Research puts spotlight on micronutrients
New research aims to deliver clear guidelines to Western Australian grain growers to help them manage micronutrient (trace element) disorders in their crops, particularly wheat.
Funded by the Grains Research and Development Corporation and led by the Department of Agriculture and Food (DAFWA), the three-year project will address concerns that micronutrient deficiencies may be increasing in the WA grainbelt.
Murdoch University’s Richard Bell, who is one of the researchers involved in the project, said that despite crop plants requiring only small quantities of micronutrients, inadequate supplies could reduce growth and crop yields and lead to nitrogen and water being wasted.
He said the new WA research, led by DAFWA’s Ross Brennan, would focus on copper (Cu), zinc (Zn), molybdenum (Mo) and manganese (Mn).
“While decision support packages are common for the macronutrients nitrogen and phosphorus, there is some uncertainty surrounding the management of micronutrient deficiencies,” Professor Bell said.
“There is increasing concern that micronutrient supplies from the soil may be becoming depleted by current cropping systems that are more productive, intensive and reliant on supplies of nitrogen and phosphorus fertilisers.”
Professor Bell said micronutrient guidelines developed under the project would be based on current data and relevant to the agronomics and economics of modern cropping systems.
“Existing management packages designed to maintain micronutrient levels in the soil were developed 40 years ago and may no longer be appropriate,” he said.
Professor Bell said growers in some WA cropping areas had been concerned in recent seasons that copper deficiencies may be limiting crop production.
“However, copper deficiency symptoms are similar to those caused by frost damage and there is some confusion over what factor is causing the problem,” he said.
“A new and associated research project aims to clarify whether micronutrient additions, including copper, will increase crop tolerance to frost.”
Professor Bell said molybdenum deficiencies were especially apparent in soils with a pH below 4.5, as the micronutrient was unavailable to crops in these highly acidic soils.
Information about micronutrients in Australian cropping systems is available in the GRDC Micronutrients Fact Sheet at www.grdc.com.au/GRDC-FS-CropNutrition-Micronutrients.
Caption: Wheat with adequate zinc, left, compared with zinc-deficient wheat. Photo by Matt Witney, Dodgshun Medlin.
Richard Bell, Murdoch University
08 9360 2370
Natalie Lee, Cox Inall Communications
08 9864 2034, 0427 189 827
GRDC Project Code DAW00239, UMU00045