New salt-tolerant wheat may combat food shortages

London, Mar 12 (ANI): Scientists have created a new variety of wheat, which can tolerate salty soil and may help tackle threat to food production caused due to climate change.

A team of Australian scientists bred salt tolerance into a variety of durum wheat that showed improved grain yield by 25 percent on salty soils.

Using 'non-GM' crop breeding techniques, scientists from CSIRO Plant Industry have introduced a salt-tolerant gene into a commercial durum wheat, with spectacular results shown in field tests.

Researchers at the University of Adelaide's Waite Research Institute have led the effort to understand how the gene delivers salinity tolerance to the plants.

The research is the first of its kind in the world to fully describe the improvement in salt tolerance of an agricultural crop - from understanding the function of the salt-tolerant genes in the lab, to demonstrating increased grain yields in the field.

"This work is significant as salinity already affects over 20% of the world's agricultural soils, and salinity poses an increasing threat to food production due to climate change," said CSIRO Plant Industry's scientist Dr Rana Munns, who is the lead author of the study along with Dr Richard James.

"Salinity is a particular issue in the prime wheat-growing areas of Australia, the world's second-largest wheat exporter after the United States. With global population estimated to reach nine billion by 2050, and the demand for food expected to rise by 100 percent in this time, salt-tolerant crops will be an important tool to ensure future food security," said Dr Matthew Gilliham from the University's Waite Research Institute.

Domestication and breeding has narrowed the gene pool of modern wheat, leaving it susceptible to environmental stress. Durum wheat, used for making such food products as pasta and couscous, is particularly susceptible to soil salinity.

However, the authors of this study realised that wild relatives of modern-day wheat remain a significant source of genes for a range of traits, including salinity tolerance. They discovered the new salt-tolerant gene in an ancestral cousin of modern-day wheat, Triticum monococcum.

"Salty soils are a major problem because if sodium starts to build up in the leaves it will affect important processes such as photosynthesis, which is critical to the plant's success," Dr Gilliham said.

"The salt-tolerant gene (known as TmHKT1;5-A) works by excluding sodium from the leaves. It produces a protein that removes the sodium from the cells lining the xylem, which are the 'pipes' plants use to move water from their roots to their leaves," he said.

"While most studies only look at performance under controlled conditions in a laboratory or greenhouse, this is the first study to confirm that the salt-tolerant gene increases yields on a farm with saline soils.

Field trials were conducted at a variety of sites across Australia, including a commercial farm in northern New South Wales.

"Importantly, there was no yield penalty with this gene," Dr James said.

"Under standard conditions, the wheat containing the salt-tolerance gene performed the same in the field as durum that did not have the gene. But under salty conditions, it outperformed its durum wheat parent, with increased yields of up to 25 percent.

"This is very important for farmers, because it means they would only need to plant one type of seed in a paddock that may have some salty sections," Dr James said.

"The salt-tolerant wheat will now be used by the Australian Durum Wheat Improvement Program (ADWIP) to assess its impact by incorporating this into recently developed varieties as a breeding line."

Dr Munns said that the new varieties of salt-tolerant durum wheat could be a commercial reality in the near future.

"Although we have used molecular techniques to characterise and understand the salt-tolerant gene, the gene was introduced into the durum wheat through 'non-GM' breeding processes. This means we have produced a novel durum wheat that is not classified as transgenic, or 'GM', and can therefore be planted without restriction," she added.

The study has been published in the journal Nature Biotechnology. (ANI)