Dialling up wheat heat tolerance
HEAT stress costs the Australian grains industry $37 million each year in wheat alone. Grains Research and Development Corporation, with University of Sydney, InterGrain, Agriculture Victoria and the Western Australian Department of Primary...
HEAT stress costs the Australian grains industry $37 million each year in wheat alone.
Grains Research and Development Corporation, with University of Sydney, InterGrain, Agriculture Victoria and the Western Australian Department of Primary Industries and Regional Development, is investing in research to improve the heat tolerance of wheat varieties to maximise yield potential in warmer climates.
The $4 million project proposes to deliver a minimum of five adapted wheat pre-breeding lines with at least 10 per cent higher yield than the current highest yielding cultivars under heat stress during grain filling by 2026.
University of Sydney agricultural scientist Dr Rebecca Thistlethwaite said growers, especially in warmer climates, had expressed concern about heat stress impacting crops and the need for the grains industry to respond to a changing climate.
“Grower feedback is the main reason we do this type of work,” she said.
“Growers are facing a warmer, changing climate so it’s a no-brainer for us to respond to that as soon as possible.
“We’ve made it a priority to work on breeding better heat tolerance lines now, while we still have time to do it, because if we leave it too long, the industry will get stuck.”
Dr Thistlethwaite said the project had used a three-tiered approach to screen large numbers of materials, primarily in the field.
It starts with identifying genotypes that limit the effects of drought stress from field trials.
They are then placed in heat chambers in the field to see how they perform under heat shock and then any genotypes that maintained adaptation in the heat chambers are taken to glasshouses to be looked at in more depth.
The best lines are then crossed to produce new materials, and tested at 40 InterGrain sites to further evaluate their potential.
“These new lines will be enriched for heat tolerance at grain filling and delivered to wheat breeders with genomic information to aid selection and incorporation of tolerance into new varieties,” Dr Thistlethwaite said.
“We’re not producing lines that would fall over in a normal year but do well with heat pressure — we’re selecting to generate lines that will do well across all bases.”
