WHEAT breeders can now more easily select cultivars resistant to two of Australia’s most damaging wheat diseases - yellow spot and septoria blotch thanks to a research breakthrough.
Work at the Australian Centre for Necrotrophic Pathogens (ACNFP), in conjunction with a US-based research team has made valuable advances in cloning and sequencing a gene associated with the diseases.
Yellow spot is one of the most damaging wheat diseases in Australia, causing current annual losses of $212 million nationally.
Septoria is another major problem, causing national losses of $108 million.
A team led by geneticist Justin Faris of the Cereal Crops Research Unit in the United States Department of Agriculture’s Agricultural Research Service, has cloned and sequenced the gene for yellow spot necrosis 1 (Tsn1).
Tsn1 is the protein produced by susceptible wheat cultivars which helps yellow spot and septoria to infect the leaves.
ACNFP director Richard Oliver said ACNFP had identified some wheat cultivars containing a genetic marker previously used to identify susceptible lines, but which did not react to the diseases.
“This was a small but significant step in cloning the Tsn1 gene,” Professor Oliver said.
“Cloning the gene not only means we understand how these two pathogens cause disease, it also means we can give breeders more versatile tools to help them select resistant lines.
“Having the Tsn1 gene cloned means breeders can add a so-called ‘perfect marker’ into their breeding program.
“Previously there was a discrepancy between the old marker and disease resistance.
“The use of the new ‘perfect marker’ means it will be easier to eliminate the susceptible cultivars and we should be well on the way to slashing losses to these diseases.”
