FOR Australian wheat breeding specialist Richard Trethowan, having access to the largest wheat genebank in the world - through the CIMMYT International Maize and Wheat Improvement Centre research organisation in Mexico - is akin to giving a child free rein in a lolly shop.
The University of Sydney Plant Breeding Institute professor, who was a wheat breeder at CIMMYT for 13 years, now heads a team of Australian wheat breeders who travel to Mexico every two years to select potential breeding lines for the Australian wheat industry.
It’s a trip Australians have been making since the first wheats from CIMMYT were introduced to Australia in 1973.
Today it is a fine-tuned process run under a partnership agreement called CAIGE which links Australia not only to CIMMYT but to another major wheat centre, ICARDA, in the Middle East.
On a recent selection trip to Mexico which coincided with the Borlaug Summit on Wheat for Food Security, Professor Trethowan and the team chose promising lines with traits they believe the Australian wheat industry needs.
“We are looking firstly for yield. Beyond that we are looking for white grained, short statured types, a range of resistance to diseases, and also diversity,” he said.
“We look carefully at the pedigrees of the different lines. We are after pedigrees that are very different to what we have in Australia because that is new diversity.
“If we pick up a rust-resistant line in the field and take it back to Australia and it may have the same genes for resistance as the lines we currently have we are not going to make a lot of progress.
“But if we pick up a line that has a very different pedigree and origin there is a much higher probability it will bolster the defence against rust diseases in Australia.”
The lines that make it through the selection process will be brought to Australia where they will be evaluated by breeders and provided to breeding companies to cross with other lines.
Professor Trethowan said the reason CIMMYT didn’t release them directly was because of quality issues.
“Here at CIMMYT the focus is on the developing world where they need volume in their wheats. Most people there turn CIMMYT wheats into flat bread so they don’t need premium quality,” he said.
“In Australia we have a segmented export market and distinct quality classes.
“The basic quality you find in the CIMMYT wheats doesn’t fit those quality classes, so there needs to be a cycle of breeding that takes advantage of the yield and disease resistant traits of the CIMMYT material and the quality of the Australian material. That is what the plant breeders do in Australia.”
Neil Lyon travelled to Mexico with the assistance of the Crawford Fund and the Department of Foreign Affairs and Trade’s Council on Australia Latin America Relations.