Source: Western Australia, Department of Primary Industries

Researchers at Western Australia's Department of Agriculture and Food are identifying elite germplasm to help breed new waterlogging tolerant wheat varieties.

The methodology from the project is also being used to develop waterlogging tolerant wheat varieties in India with three Indian research institutes as part of a projected funded by the Australian Centre for International Agricultural Research (ACIAR).

The department is mid-way through the four year collaboration with the University of Adelaide to identify suitable material that is tolerant to waterlogging and associated micro-element toxicities, which also has improved disease resistance.

Up to 40 percent of agricultural land in WA can be affected by waterlogging, which can significantly reduce crop yields.

Department research officers Tim Setter and Irene Waters recently visited the University of Sydney's Plant Breeding Institute (PBI) at Cobbitty, NSW, where plants from the trial were screened for resistance to leaf, stem and stripe rust.

A total of 1200 plants with high waterlogging and aluminium tolerance were tested, of which only one percent had acceptable rust resistance.

Dr. Setter said although the selection pressure was extreme, there was still some useful material that could be used in the next season's trials.

"New South Wales has had an extremely wet year, which resulted in extreme stripe rust infections," he said.

"The lines tested were developed from the WA variety Tammarin Rock and a doubled haploid breeding line, both of which have good waterlogging tolerance.

"The best performers will now also be used in a backcrossing program using parents from the University of Sydeny PBI to improve disease resistance. Lines will be screened next year at the waterlogging tolerance screening facility at Katanning."

Waterlogging tolerance screening involves sowing 5,000-10,000 pots per year containing different soil types planted with more than 400 wheat and barley breeding lines in a 200 meter square pond at the department's Great Southern Research Institute at Katanning.

The seedlings used include commercial varieties, local breeding lines, as well as germplasm from India.

Dr. Setter said an interdisciplinary approach was required to develop waterlogging tolerant wheat varieties.

"Waterlogged soils have low levels of oxygen, which affect the plants' capacity to exclude potentially toxic elements like boron, aluminium and sodium. Waterlogging also increases the availability of other elements in the soil like iron and manganese," he said.

"The challenge for plant physiologists and plant breeders is to develop germplasm that is not only waterlogging tolerant but also tolerant to micro-element toxicity and has disease resistance.

"Plant breeding is a slow process but significant gains are being made by research in the target environments."