THANKS to the Sir Eric Smart Scholarship for Agricultural Research, two fourth year agricultural science honours students at The University of Western Australia have ‘buried their heads in the sand’ while attempting to unlock some of the keys to improving or ameliorating poor WA soils.
Esperance farmer’s son Gregory Campbell’s project, ‘Effectiveness of compost and gypsum as a soil amendment and their influence on mycorrhizal colonisation’, supervised by Winthrop Professor Lyn Abbott, found that compost and gypsum amendment did not significantly improve crop growth in the single growing season studied.
“However, there was a significant, but inconsistent effect on mycorrhizal colonisation from the gypsum application,” Mr Campbell said.
“While gypsum is commonly used on WA agricultural soils, applying compost is a relatively new concept in broadacre agriculture, although commonly used in horticulture.”
Mr Campbell’s father, David, who is in the process of trialling the production and application of compost on his two farms, ‘Karranga’, west of Esperance and ‘Karingal’, north of Esperance, will now test his son’s hypotheses that soil amended with compost will: have better cation exchange capacity. have higher mycorrhizal root colonisation after one season, compared to control and inorganic fertilised soils.
Gregory Campbell said his father would also test if higher rates of compost would have an even greater influence on the microbial and fungal population.
Professor Abbott said that practical on-farm testing and potential subsequent commercial adoption of research by such capable young students from UWA’s Faculty of Natural and Agricultural Sciences, with support from UWA Institute of Agriculture, was a positive outcome.
Supervised by Winthrop Professor Zed Rengel, Darkan farmer’s son, Paul South, assessed whether or not lime was a better soil ameliorant than gypsum with respect to alleviating aluminium toxicity stress in susceptible wheat.
“With one third of WA agricultural soils affected by sub-surface acidity and with this very likely to increase soluble aluminium, which is toxic to plant root growth, the issue was worth assessing from economic and agronomic perspectives,” Mr South said.
Soil acidification in WA affects about 1.6 million hectares of arable cropping land and annually costs $70 million, due to crop yield losses and methods used to reduce it.
Mr South’s Sir Eric Smart Scholarship supported honours project compared the effectiveness of genetic and chemical (lime and gypsum) strategies in resolving the aluminium toxicity issue.
While identifying that a combination of lime and aluminium tolerant crops was the most effective, Mr South recommended further comparisons between genetic and chemical options.
“The next stage of this research needs to apply science and economics to determine what’s most likely to be adopted by farmers, because the most effective strategy may not be the most economical and therefore may have limited adoption by farmers,” he said.
UWA Institute of Agriculture Director, Winthrop Professor Kadambot Siddique, explained that the late Sir Eric Smart was a pioneer cereal producer in light land areas around Mingenew and was once the world’s largest individual wheat grower.
Upon his death in 1973, Sir Eric showed his appreciation of science by endowing substantial funds to UWA and this was later supplemented by a gift from his son Peter.
“He wanted to see science improve agricultural production and the first allocation from the Sir Eric Smart bequest to UWA was to help lupin growers deal with manganese deficiency,” Professor Siddique said.
“Essentially, the Sir Eric Smart Scholarship encourages bright students in UWA’s Faculty of Natural and Agricultural Sciences to research ways of improving the productivity and profitability of wheat, barley, lupins or canola growing in the light soil types of WA.”
Sir Eric Smart came to WA in 1934 from South Australia with his life savings of 200 pounds to share farm at Watheroo. In 1949 he acquired Erregull Springs, Mingenew, a 10,000 hectare property. More than half the farm was light sand-plain country and it was there that he experimented with superphosphate and lupins to build soil fertility of the light land for cropping.
In 1950 grain production from Smart's properties set an Australian individual record of 102,000 three bushel bags (8200 tons). Production regularly increased, passing 500,000 bushels (13,400 tons) in 1967.
Gregory Campbell and Paul South will work on their family’s Esperance and Darkan farms, respectively.