Scientists at the Australian CSIRO Plant Industry (Commonwealth Scientific and Industrial Research Organization) have discovered two genes, called Nax1 and Nax2, that could be used to develop salt-tolerant wheats. Nax1 exudes sodium (Na, geddit?) from the leaves while Nax2 excludes it from the roots. The two genes appear to come from an ancient type of wheat, Triticum monococcum, that was accidentally crossed into a modern durum wheat line about 35 years ago. Rana Munns, the team leader, said the discovery was an amazing stroke of luck.
We screened a hundred durum wheats from the Australian Winter Cereals Collection at Tamworth, which contains tens of thousands of wheat types. Highlighting the fact that the science of plant breeding sometimes relies on an element of good fortune, we were lucky to find the durum variety with the ancient genes straight away, otherwise we might have been looking for years.
The search was motivated by the knowledge that 6% of the world’s arable areas are affected by salinity.
Personally, of course, I’d like to know more about that accidental cross that put T. monococcum genes into a modern bread wheat, but details are not forthcoming.
Article: Physiological Characterisation of Two Genes for Na+ Exclusion in Durum Wheat: Nax1 and Nax2.