NSW Department of Primary Industries senior principal research scientist, Harsh Raman, said the study has unlocked the genetic make-up of canola to characterise major and minor genes resistant to the fungal pathogen Leptosphaeria maculans, which causes blackleg disease.

“Finding new sources of resistance, particularly resistance which is controlled by minor genes, is extremely important to the canola industry,” Dr Raman said.

“Blackleg disease can cause up to 80 per cent yield loss in canola - in Australia, France and Canada resistance has been broken down in some canola varieties due to the emergence of new races of the blackleg pathogen.

“Significantly for local canola growers, the study revealed new sources of blackleg resistance which were either resistant to the pathogen or had low levels of blackleg.”

Researchers used 18,804 DNA markers in a genome-wide association study to identify genes associated with both major and minor resistance in canola.

Several genes for resistance were mapped on the canola chromosome using molecular markers, which will assist the incorporation of a combination of genes to develop canola varieties with durable resistance to battle blackleg attack. Researchers used different races of blackleg fungus collected across Australian canola growing sites.