FARMERS are one step closer to having salinity and drought tolerant-barley varieties thanks to a study by University of Adelaide researcher Caitlin Byrt.
In collaboration with GRDC-funded researchers and with a research team from the James Hutton Institute, Scotland, Dr Byrt has been studying genes from wild relatives of barley crops to find what makes them so tolerant to saline conditions.
With about 360,000 hectares, or 2.3 per cent, of the state affected by dryland salinity, Dr Byrt aims to cross the traits into modern varieties to boost yields of crops growing in saline conditions.
“Dryland salinity has significant impacts on SA’s productivity and quality of our crops and pastures,” she said.
“The Upper South East is particularly affected by salinity, with about 200,000ha severely affected.”
Dr Byrt said about 50pc of potential grain yields were often lost to soil salinity, but some wild relatives of barley only suffered an 8pc reduction in grain yield when growing in very saline conditions.
The research identified a key gene in barley that influences the amount of sodium that accumulates in the leaves in saline conditions.
“The gene we are studying in barley encodes for a protein that transports sodium,” Dr Byrt said.
“The barley plants can use this protein to help prevent salt building up in the leaves.
“If we can understand the difference between plants that are at the extremes of tolerances to saline environments, then we can use this information to engineer cropping systems that are productive, despite high salt concentrations in soil or irrigation water.”
Dr Byrt said one of the findings in the present research was similar to her previous GRDC-funded work looking at a population of wheat relatives that also related to the accumulation of salt in leaf tissues in saline conditions.
“Interestingly, although the influence of these genes of interest in the plant is similar for wheat and barley, when we test the function of the genes in the lab, they have different features,” she said.
The next phase will endeavour to find out how root composition influences the salt and water uptake.
Dr Byrt said a variety of root tissue sections would be sampled at an early germination stage and studied under the microscope to get an idea of the different anatomy of the roots, along with their composition.
“Then we will be able to narrow down material that is at different extremes and how that influences salt and water uptake and the tolerance of salinity,” she said.
Dr Byrt said the other aspect of the research included how the genes were influencing salt concentrations in the grain.
“This could influence brewing, such as the flavour of beer,” she said.
The barley investigation was funded for a year by the GRDC’s sponsorship of the grains category of the annual Science and Innovation Awards for Young People in Agriculture, Fisheries and Forestries.
But Dr Byrt has recruited a PhD student, who will continue to work on the project for three years.
Wheat research unlocks greater yield potential
AS A self-confessed “foodie” and as an environmentally-conscious person, Caitlin Byrt decided it would be worthwhile contributing time to crop science research.
The University of Adelaide postdoctoral researcher said watching the trajectory of the global food situation and the need to produce sufficient, high quality food, led her to becoming a researcher.
Her previous GRDC-funded project with colleagues from CSIRO and the University of Adelaide led to a 25 per cent increase in durum wheat grain yields in saline soils, with markers for the gene of interest distributed to more than 18 countries.
The results were achieved in NSW on field sites where the average soil salt content was about 170 millimolars sodium chloride.
The genes from the wild relatives were moved into durum wheat variety Tamaroi, by traditional crossing methods, which means they are suitable to be cropped in SA.
“We studied a population of wheat relatives and found variation within the population for how much salt accumulated in leaf tissues in saline conditions,” Dr Byrt said.
“We used lines that were very good at keeping salt out of the leaves to create a mapping population so that we could determine which genes influenced the leaf sodium accumulation.”
Two genes were identified and further studies have addressed how they function.