Researchers at Institute of Agriculture, The University of Western Australia (UWA), are supporting WA wheat breeders and ultimately growers by characterising the genetic and physiological traits of wheat that enable it to tolerate high concentrations of aluminium, manganese and iron.
With funding from the Australian Research Council (ARC) and the Department of Agriculture and Food WA (DAFWA), Dr Hossein Saberi and Professor Zed Rengel of the School of Earth and Geographical Sciences and Institute of Agriculture, UWA, have developed screening techniques for assessing the tolerance of different wheat varieties to ion toxicity.
Dr Saberi said that with more than 2.5 million hectares of acidic soils in cropping areas of WA and up to 1.7 million hectares of soils that are periodically waterlogged, conditions are created that allow ion toxicity to occur, reducing wheat yield and quality.
According to the Australian National Resources Audit in 2006, transient waterlogging affects one in four farms in the WA grainbelt, causing up to 70 per cent yield loss in extreme cases.
"Waterlogged soils are associated with a chemical process which increases iron and manganese ion levels beyond plant nutritional needs, leading to toxicity and poor plant growth," Dr Saberi said.
"Acid soils are associated with increased concentrations of aluminium ions, which are also toxic to plants."
Professor Rengel indicated that the identified variation will help with understanding the genetics and physiology of wheat tolerance to ion toxicity and characterising field sites for future breeding trials.
The group has already identified useful variation for iron and manganese toxicity tolerance among wheat breeding lines.
Robin Wilson, Senior Wheat Breeder at wheat breeding company InterGrain, a joint venture of DAFWA and the Grains Research Development Corporation, said the ion toxicity project would provide valuable information to growers on the reaction of traditional and new varieties to toxicity.
"It will also provide breeders with knowledge of wheat germplasm tolerant to ion toxicity and therefore traits which could be passed on through breeding," he said.
"Further, identifying new lines with varying levels of ion toxicity tolerance will enable researchers to define regions of WA where it occurs and gain a clearer picture of how it can affect wheat growing.
"Another desirable outcome of establishing tolerance to ion toxicity is a better understanding of how wheat copes with transient waterlogged conditions and this will help to develop future breeding strategies," Mr Wilson said.
20 Aug 2008
“Ion study may lead to bigger yield” http://www.news.uwa.edu.au/mar-2008/uwa-researchers-ion-out-wheat-toxicity-issue