BASF researchers have detected Australia’s first known instance of genetic mutation affecting Group 11 fungicides.
The barley leaf samples infected by net form of net blotch (NFNB) were collected during a product trial in the Yorke Peninsula, South Australia last year. After being sent to Germany for genetic analysis, test results revealed the presence of the F129L mutation, the first known occurrence of the mutation in Australia.
Melissa Brown, technical development manager for broadacre crops at BASF Australia, said the net form of net blotch – Pyrenophora teres f.sp. teres – is currently the most damaging disease in Australian barley crops and maintaining effective control of it is a very high priority for growers.
The F129L mutation has been widely reported overseas and is known to reduce the effectiveness of Group 11 fungicides, which are classified as quinone outside inhibitors (QoIs), on barley net blotch.
The leaf samples were collected in October 2022 from a trial conducted by AgXtra, an independent contract research company, on behalf of BASF.
Ms Brown sent samples to a BASF laboratory in Germany for testing. The genetic screening found the unexpected mutation.
“This was an inadvertent discovery,” Ms Brown said. “But now that we have recorded the first known occurrence of the F129L mutation in barley net form of net blotch in Australia, it is important to share this knowledge with the industry. The mutation confers reduced QoI fungicide efficacy against this disease."
Ian Francis, BASF head of development – crop protection said this is a finding the industry needs to be aware of and potentially investigate further. “Overseas experience shows that this mutation doesn’t necessarily create full QoI resistance in net blotch.
“However, barley growers and agronomists now need to be even more mindful of their management strategies for the disease. We’ve found the mutation randomly, so it’s likely to be more widespread. As a matter of good stewardship, we should be on the lookout for it and growers should be proactive in their rotation of different fungicide groups.”
Mr Francis said BASF continues to work on delivering product innovations to the market and supports strong stewardship of crop protection products. It encourages industry to integrate good agronomic practices such as crop rotations, varietal selections and rotation of chemistry to strengthen the management of pests and diseases.
BASF will also continue to focus on fungicide research and development and work with the barley industry in managing NFNB.
BASF researchers detect F129L mutation in barley leaf samples infected by net form of net bloch (NFNB)
This is the first known occurrence in Australia
the mutation can reduce the sensitivity of crop diseases to Group 11 (QoI) fungicides
The discovery is a reminder of the need to implement integrated disease management strategies to help manage the development of fungicide resistance.
