The rice, which grows in the billabongs in the North, could make it possible to breed disease resistance and climate adaptation into modern-day rice production, say University of Queensland (UQ) researchers who have mapped its genetic family tree.
"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," explained Professor Robert Henry from the Queensland Alliance of Agriculture and Food Innovation.
“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,” he said.
These hardy qualities of Australian wild rice could greatly aid in boosting global rice production, and therefore aid in promoting food security around the world.
Health benefits
Moreover, Prof Henry said the Australian wild rice has 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 rice types, and a higher amylose starch content.
"The higher the amylose content, the longer the rice takes to digest," said Prof Henry.
"This potentially offers more nutrition to our gut microbes, in the same way high-fibre foods do."
Prof Henry noted that human trials were needed to confirm the health benefits but the chemistry suggested this was the case.
Ancient origins of the wild rice
The research shows 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.
Prof Henry said the study provided a comprehensive insight into the “rice family tree”, and confirmed that Australian wild rice was the most directly-related species to the ancient ancestor of all rice species today.
"Through this research, we've developed a calibrated DNA-based molecular clock that maps when divergences in the rice genome have occurred," said Prof Henry.
"Few biological systems are as well described as rice now is."
Rice is the most widely-consumed staple food for much of the world's population, especially in Asia and many parts of Latin America. It is the third-largest agricultural crop worldwide.
Source: Nature Genetics, 2018
DOI: 10.1038/s41588-018-0040-0
“Genomes of 13 domesticated and wild rice relatives highlight genetic conservation, turnover and innovation across the genus Oryza”
Author: Joshua C. Stein et al