MURDOCH, AUSTRALIA -- An international team of scientists from Australia and China announced the first chromosome-scale genome of a wild barley species, describing the breakthrough as a significant development in sustainable agriculture and yield improvements.

Led by researchers from Murdoch University and the Beijing Academy of Agriculture and Forestry Sciences (BAAFS), the study of the wild barley species Hordeum brevisubulatum - noted for its exceptional tolerance to alkaline and saline soils - is a significant advance in harnessing crop wild relatives (CWRs) to combat soil degradation and extreme weather events, the team said.

The study, published in Nature Plants, identified critical genetic adaptations, including the duplication of stress-response genes that enable efficient nutrient intake under alkaline stress. When overexpressed, these genes doubled in biomass and offered improved yields in harsh conditions. The team also discovered that a fungal-derived gene that was previously known for disease resistance was found to reduce oxidative stress in saline-alkaline environments.

Following these findings, the team developed a new hexaploid crop, Tritordeum (AABBII), by replacing wheat's 'D' subgenome with H. brevisubulatum's I genome. This new crop has exhibited a remarkable 48% increase in nitrate uptake and a 28% increase in grain yield under stress compared to conventional wheat, the researchers said.

"Our findings offer transformative potential for Australia's agricultural sector, particularly in regions like Western Australia and South Australia where there is significant dryland soil salinity," said Chengdao Li, director of the Western Crop Genetics Alliance and co-author of the study. "By breeding salinity-resistant grain crops, we can safeguard yields in drought-prone areas, reduce our costly reliance on fertilizers while maintaining productivity, and make a tangible step towards Australia's 2030 sustainability targets.

"Additionally, the extraordinary resilience of H. brevisubulatum's I genome equips us with genetic tools to future-proof staple crops against climate extremes, ensuring the competitiveness of our grains sector."

Australia is the world's top exporter of barley, while China is among the largest importers of the grain and an important buyer for Australia.

This study was a joint effort among scientists from Murdoch University's Western Crop Genetics Alliance, Murdoch University's Centre for Crop & Food Innovation, BAAFS, and other international institutions. The team assembled the high-quality genome of H. brevisubulatum, a perennial wild barley species native to saline-alkaline regions and re-sequenced 38 accessions across seven related species.