.

Submitting samples: common pitfalls and best practice

Getting sample submission right is vital for accurate diagnostic results and strong biosecurity outcomes. Avoid these frequent mistakes and follow recommended steps for any type of specimen (plant material, pest, or disease):

• Preserve samples correctly: Avoid sending dried out, rotten, or poorly protected specimens. Preservation needs may differ depending on the pest, disease, or insect stage. If unsure, contact your local biosecurity or diagnostic agency before collecting.
• Use suitable packaging: Choose sturdy, leak-proof containers. For plant diseases, use clean paper bags to prevent condensation and rot; double-bag samples in a second paper or sealable plastic bag to contain spills and reduce cross-contamination.
• Provide clear information: Always include key details with your sample, including:
  • location and date of collection
  • crop type, variety or host plant
  • symptoms and description of the issue (clear photos can greatly assist accurate diagnosis and can often be sent separately via email to the lab or to a biosecurity officer)
  • your contact details
  • the desired diagnostic outcome (for example, identification, confirmation).
• Label samples properly: Mark each sample clearly, package multiple samples separately and use waterproof labels.
• Minimise biosecurity risks: For suspected exotic or quarantinable pests such as Karnal bunt or Khapra beetle, cordon off the site and avoid sending live specimens unless requested. Agronomists collect samples where possible, ensuring they are double-bagged and that appropriate protective measures such as gloves and coveralls are used.
• Keep samples cool and dry: Do not expose samples to heat or moisture during storage and transport, as this may compromise diagnostics.
• Submit promptly: The faster the samples reach the diagnostic facility, the higher the quality and usefulness of the test results.
• Get advice if unsure: Contact your local Grains Biosecurity Officer (GBO) for guidance before collecting or submitting any suspect material.

Cereal rust survey 
Growers also have an opportunity to contribute to the Australian Cereal Rust Survey. This project is invested in GRDC and led by the survey team at the Plant Breeding Institute, University of Sydney.

Cereal rusts can cause significant crop damage and remain a serious problem for growers across Australia. That’s why the University of Sydney conducts an annual survey to track these pathogens and it is calling on growers for support.

If you have seen rust in your wheat, barley or oats (orange, yellow or brown spots on leaves or stems), send in a sample. It’s free, easy, and helps researchers track which rust strains are out there and how they are changing. This information will go into breeding better, more rust-resistant varieties and help guide management decisions across the country.

Why participate?

Early detection makes a huge difference. Your sample could help find a new rust strain before it spreads. Plus, you will find out what type of
rust you have so you can make more informed management decisions. You can find full instructions and request your free sample submission envelope on the University of Sydney’s website.

To submit a sample:

• collect 10 to 15 infected leaves
• place them in the paper envelope provided (do not use plastic)
• label with crop type, location and date
• send to the University of Sydney’s Plant Breeding Institute.

This is a simple way to support the whole grain-growing community. Whether you manage a large operation or monitor a few
paddocks, every sample helps strengthen Australia’s biosecurity system.

GRDC Code: UOS2207-002RTX

• Resources:
  GRDC fact sheet: How to collect a rust sample (Sep 2025)
• GRDC GroundCover: Growers given edge in rust ‘arms race’ (Mar 2025)
• GRDC GroundCover: Barley boundaries crossed (Aug 2025)

To report anything unusual, call the Exotic Plant Pest Hotline 1800 084 881.

For further information and support, contact your local GBO.

The Grains Farm Biosecurity Program is an initiative to improve the management of, and preparedness for, biosecurity risks in the grains
industry at both farm and industry levels.

Launched in 2007, it is managed by Plant Health Australia (PHA) and funded by growers through Grain Producers Australia (GPA), in partnership with the governments of New South Wales, Queensland, South Australia, Victoria and Western Australia.