Ancient Persian wheat: link to durums for saline cropping

Harvesting the salt secrets of the ancient world: Rana Manns with (R) the ancient wheat race crossed with Wollaroi (in front) to make the F1 generation cross plants that exclude salt from their roots.

A new salt-tolerant wheat could open up thousands of hectares of mildly salinity-affected cropping country to premium-quality durum production, according to GRDC-supported researchers.

Salt-tolerant plants have roots that prevent salt (sodium) from getting to the rest of the plant. Such plants are known as "excluders".

CSIRO research into salt tolerance is led by plant physiologist Rana Munns. Dr Munns' conventional test for salt tolerance is to grow plants under saline conditions in a hydroponic system, then measure the sodium level in the leaves.

If this is low, the plant must be an excluder and is selected for use in conventional backcrossing. The CSIRO team is now looking for molecular markers which could lead to a molecular probe for the exclusion gene.

NSW Agriculture wheat breeder Ray Hare obtained durum ancestors from the Australian Winter Cereals Collection. Some of these were 'excluder' land races from the Middle East that had developed on the salty soils of ancient Persia. In a fruitful collaboration, these were identified by the CSIRO technique and the researchers have been crossing this trait into modern durum lines. This should result in some tolerant lines in five to 10 years.

Dr Hare feels that the new varieties should help growers whose paddocks are mildly affected by salt, especially in drier years when salt is concentrated. Developing salt-tolerant wheat is expected to open up thousands of hectares of new country to durum production, and that could just be the start.

Contact: Dr Ray Hare 02 6763 1232