Australia's early weed resistance informs PNW path forward
By Ian Burke and Arron Carter
We’re in a very different world now from the one that five of us left last February for a two weeks fact finding tour of Australia to investigate that country’s response to weed resistance and weed management.
Besides ourselves, the group included Washington Grain Commission CEO Glen Squires and WGC commissioners Gary Bailey and Brit Ausman.
A trip to Australia like the one we arranged can’t occur now, and likely won’t be possible for years to come. The COVID-19 pandemic has fundamentally altered the life we practiced in the past.
There is no way to compare the magnitude of the impact of a global pandemic to the impact of herbicide resistance on the farm, except perhaps like this: When herbicide resistance evolves sufficiently, the impact to the farming system is such that you have to stop what you have been doing and find a completely different way. As farmers have already learned from resistance issues and the world is now learning from the pandemic, that’s not easy.
Australian wheat shares many similarities to United States wheat, particularly wheat grown in the Pacific Northwest. Like PNW wheat, Australian wheat is primarily produced for export to southeast Asia. But it wasn’t always that way.
Wheat is a relatively new crop for Australia. Historically, sheep were raised in what is now the country’s wheat belts, and sheep need food. The Australians, ever pragmatic, found the best forage grass they could – rigid ryegrass – and planted it in dense stands throughout the wheat belts. If that sounds unusual, consider that in the United States we once tried cheatgrass as a forage, only we didn’t have to plant it, the cheatgrass took care of that itself.
Rigid ryegrass is an incredible plant species. It is what weed scientists like to call ‘very adaptable’. When you add a species like rigid ryegrass into a production system like that used in Australia, where there is essentially no government support for crop production (farm programs don’t exist, and insurance is very expensive), you get herbicide resistance. Quickly. Shockingly fast, in fact.
Australia wheat farmers no longer have any postemergence herbicides that are even moderately effective for controlling rigid ryegrass. As new herbicides were introduced, one by one in the 1980’s and 1990’s, they were used like products coming off a seemingly endless conveyer belt. Rigid ryegrass evolved resistance to all of them, often within a few years of introduction.
As a consequence, Australia was the first country to create a ‘Resistance Initiative’ to help farmers deal with the threat. Australian farmers have also evolved. Those who are left are very good at what they do and based on the recent trip organized by the Washington Grain Commission (WGC), we can learn a lot from them.
The GRDC effect
The Grains Research and Development Corporation (GRDC) is one of a few Research & Development Corporations that were created when Australia opted to privatize agricultural research and support in the 1980’s. The GRDC is still funded by the government, but it is also supported by the equivalent of checkoff dollars from farmers.
Functionally, the Australians’ combined parts of the U.S. Department of Agriculture (USDA) and various state grain commissions (like the WGC) into a single entity to support grain farming. There is no ‘land-grant’ university system, or a Cooperative Extension Service. Instead, the GRDC funds research at various universities based on their location and specialization.
Where the small grain farmers in the U.S. benefits from federal Hatch Act dollars flowing to WSU, the GRDC has to pay for the entirety of crop research. That has translated into efficiency and specialization on the part of Australia’s weed science programs and it resulted in plant breeding being privatized. The only public plant breeding in the country is essentially pre-breeding for new or novel traits, managing quality, or creating new grain production systems.
Overall, the effect has led to the GRDC organizing farm support as well as providing national strategic guidance for farming research, including herbicide discovery.
Specialization in Australia
Specialization and efficiency were two attributes of the Australian system that stood out during our visit. We started our visit by meeting with staff at the Australian Herbicide Resistance Initiative, (AHRI) an organization singularly focused on understanding and mitigating herbicide resistance. The next stop was with InterGrain, a company focused on plant breeding. Our third stop was with a private crop research company that focuses on conducting field research trials, including variety trials.
At every visit, we interacted with Australians who were remarkably focused on doing critical grains research in support of the overall system. Each entity did their ‘thing’ very well.
We had the opportunity to visit three weed science research programs in Australia. In western Australia we visted AHRI, led by Prof. Hugh Beckie, in Adelaide we visited Prof. Chris Preston and his research program, and we visited Prof. Michael Walsh’s program at the University of Sydney. Although herbicides were involved in the research programs, the overall lack of new herbicides coupled with farmer and farm consultant expertise reduced the need to conduct the sort of herbicide efficacy research conducted in the United States.
Instead, the Australian weed science research groups conduct targeted integrated weed management research. They also operate weed resistance testing programs. Testing for resistance is widely used by Australian farmers, even though it is quite expensive. One of the most eye-opening aspects of Australian farmers behavior was their proactive response to weed resistance. Sending in weed seed samples for resistance testing is standard operating procedure.
Plant breeding in Australia is privatized and the system for collecting royalties is different than ours. Instead of paying royalties when purchasing seed, the farmer reports the variety at grain delivery. The royalty stream is then directed back to the company based on those reports. It means that farmers can save seed and every farm we visited had a seed cleaner.
There are positives and negatives to any system. The Australian seed system can be gamed when farmers report a variety different than the one they actually grew. On the positive side, there is likely less farm-to-farm seed contamination during planting.
Where public plant breeding does occur it is singularly focused on a particular problem. Plant breeding as a scientific endeavor is managed by the Commonwealth Scientific and Industrial Research Organization (CSIRO), which is substantially similar to the USDA-Agricultural Research Service for agricultural research.
CSIRO is engaged in breeding for wheat competitiveness with wheat. It’s not a new idea, but they have brought a very creative spin to it. For instance, we were introduced to wheat varieties with leaves as wide as a corn leaf.
The ‘aren’t farming’ statement
February is high summer in Australia, meaning days of 110 degrees F. Although there were no crops in the ground at the time, we were able to tour five farms in Western Australia and visit with farmers, all of whom were eager to share and discuss aspects of their business.
We were all struck by their engagement with independent consultants. A consultant might assist as many as 30 farmers in an area. The smallest farm we visited was 10,000 acres.
We were astonished to learn how they lime. It’s routine to spread low grade lime derived from beach sand on wheat fields during summer. The rate is low, and the lime is applied regularly. Our hosts were blunt. As they put it: If you aren’t liming, you aren’t farming.
Farmers consider essential activities to be those that were it not to occur would potentially lead to farm failure. Liming and weed management were discussed in the same breath.
Weed management and IPM in practice
When it came to weed management, the farmers we visited could specifically identify and talk about the multiple integrated weed management techniques they were using. All of them tram-line (a farming system built on permanent wheel tracks where the crop zone and traffic lanes are permanently separated). They also chaff-line, (placing a chute on the rear of the harvester that concentrates the chaff into a single line). These practices result in most of the rigid ryegrass seed being placed in the drive line of the combine (and all of the other equipment used in the field).
All of the farmers we spoke with expressed interest in seed destructor technology, where a hammer mill is fixed onto a combine, and the weed seed is fed through it, but none felt it was quite worth the cost. A chaff-line setup on a combine could be rigged for less than a $1,000, and was viewed as effective enough.
All of the farmers had their consultants arrange for herbicide resistance testing where needed.
Weed management research, and particularly herbicide resistance management research in Australia is very advanced and is managed from the GRDC down to the farmer in an efficient and organized system. The farmers we spoke to indicated herbicide resistance was one of the primary issues their farms faced.
As researchers, we have both been to a myriad of meetings and events while serving the wheat industry, but our tour of Australia was the most educational and impactful of all. Our discussions and tours showed substantial similarity in the complexity and practice on farms “Down Under” to our own wheat farms and the farming systems of the PNW.
We look forward to integrating what we learned into our programs and spending the future capitalizing on the linkages and ideas about weed resistance and weed management that we gained during the journey.