Ahri Snapshots

In this podcast, Jessica Strauss chats with then AHRI PhD Candidate Gayle Somerville about her paper “Modeling the impact of harvest weed seed control on herbicide resistance evolution”.The modelling in this paper was a component of the PhD research of AHRI PhD student Gayle Somerville, who is now a postdoc at Arhus University in Denmark.Harvest weed seed control (HWSC) is a term that describes a range of techniques to capture and destroy weed seed on standing weed plants infesting crops at the time of grain harvest. HWSC techniques have become adopted by many Australian grain growers, with AHRI research in HWSC led by Michael Walsh (now at University of Sydney). HWSC is currently being evaluated in other parts of the world. The objective of HWSC is to target weed seed at grain harvest to minimise weed seed injection into soil seedbanks and reduce weed densities over time.It's well understood that herbicide resistance evolution in weeds would be much slower if any herbicide resistant individuals were ann

In this podcast, we chat with InterGrain Research Officer Hannah Robinson. Not too long ago she completed her PhD at the University of Queensland (which was funded by GRDC), looking primarily at identifying the genes controlling root architecture in barley. Some significant discoveries were made during this time, including identifying a key gene in barley that enables the plant to access water stored deep in the soil during droughts. Hannah shares how this discovery was made and the potential impacts. She also discusses her work at InterGrain, sharing how she tries to ensure crop traits discovered through research can be incorporated into new varieties. Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Tony Swan is back to discuss his latest research findings! We've previously highlighted in AHRI insight and the podcast, research by Tony Swan and the team from CSIRO that demonstrated double breaks (ie. growing two break crops in sequence) were more effective in reducing annual ryegrass numbers to manageable levels than a single break crop or continuous wheat.The research team took this one step further in a project involving FarmLink in southern NSW from 2014-2017, comparing rotation strategies between disc and tyne seeding systems in a stubble retained system and their impact on ryegrass, yield and profitability.We'll be publishing an AHRI insight which will go into further detail about the results, but you can get the highlights in this podcast!Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

This podcast looks at trifluralin resistance, with AHRI Director Stephen Powles. The results out of a recent AHRI, entitled Novel Tubulin Mutations Conferring Resistance to Dinitroaniline Herbicides in Lolium rigidum are the primary focus. Steve explains that this study clearly and comprehensively establishes that target site resistance to dinitroaniline herbicides, such as trifluralin, can be endowed by a mutation changing the alpha tubulin gene at amino acid 243, changing Arg to either Met or Lys.  He explains how this works, as well as looking at how common trifluralin resistance is; the differences between target site and metabolic resistance, as well as the implications of these findings in the field.You can read the paper in full here: https://ahri.uwa.edu.au/publications/novel-tubulin-mutations-conferring-resistance-to-dinitroaniline-herbicides-in-lolium-rigidum/But you might like to listen to the podcast first, as its one of the more tricky concepts to get your head around!Take a listen!Music: bensoun

In this podcast, we chat with Professor Martin Vila-Aiub, who is currently on sabbatical at AHRI from the University of Buenos Aires. Martin is a good friend of AHRI, visiting a number of times on sabbatical and also completing his PhD here between 2001-2005.  As you'll learn in more detail in this podcast, in his sabbatical period this time at AHRI, he will write a review on the impact of resistance endowing mutations on plant fitness. We also hear from Martin about the differences in farming between Argentina and Australia and we talk conceptually about what would happen if there were more fitness penalties.Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Every five years, Mechelle Owen, one of our dedicated AHRI researchers, undertakes the massive task of visiting 500 fields in Western Australia just before harvest to sample seeds of surviving weeds for resistance testing with GRDC support.So far, we have reported on the results from the latest survey in AHRI insight, looking at ryegrass resistance. You can check it out here: https://ahri.uwa.edu.au/has-herbicide-resistance-in-ryegrass-in-wa-plateaued/In this podcast, Mechelle gives an overview of her results so far. We'll be publishing further podcasts and blog posts on Mechelle's research as the data is analysed and published. Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

AHRI was recently lucky enough to be visited by Professor Baruch Rubin from the Hebrew University of Jerusalem. Baruch completed a sabbatical in AHRI 15 years ago, so we were delighted to welcome him back for his short visit. In this podcast, Baruch commentates on night spraying and sheds light on some of his research in this area. He also gives insights into how farming systems in Israel compare to those in Australia.Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

In this podcast, Jessica Strauss chats with Dr Richard Smith, who is an Associate Professor of Cropping Systems Ecology and Management at the University of New Hampshire and currently on sabbatical leave at AHRI.Dr Smith’s research addresses the roles that ecologically-informed management and crop plant diversity play in promoting species interactions that benefit agriculture and weed management. In addition to his research and teaching responsibilities, Dr Smith is also an Associate Editor for the journals Weed Research and Agroecology and Sustainable Food Systems. Jessica talks to Richard about his work and also finds out about some of the core differences between farming in Australia and New Hampshire, where Richard is based.Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

This podcast with AHRI Principal Research Fellow Dr Qin Yu focuses on explaining some of the more tricky aspects of the paper:A double EPSPS gene mutation endowing glyphosate resistance shows a remarkably high resistance costThis paper was a collaboration between AHRI researchers Heping Han, Qin Yu, and Steve Powles, as well as past AHRI researchers Adam Jalaludin and Martin Vila-Aiub.AHRI researcher Heping Han and others with GRDC support recently found a large fitness penalty in glyphosate-resistant crowsfoot grass. We have previously reported on this glyphosate resistance here. At the time we could see by looking at the pictures of the plants that the ones with the homozygous TIPS mutation were severely stunted. The researchers have now further investigated this and found that the homozygous TIPS plants have 50% reduction in seed set and this escalates to 85% in plants that are in competition with a rice crop.The TIPS mutation that causes high-level glyphosate resistance affects plant fitness. The TIPS mut

With the exciting news of Hugh Beckie being announced as the new AHRI Director (commencing in July 2018), we thought it might be fitting to release this interview we did when he was here in Perth.Hugh discusses the issue of wild oats in Western Canada and the tactics being used to control this weed. We then hear from AHRI extension officer Paul McIntosh, who gives us a local perspective, discussing the issues which the northern region are facing with this weed (which is also known as black oats).Dr Hugh Beckie will commence as AHRI Director in mid-2018Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Weed population simulations can be useful to predict the effects of alternative management practices on herbicide resistance evolution. Almost all previous simulations have ignored the possibility of within-field spatial structure in a weed population, instead, making the implicit assumption of perfect dispersal and spatial homogeneity in population density and genetics.The effects of this simplifying assumption have not been examined, despite the fact that dispersal limitations and spatial structure within the population are likely to occur and to affect the evolution of resistance. Therefore, previous AHRI researcher, Dr Gayle Somerville, with her team, developed a new spatially-explicit model called SOMER, and examined how changing the following factors affected the predicted evolution of resistance: the degree of spatial resolution used in the model; whether resistance was semi-dominant or fully-dominant; distances of pollen and natural seed dispersal; and inadvertent collection and grain harvester weed s

Dr Catherine Borger (pictured above) from the Department of Primary Industries and Regional Development talks about one of the GRDC projects she's working on in this podcast with the host, Jessica Strauss. The project, run by Dr Gurjeet Gill from the University of Adelaide is looking closely at a range of weed species to find out more about the basic ecological facts about them.Dr Borger said there were many weed species out there where there's a lack of understanding about weed population growth rates; their seed set; their ability to shed seeds at different times and the effect on harvest weed seed management. These are some of the core areas being investigated in the project.This podcast looks closely at brome grass and annual ryegrass. There is lots of data on ryegrass, but it was used as a point of comparison to the other weeds being investigated in the project.Ryegrass still is Australia's biggest weed problem, however, Dr Borger said brome grass is catching up.Take a listen to the podcas

Recently Jessica Strauss caught up with Department of Primary Industries and Regional Development Principal Research Officer Dr Abul Hashem to talk about research he and Dr Catherine Borger have done on the interaction between soil pH, weeds and crops. Soil acidity limits productivity on approximately 50% of Australia’s agricultural land and several important weed species have a competitive advantage over broadacre crops on soils where the surface soil pH level is less than 5.5 or the subsurface pH is less than 4.8.Dr Hashem said efforts to improve soil pH had a two-pronged effect on crop production. “Firstly, agricultural crops yield better when they are grown in soils where the pH is in the optimal zone and secondly, crops are better able to compete with weeds. Having lower weed numbers in-crop means the herbicides applied are more likely to be effective and also there is less potential for weed seed to be added to the soil’s seed bank.”In this podcast, Dr Hashem explains there's still further work nee

Research by Cathryn O’Sullivan from CSIRO is showing that some weeds release chemicals from their roots that slow down the bacteria that are essential to the nitrogen cycle, retaining nitrogen in the ammonium form that weeds can potentially take up faster than crop plants.In this research, Cathryn focused on some common Australian weeds, including wild radish, brome grass, wild oats and annual ryegrass. Wild radish was particularly strong in being able to manipulate the nitrogen cycle, demonstrating why it's so competitive with the crop. For more on this research, take a listen to Jessica Strauss chatting with Cathryn O'Sullivan on the podcast below. Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Sowthistle is the kind of weed which can be a pain all-year-round. It's particularly problematic for farmers in the North-Eastern part of the country. Jessica Strauss talks to Principal Research Scientist from the Queensland Department of Agriculture and Fisheries, Michael Widderick, about the strengths and weaknesses of this weed and how to manage it effectively, based on Michael and other's research.You can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Dr Todd Gaines recently visited AHRI and took time out to explain the significance of AHRI Director Stephen Powles' award. Steve recently won the American Chemical Society International Award for Research in agrochemicals.He's the first Australian to win the award, which is given to a scientist who has made outstanding contributions to the field of agrochemicals at the international level, with their vision and sustained contribution having opened new horizons for investigators in their field and beyond.Steve was recognised for his long-standing research contribution to identifying the role of cytochrome P450 enzymes in endowing herbicide resistance in plants.Steve was nominated for the award by Todd Gaines. Todd previously was a postdoctoral student of Steve, who spent three years as a researcher at UWA before returning to the US.Todd discusses what he's been up to and also goes into some detail about what P450s are as well. Take a listen!Music: www.bensound.comYou can follow AHRI on Twitter h

CSIRO wheat breeder Dr Greg Rebetzke talks to Jessica Strauss about the research being conducted into developing a new high vigour wheat. What if we could have a wheat variety that could play the yield game and the competition game? What would that look like? Perhaps a dwarf wheat, with a long coleoptile, prostrate growth habit (like barley), early vigour, leaves like solar panels, and of course, high yield. Well, that’s exactly what Greg is attempting to develop as part of a GRDC-funded high vigour wheat project. High vigour kinds of wheat are not only good for competing with weeds; they also serve to shade the soil to reduce evaporation and ultimately increase water-use efficiency.To find out how this breeding program is progressing, and what difference high vigour wheat makes to ryegrass seed set, take a listen. You can also read more about this project in AHRI insight: http://ahri.uwa.edu.au/how-a-new-wheat-variety-could-compete-with-weeds-like-jonah-lamu-did-on-the-field/Music: www.bensound.comYou can fo

You may have used the handy Ryegrass RIM AHRI developed. Now, thanks to the efforts of CSIRO and GRDC, as well as AHRI, new RIM models for both brome and barley grass will become available to use by farmers, agronomists and researchers. CSIRO Farming Systems Scientist Rick Llewellyn explains why the new models have come about, how they can be used and the benefits of using them in this podcast with Jessica Strauss.For some more info on Ryegrass RIM: it's a hands on, user-friendly decision support software that allows farmers and advisors to evaluate the long-term cropping profitability of strategic and tactical ryegrass control methods, on the long-term and at the paddock scale. RIM lets you test your ideas: How can you run your ryegrass down and profit up? New rotation? New technique? You can check it out here: http://ahri.uwa.edu.au/research/rim/Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

We're really fortunate to have excellent Chinese visiting scholars and Ph.D. students at AHRI. In this podcast, Steve Powles chats with Jessica Strauss about how the win-win program started. Dr. Yu Qin, is the senior researcher at AHRI and manages all the Chinese scholars and Ph.D. students. She regularly visits China and recruits students to continue their studies at AHRI. Steve explains how that all began. We also learn in more detail about what visiting scholars Dr. Qiong Peng and Dr. Xia Yang are focusing on in their research here at AHRI. We also learn more about our Ph.D. students, Jinyi Chen, Huan Lu and Lang Pan.Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.

Much like we promote rotating herbicides to keep them working, Mike Ashworth explains in this podcast how mixing up how non-herbicidal weed tactics are applied, helps maintain their effectiveness too. AHRI is currently looking further into this with research work being conducted at our Shenton Park research facility. Mike chats to podcast host Jessica Strauss about this research, and also provides some great information for both agronomists and farmers to take on board in regards to non-herbicidal tactics, such as 'disruptive rotations'. Find out more by taking a listen.Music: bensound.comYou can follow AHRI on Twitter here. To learn more about AHRI's research and team, check out the website here.