Australia
June 6, 2006

The Crop Doctor, GRDC
The Crop Doctor is GRDC Managing Director, Peter Reading

Biotechnology is being harnessed in a project aimed at producing frost tolerant wheat and barley varieties faster.

Working with 3000 wheat varieties and 5000 barley varieties collected from an area stretching from the Himalayas to the Middle East, CSIRO Plant Industry researcher Dr Ben Trevaskis is screening for variations to the VRN1 gene, the one responsible for determining the flowering date in wheat and barley. His project is supported by growers and the Australian Government through the Grains Research and Development Corporation (GRDC).

Dr Trevaskis says there is an enormous variation in alleles of the VRN1 gene. Initially the gene is responsible for determining whether the wheat or barley variety will flower in spring, or over-winter before flowering. Breeders have been working with it for generations to make selections for varying flowering times.

In fact, Dr Trevaskis says that William James Farrer, developer of the Federation wheat variety released in 1903, probably introduced the gene into Australia when he was making his first crosses, while in the 1970s Dr Albert Pugsley pioneered the work of introducing variations of the gene into varieties with similar backgrounds. Dr Pugsley was able to work with five different variations; however developments in biotechnology are allowing researchers like Dr Trevaskis to take using a diagnostic approach to identify more variations from thousands of varieties.

Dr Trevaskis aims to produce not only varieties with a range of flowering times but to make use of another attribute of the gene, frost tolerance.

Breeding groups working to identify vegetative traits responsible for frost tolerance have traced them back to the VRN1 gene. Variations of this gene influence not just the time of flowering, but frost tolerance. It's natural - cereal varieties have developed in climates ranging from extreme cold to extreme drought. Variations of this gene are one of the critical factors in that acclimatisation. Dr Trevaskis and his team aim to make selections leading to varieties with a range of flowering times that are also frost tolerant. It means that, even in high frost risk areas, growers will be able to enjoy the flexibility of varieties with a range of flowering times.

The key to this work is a technique called 'eco-tilling'. In essence it means looking for variations from the DNA sequencing of different varieties. Dr Trevaskis says that we have already identified and understood the properties of a large number of variations of the VRN1 gene - he's looking for the as yet unidentified variations.

Screening 8,000 varieties is a daunting task but modern technology will allow the team to screen up to 100 varieties a day looking for those unidentified variations.

Once isolated, the plan is to introduce the selected alleles (variants) of the VRN1 gene into a common parent that is an already established variety. 'Sunstate' has been chosen as the wheat variety and discussions are still underway to identify suitable malting barley varieties.

Dr Trevaskis says his team will be able to turn this material over to plant breeders working in the field so that they can see the effect of the variations in a known variety under field conditions, and make their selections from there. In effect they will have already completed about half of the normal backcrossing needed to produce a new variety.

Better yet, Dr Trevaskis says that it is possible to identify perfect markers associated with selected variations. That will speed up the identification of material containing the selected variations of the VRN1 gene.

The estimation is that initial screening of the huge amount of collected material will take three years and the incorporation of selected material into existing varieties another two or three. It's a clear case of biotechnology speeding the process of developing new and better varieties through conventional methods and demonstrates the GRDC's commitment to bring better varieties to growers faster.

For more information contact Dr Ben Trevaskis on (02) 6246 5045 or email ben.trevaskis@csiro.au