Robert Henry gazes ruefully northwards from the University of Queensland’s St Lucia campus, caught between feeling excited and a niggling regret.
“There’s a supermarket out there … but most Australians don’t even know it,” he said.
His excitement stems from this ‘supermarket’ being the enormous untapped food and cropping potential of countless indigenous plant species that a small, though growing, body of scientists are realising could be a genetic bounty holding a critical key to the planet’s food security. Internationally, northern Australia in particular, is already being talked about as the frontier for new plant genetics. Robert Henry’s regret is that by-and-large it remains a blind spot for Australians. Most of the interest and research is being driven from overseas.
“Take wild rice which is abundant across northern Australia from Townsville to the Kimberley. I’m considered the local expert, but most of what I know is from Japanese scientists who have been studying our wild rice for 20 years,” he said.
Robert Henry, Professor of Innovation in Agriculture and Director of QAAFI said it is becoming increasingly clear that Australia is home to an enormous diversity of indigenous grain-bearing grasses, pulses and fruits of potentially huge value to plant breeders needing to bolster domesticated crops with increased climate resilience and pest and disease resistance.
“We have rice, ancestral grasses related to domesticated cereals, our own soybean, sorghum, mungbean, pigeon pea; even citrus and grapes, but they have mostly been overlooked because of a long-held, false, assumption that our only food crops are those introduced through European settlement.”
Professor Henry believes this landscape ignorance may have arisen from a basic misunderstanding of the Aboriginal use of these plants. “It was often noted by explorers and settlers that indigenous people didn’t undertake any traditional cultivation; the conclusion being that there were no crops to farm. Now, however, we are beginning to realise that indigenous plants bearing edible seeds and fruits were in such abundance naturally that a transition to farming, in the European sense, just wasn’t required.
“For example, native rice is present in such abundance and in naturally weed and disease-free stands that you don’t need to plant it and manage it. You just harvest and store … activities that were observed and recorded, but not understood. We were blinded to the significance of this by our need to see crops being cultivated.”
Professor Henry is now working on a project for the CRC for Developing Northern Australia to scope the potential for a rain-fed rice industry in the north based on local genetics: “We have learned that when we take Asian varieties into the north they only grow until pests and diseases find them. Native rice doesn’t have this problem, which points to an opportunity to identify these resistance genes and back-cross into a high-yielding Asian rice.
He describes native species as “unknown, underutilised, underappreciated”; a perspective he hopes to help change.
A measure of the opportunity (and historical ignorance) is DNA analysis is revealing that some of the plants like rice and soybeans (genus Glycini) that were assumed to be wild survivors of species introduced by early human migration, actually originated here.
Australian wild rice, for example, was assumed to have been brought to Australia from Asia and this may be why it has been ignored by breeders. However, research has now shown the Australian varieties are quite distinct and therefore likely to possess considerable genetic diversity that hasn’t been captured in domesticated varieties.
Such potential locked up in native germplasm is now one of Professor Henry’s primary interests in his agricultural innovation portfolio.
“It’s the same with soybean. There is an increasing realisation that most of the genetic diversity for Glycini is right here. We’ve found at least eight species in Queensland alone that we have yet to even name,” he notes. “And all the timee we have been struggling to adapt introduced varieties to our variable climate … we’ve had our own.”
Professor Henry is also studying wild sorghum in a joint project with Professor Ros Gleadow from Monash University in Melbourne: “The sorghum we grow commercially was domesticated in Africa, but the sorghum genus is Australian. All of the species exist here, mostly in Queensland, but apart from a Texan variety that has used genes from a wild Queensland sorghum, this resource also has largely been overlooked even though we have identified traits that could deliver bigger grains and help get sorghum into the human foods market.”
Native citrus has gained some recognition through the finger lime, Citrus australasica,
and the round lime, Citrus australis. Professor Henry said there are four Australian citrus species and all potentially have useful disease-resistance traits for domesticated species, as well as an early flowing trait that the American citrus industry has exploited to breed earlier fruiting trees.
Other fruits include wild grapes found to be of Gondwana origin – the super continent that split-up about 180 million years ago to form the landmasses we know today as Australia, Africa, South America, Antarctica, the Indian subcontinent and the Arabian Peninsula. Professor Henry said the grapes’ adaptation to a rainforest environment in Queensland has made them resistant to fungal pathogens: “This could provide the modern-day industry with some very exciting rootstock potential.”
Another example of this extraordinary unfolding story that is destined to re-write Australia’s agricultural history is pigeon pea. Australian farmers have been trying to build production to supply potentially high-value markets on the sub-continent, but the introduced varieties have struggled under pest and disease pressure. Now it has been found that most of the global biodiversity for this plant exists in an agroecological zone stretching between Townsville and Mount Isa. Again, the genetics that could protect the commercial crop are already here.
What all this amounts to, said Professor Henry, is the presence in Australia of indigenous genetic resources that have the potential to improve crop performance – in Australia production systems and elsewhere.
He believes that exploiting this resource would herald a second Green Revolution. The first Green Revolution, in the 1960s, used selective breeding to increase the ratio of grain to plant matter (the higher harvest index approach). Professor Henry believes there is as much to be gained again by capturing wild diversity that hasn’t yet been incorporated into domesticated crop gene pools.
Serendipitously with the growing awareness of this potential is the advent of new breeding technologies: “Until now we simply haven’t had the tools, but modern pre-breeding allows us to accurately identify, and bring in, those genes and use genome sequencing and analysis to guide rapid back-crossing.
“It’s an exciting new opportunity for agriculture because a lot of what we are growing today is based on something that was domesticated 10,000 years ago. Faced with climate change we have to broaden that genetic base. Exploiting the biodiversity existing in indigenous crops that are related to many introduced commercial varieties is one such technological opportunity, but right now there isn’t any concerted effort to research this potential.”
However, Professor Henry is confident this will change, especially if the national mindset can be moved from asking ‘what do we have’ to ‘what don’t we have’.
“That’s exciting because the evidence is mounting that we probably have a bit of everything.”
Plum pickings: ancient fruit ripe for modern plates
An Indigenous fruit which is one of the earliest known plant foods eaten in Australia could be the next big thing in the bush foods industry.
The University of Queensland research team is led by bush foods researcher Professor Yasmina Sultanbawa, who said the green plum not only tasted delicious but contained one of the highest known folate levels of any fruit on the commercial market.
“This is really exciting because folate is an important B-group vitamin, and what’s great about the green plum is that the folate is in a natural form so the body absorbs it more easily than in a capsule,” Dr Sultanbawa said.
Folate performs many functions in the body, including helping cells work and tissues grow, and is regarded as essential for the healthy development of the foetus during pregnancy.
Her team is undertaking the world’s first detailed study of the nutritional characteristics of the green plum (Buchanania obovata).
“The green plum is sometimes called ‘wild mango’, and grows abundantly across the far north of Australia,” Prof Sultanbawa said.
“There is recent evidence discovered in West Arnhem Land which shows the green plum was eaten by Aboriginal people as far back as 53,000 years ago.”
With funding from the Australian Research Council’s Industrial Transformation Training Centre’s program for Uniquely Australian Food, Prof Sultanbawa is working with Aboriginal communities in East Arnhem Land and Delye Outstation in the Northern Territory, to research the green plum.
Ms Selina Fyfe, a food scientist who is undertaking a PhD on the green plum, says the sensory qualities of the green plum are outstanding.
“It’s probably one of the most delicious foods I have ever tasted – it’s very sweet, a bit like stewed fruit,” Ms Fyfe said.
“The research has already found the green plum’s flesh is high in protein, dietary fibre, folate, potassium and is a good source of magnesium, calcium and phosphorous.”
The seed of the green plum is also rich in dietary fibre, iron and vitamin B9.
The green plum belongs to the family Anacardiaceae which contains well-known commercialised fruit including mango, cashew apple and pistachio nuts.
“The green plum is a sweet fruit that consistently rates highly in the consumer taste tests we’ve run in Brisbane and could one day be as popular as table grapes,” Prof Sultanbawa said.
“A lot of people don’t know about the green plum, even within the bush foods industry.
“This is a wild-harvested, seasonal fruit that typically ripens after the first rains of the wet season in late November/early December.”
The fruit is eaten raw from the tree or as dried fruit, and the plum’s flesh and seed can also be mashed into an edible paste.
Prof Sultanbawa said the green plum was traditionally used as food and medicine in Aboriginal communities across the Top End of Australia and was very popular with the children and elderly.
“The green plum has so much goodness, it could one day help with dietary issues like the triple burden of malnutrition – undernutrition, obesity and micronutrient deficiencies – known as hidden hunger,” Prof Sultanbawa said.
“Our collaborators at the Aboriginal-owned Gulkula nursery in Gove, East Arnhem Land, have recently successfully propagated the green plum – and we believe this is the first time the plum has been propagated anywhere in the world.
“The Arnhem Land Progress Aboriginal Corporation for the first time did a trial harvest of the green plum this year.”
The UQ team, which includes A/Prof Heather Smyth, Dr Michael Netzel and Dr Horst Schirra, is working with Professor Philippe Schmitt-Kopplin from the Technical University of Munich and the Helmholtz Zentrum München and Professor Michael Rychlik from the Technical University of Munich in Germany to uncover the green plum’s chemistry, and its acids and sugars, to provide a more detailed nutritional profile of the fruit.
“Once we get the scientific evidence about its nutritional value, chemical composition, the different maturity stages, and the best time to harvest, we can then work with the communities to get it into the market as a commercial product.”
Prof Sultanbawa said legal and social science researchers, and other partners in the ARC Centre for Uniquely Australian Foods, would work with Indigenous communities to undertake enrichment planting and develop enterprises that ensure Indigenous community ownership and control.
This research is supported by Arnhem Land Progress Aboriginal Corporation, Gulkula Mining Corporation, Dhimurru Rangers, Mata Mata Homelands, Wild Orchard Kakadu plum Pty Ltd and funding from the Australian Research Council, The University of Queensland, the Department of Agriculture and Fisheries, Australian Native Food and Botanicals, the Kindred Spirits Foundation, Karen Sheldon Catering, Beeinventive Pty. Ltd., and Venus Shell Systems Pty. Ltd.
Contact: Professor Yasmina Sultanbawa, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland E: email@example.com, M: +61 455 934 640 or A/Prof Heather Smyth, Senior Research Fellow, QAAFI, The University of Queensland, T. 07 344 32469, M: 0468 732 394 E. firstname.lastname@example.org
Media enquiries and photo requests: Margaret Puls, QAAFI Communications, E: email@example.com M: 0419 578 356.
Photos: Indigenous elders show researchers native bush foods grown in the Northern Territory of Australia.
Wild rice growing in northern Australia’s crocodile-infested waters could help boost global food security, say University of Queensland researchers who have mapped its genetic family tree.
Valuable traits from the wild rice – such as drought tolerance and pest and disease resistance – can be bred into commercial rice strains, said Professor Robert Henry from the Queensland Alliance of Agriculture and Food Innovation.
“Northern Australia’s wild rices contain a wealth of untapped genetic diversity and at least two species are very closely related to domesticated rice, so they can be cross-bred with this species,” he said.
“Wild Australian rice genes could make commercial rice production better suited to northern Australian conditions.
“The wild rices could contribute resistance to diseases such as rice blast, brown spot and bacterial leaf spots.”
Professor Henry said the research showed that in the era when the ancient human ancestor known as Lucy lived in Africa, a genetic divergence occurred in the rice variety that is now found only in northern Australia.
This divergence led to the Asian and African rice species commonly used in commercial rice production today.
Professor Henry said that in addition to boosting global rice production, Australian wild rice offered the opportunity to be cultivated as a tasty and nutritious product in its own right.
“It tastes good and we believe it may have more beneficial health qualities than other rice species,” he said.
A UQ doctoral thesis study on the grain quality of Australian wild rice showed the species had the lowest “hardness” of cooked rices, and a higher amylose starch content.
“The higher the amylose content, the longer the rice takes to digest,” Professor Henry said.
“This potentially offers more nutrition to our gut microbes, in the same way high-fibre foods do.”
He noted that human trials were needed to confirm the health benefits but the chemistry suggested this was the case.
Rice is the most widely consumed staple food for much of the world’s population and it is the third-largest worldwide agricultural crop.
Professor Henry said the study provided a comprehensive insight into the rice family tree, and confirmed that wild Australian rice was the most directly related species to the ancient ancestor of all rices.
“Through this research, we’ve developed a calibrated DNA-based molecular clock that maps when divergences in the rice genome have occurred,” Professor Henry said.
“Few biological systems are as well described as rice now is.”
The paper detailing oucomes of the research into the genomes of domesticated and wild rice species is published in Nature Genetics. DOI: 10.1038/s41588-017-0040-0