From the start of her career, GRDC Research Fellow Dr Elizabeth Czislowski, from the Centre for Crop and Disease Management at Curtin University, has been fascinated by fungal pathogens and their management.
Her PhD at the University of Queensland allowed her to investigate what drives host-specific pathogenicity, while various postdoctorate positions enabled her to explore the development of new fungicide technology.
Dr Czislowski is now continuing her passion with a GRDC Fellowship, looking to find sustainable, long-lasting and safe solutions to reduce the impact of pathogens on farming systems.
She says with growers largely relying on just 3 unique fungicide groups to manage disease, it’s no surprise the industry is seeing unprecedented levels of fungicide resistance, highlighting a critical need for more fungicide options.
Dr Czislowski believes it’s time to think beyond chemical-based fungicides and to search for options that effectively combat disease without compromising environmental sustainability or human health.
“Single-site fungicides work by binding to a single protein within the pathogen cell and by inhibiting the function of that protein, which is essential to the pathogen’s survival,” she says.
So we were thinking, what if there’s a different way to stop these proteins from functioning – what if we could wrap them up or encapsulate them somehow and stop their activity, using something other than chemicals?
DNA nanoparticles as a potential fungicide option
As part of her fellowship, Dr Czislowski is investigating DNA nanoparticles – extremely small DNA-based structures – and whether they can be developed to interact with fungi and used in a similar fashion to fungicides.
By developing the nanoparticles to bind and inhibit essential fungal proteins, the resulting technology could be a game changer for future crop protection.
She says DNA nanoparticles have been used in biomedical research for years, but this is the first time, to her knowledge, these particular nanoparticles have been used in agriculture against fungal pathogens.
“And what’s more exciting is there’s potential for us to design them to be biodegradable and biocompatible, improving safety and specificity of crop protection technology for the future,” she says.
A fungal pathogen, Parastagonospora nodorum, tagged with a green fluorescent marker that has been treated with nanoparticles tagged with a pink fluorescent marker. The particles are shown to encapsulate the growing cells (called hyphae) of the pathogen. Photo: Dr Elizabeth Czislowski
The fellowship project has 3 aims: finding suitable fungal protein targets, developing the nanoparticle-target protein interface, and building/testing nanoparticles on pathogens to disrupt their function.
Just 6 months into the fellowship, the initial stages of computer and laboratory work for developing the nanoparticles has begun, with plans to use Parastagonospora nodorum – the pathogen causing Septoria nodorum blotch in wheat – as a model fungal organism.
“We’re using Septoria nodorum blotch because we have a lot of genetic resources for it here at CCDM, with the hope that the nanoparticles we design can be used across all fungal pathogens of grains, from wheat powdery mildew to grey mould and beyond.”
Ensuring the technology can be applied like a fungicide
Curtin University is supporting Dr Czislowski’s work as an early-career researcher by facilitating the recruitment of a PhD student, building further research capacity in future generations.
With a vision to apply the technology to plant leaves like a traditional fungicide, the PhD student will investigate whether nanoparticles can adhere to and remain intact on the crop canopy.
“We’ve already run some initial studies that have shown they do stay intact, so that’s really promising, as it’s important to look at both sides of the coin,” Dr Czislowski says.
“The PhD project will go a bit deeper and address questions such as where do the nanoparticles go once sprayed onto a plant? Are they entering the fungus? And how long are they stable for?”
Dr Czislowski says she’s looking forward to seeing the outcomes from her nanoparticle work.
It’s futuristic and blue-sky, with the pathway to market still unclear, but it has great potential to provide some strong alternative solutions to disease control in the future.
