Southern NSW and the south of Australia is expected to experience more frequent droughts in the years to come.
Scientists are working on solutions for the drying and warming climate, experimenting with genomic sequencing to offer grain breeds that access deeper soil moisture.
CSIRO chief research scientist Dr Greg Rebetzke is working on the development of a longer protective sheath of the first leaf (coleoptile). The coleoptile guides a shoot from a seed to the surface. The longer it is, the greater the emergence potential from deeper in the soil.
Dr Rebetzke is using climate modelling to improve the performance of crop varieties suited to future climate conditions.
His team sourced global wheat genetics from areas like Europe and Russia to establish what suits Australian conditions.
“We‘ve identified other drawing genes that also reduce plant height and give us high yields. Early vigour represents early growth,” Dr Rebetzke said.
He said barley is valued given its tolerance to drought.
“A large part of what barley does is it shades the soil surface and most of the water the crop uses comes as rainfall. If you’re not shading the surface then the sun and wind evaporate most of that water away.”
Estimates suggest as much as 60% of the rain that falls is evaporated away from our wheat crops because our crops aren’t vigorous enough to protect it.
Learning from barley, he’s developed a greater leaf area with increased early vigour.
“By doing so, we improve the capacity of our crop to shade the soil’s surface. It’s more drought tolerant because seed is more water-efficient,” he said.
A planting depth of 10cm or lower offers seed access to stored deeper soil moisture.
Agrowdrill seeders equipped with a 425 coil tyne assembly and baker boot achieve this. An extended deep baker boot option plants at 12.7cm (or 5 inches).
To ensure wheat growers can take advantage of these new lines when they become available, Grains Research and Development Corporation (GRDC) is investing in two years of on-farm trials.
The small plot trials are being conducted on a range of soil types in Western Australia’s low to medium rainfall zones and are being led by Michael Lamond and Craig Brown, of SLR, which is part of the Synergy Group.
Josh Johnson, GRDC manager agronomy, soils and farming systems – west, said the new trials will focus on the relationship between the long coleoptile trait and agronomic factors including time to emergence, soil temperature and planting depth, as well as the combined effect of these traits on crop establishment.
“This work will also facilitate grower and adviser discussions on agronomic, nutritional, farming systems and crop protection considerations – to help guide future research,” Mr Johnson said.
“The development of these technologies is also being driven by increasing farm sizes, higher temperatures at the end of the growing season and the need for growers to complete seeding within the optimum sowing window.”