Cathrine H Ingvordsen1, Tina Rathjen1, David J Smith2 & Greg J Rebetzke1
1 CSIRO, Agriculture and Food, PO Box 1700, Canberra, ACT, 2601, http://www.csiro.au/en/Research/AF/Areas/Plant-Science, firstname.lastname@example.org,
2 CSIRO, Agriculture and Food, Private Mail Bag, Yanco, NSW, 2703
Weeds are estimated to cost Australian agriculture $4.3 billion a year. In Australia herbicide-resistant weeds are identified with increasing frequency, challenging current weed control methods. Competitive crop varieties are a little used weed control tool despite being low cost and easy to implement with other weed control approaches. Traditionally, Australian wheat varieties have not shown good early vigour, a trait representing more rapid leaf area development through wide leaves and greater biomass at stem elongation. Early vigour is a common mechanism of competition in natural plant communities and could be useful in managed farming systems. This paper describes a pre-breeding approach to develop Australian competitive wheat varieties. Overseas wheats with great early vigour were sourced and the vigour combined in one vigour-donor, which was crossed traditionally with adapted commercial varieties. The developed advanced breeding lines were assessed for agronomic parameters in rows in the field and then distributed amongst Australian commercial breeding companies. To date, ~5000 advanced main-season breeding lines have been distributed to Australian commercial breeding companies and evaluated by commercial breeders for uptake in their breeding programs. A further ~4000 advanced breeding lines including long-season types are under development for release in 2019-20. The feedback from commercial breeders on distributed advanced breeding lines has been positive.