A physiological test that simply and quickly identifies plants with the gene for stress tolerance has been developed by Jim Morgan of NSW Agriculture.
It involves screening pollen from flowering plants. The test is very effective, while being cheap, portable and simple enough to do on the back of a ute, according to durum wheat breeder Ray Hare.
Water stress in plants occurs when transpiration rates mean that water lost from the leaves cannot be replaced fast enough — either there is not enough root area to absorb the water, or there is not enough water in the soil. This results in wilting.
Plants vary in their ability to tolerate water stress, a characteristic being closely examined by the National Durum Wheat Improvement Program based at NSW Agriculture's Tamworth Centre for Crop Improvement. Stress-tolerant plants are able to grow better during the heat of the day, or for a longer period. This leads to higher yield, adding to the economic return to the grower.
The Tamworth team uses Dr Morgan's test for rapid screening followed by conventional backcrossing. Yield improvements of up to 15 per cent have resulted.
Dr Hare said the natural diversity in wheat allows many characteristics to be selected without the need for gene technology to introduce the gene from another species.
The research has been so successful that Dr Hare reports that Australia is among the world leaders in durum wheat breeding, and many of our advanced breeding lines have been sent to the International Centre for Agricultural Research in the Dry Areas (ICARDA) in Syria for use in collaborative breeding programs.
Program 1.6.1 Contact: Dr Ray Hare 02 6763 1232