Drought proof barley a win for the industry

PLANT root research has given the barley industry a win, with the discovery of a gene that makes certain varieties more drought-tolerant. 

The Grains Research and Development Corporation (GRDC) has been funding a lot of work in sorghum, looking at the trait “stay green”.

Stay green has had a big impact in the sorghum industry as it helps to prolong the filling period under dry conditions in Queensland and NSW.

A key component contributing to stay green is a deeper root system.

With the research showing great promise in sorghum development, University of Queensland’s Lee Hickey said they started applying the research to barley and within 12 months, they’d discovered a major gene controlling the root angle of barley varieties.

The gene process determines the direction of barley’s root growth, with some varieties growing at a narrow, elongated angle.

Dr Hickey said this narrow root system allowed the plant to access out-of-reach water, deep within the soil and still continue to fill grain under dry conditions.

The narrow root system varieties would thrive along the east coast of Australia, where deep soils hold a lot of water.

Since identifying the benefit of the narrow root system, Dr Hickey said they’d been working on experimental populations.

Through access to breeding material from the Northern Region Barley Breeding program, the researchers were able to analyse three years of data for yield trials conducted in NSW and Qld.

Dr Hickey said they split breeding populations based on the root gene and found the breeding lines with narrow roots had a yield advantage of about 10 per cent in 16 out of 20 sites.

There was no yield advantage found in the remaining four sites, although Dr Hickey said there was no yield loss from growing the narrow roots system.

Despite the fact the narrow root systems only slightly improve a plant’s ability to access water, the small amount of extra water can make a big difference to the filling period and thus, yields. 

Dr Hickey said identifying and planting barley varieties with the gene was more about an insurance mechanism in variable seasons.

“If we can have these traits built into varieties and the season turns pear-shaped, we have an in-built insurance because the barley could access a little more water to continue filling grain,” he said. “That way, instead of having a loss that year, growers could break even or still even make a profit.”

Dr Hickey said they knew the gene was in several varieties so this year, they would look at how the gene interacted with traits above ground responsible for water use throughout the season.

“We’re going to marry all this information up with the root systems to better understand trait combinations.”