Tiny ancient fungi could slash Aussie fertiliser bill
A mysterious ecosystem of fungi weaves the soil like spider silk, helping plants and crops grow.
Arbuscular mycorrhizal fungi, which take their name in part from the Greek word meaning root, provide plants with necessary nutrients and water; It’s a critical connection that has been quietly evolving underground for billions of years.
“This is the oldest relationship you can have,” Western Sydney University ecologist Adam Frew told AAP.
“Before plants evolved to have roots, they were associated with these fungi.
“Most plants still have these relationships with the same group of fungi.”
But despite their ancient existence supporting plant life, water cycles and humanity, understanding of how fungi can be targeted to increase food yields is limited.
While scientists have long understood the potential of fungi in agriculture, applying it strategically to crops has been challenging because different species thrive under a variety of plants, soil types, and climates.
Dr Frew and a team of researchers created Australia’s first database of arbuscular mycorrhizal fungi, taking samples from 610 sites across all major climate zones.
The samples, collected by scientists and farmers over more than a decade, allow researchers to play “matchmaker” between fungi and different crops.
The fungi can then be applied to seeds, soil or crops to improve plant health and build soil carbon.
“If we know enough to say that this fungal species is suitable for a region, knowing that we will get positive effects, we can produce inoculants for that particular species,” Dr Frew said.
“Then maybe farmers can apply this to increase the presence of certain species or make sure their farm management practices support those fungi.”
It is hoped that matching fungi with the right crops and soils could help farmers reduce fertilizer costs and reduce reliance on imported inputs, which will cost Australia more than $3 billion by 2025.
Australia is entirely dependent on imported urea fertilizer, with 62 percent of supply coming from the Middle East, according to the agriculture ministry.
The closure of the Strait of Hormuz triggered by the Iran war caused fertilizer prices to skyrocket to $1,400 per ton in April and May.
At the same time, Australian agriculture loses billions of dollars each year to infertile soil, pests and diseases, increasing reliance on fertilizers and pesticides.
Dr Frew said harnessing the power of fungi had the potential to reduce inputs and improve soil quality, but it was not a silver bullet.
“You always need some sort of input, soil doesn’t have an endless supply of nutrients,” he said.
“This is about trying to increase efficiency.”
Dr Frew will present his research at the International Mycorrhiza Conference in Cairns on 12 July.
