A gene that causes barley plants to send their roots down, rather than sideways, had been identified for the first time. It's identification could help increase the capacity of the crop to cope with drought, in a world where rain will be increasingly unreliable.
“Even in a drought, there is water deep underground and to be able to breed plants with the type of root system to access this water means growers can maintain barley yields in drought conditions,” said Dr Lee Hickey of the University of Queensland in a statement.
Alleles, specific forms of genes that cause plants to grow deep but narrow roots, have been identified in rice, maize, and sorghum, Hickey told IFLScience, but had not been found in barley prior to his team’s research. Since barley is not only the world’s fourth largest cereal by volume of production, but one often grown in drought-prone areas, a mechanism to allow farmers to minimise losses in bad years could be very important.
Hickey said that prior to the work of Hannah Robinson, a PhD student in his lab, little was known about barley’s root architecture. “We followed in the footsteps of the people who studied other crops, but we also introduced something new,” he told IFLScience.
It seems an obvious move in hindsight, but Hickey’s team believe they are the first to plant barley in transparent pots. “We plant the seeds around the edge and can see the root architecture in a week,” Hickey said. Comparing this to DNA markers allowed Hickey and Robinson to match the root shape to the allele responsible in less than a year.
These clear pots have allowed Hickey's team to study the roots of barley and wheat like never before. Lee Hickey.
Besides the capacity to access deeper water, the deep but narrow structure stops a barley plant wasting energy competing with its neighbors, a valuable thing in a plant usually grown as a monoculture.
Hickey thinks that plant scientists have spent too much time focusing on what is above ground and visible. “The roots are really untapped,” he said. Moreover, many researchers haven’t put enough effort into connecting lab work with what occurs when the crops they study are grown in the field.
Hickey hinted to IFLScience that the announcement of this discovery, to be published in The Plant Genome, is just the prelude to an even bigger breakthrough he expects to release soon.
Meanwhile, this work is important on its own. Hickey said the allele already exists in widely grown varieties, adding, “We didn’t have to go back to wild types.” However, now that its identity has been revealed it can be combined with other attributes to create a product that can be sown in years when drought conditions are anticipated or locations with highly seasonal rainfall.
The discovery could be a step towards providing seeds matched to the soil and climate conditions of individual farms. Hickey has identified commonalities with the genes that play the same role in other cereals, which may assist with further work in other species, particularly wheat.
Hannah Robinson uses a "Greenseeker" to measure how green the barley is. QAAFI.