benefits of foliar micronutrients on cereals in a low rainfall zone environment
The aim of this project is to determine the requirements and benefits of a foliar application of micronutrients in a low rainfall environment of the Northern Agricultural Region (NAR). The outcomes of this project aim to address and improve grower understanding of micronutrient management using decision support tools, such as plant testing; on farm productivity due to the timely application of foliar micronutrients, and; positive economic return through the improvement of grain yield and quality.
Grains Research and Development Corporation (GRDC)
Project lead organisation
CSBP and Murdoch University
The history of nutrient management research and development in Western Australia has focused largely around macronutrients nitrogen (N), phosphorous (P), and potassium (K) due to the greater natural uptake demand from crops. Previous research has identified that micronutrient requirements for normal crop growth are small (Bell & Dell, 2008). Due to the disparity in nutrition priority within our crop systems, disproportionate gaps in research between macro- and micronutrients widens. The lack of appeal in research, development, and extension (R, D & E) in this area is underpinned by the lower usage of micronutrients in crop production (Bell & Dell, 2008).
Progressive increases in crop yields through improved varieties and agronomic advances are common in many farming systems, and in the past have seen immense and rapid economic gains (10-20%). However, the implications of the ongoing demand for crops that yield higher, rotations that are more intensive, expansion into marginal land where nutrition is limited (Bell & Dell, 2008), and rapid decline in adequate growing season rainfall in the medium to low rainfall environment, has raised a growing concern around micronutrient management. The increased prevalence in deficiencies, identified by plant testing and paddock observation, begs the question about why these deficiencies are emerging where they did not previously limit crop growth, and what strategies or practices might be needed to manage such deficiencies in the future.
Previous trial work conducted by CSBP has shown up to 50% reduction in wheat yields from manganese (Mn) deficiency, and a further 80% reduction in yields due to copper (Cu) deficiency. These considerable losses in yield and the adverse effects on grain quality are accountable for financial losses in the vicinity of $150 – $240/t at a $300/t grain price. It has been identified by Brennan and Bell (2016) that there was a 15-30% increase in yield with the addition of micronutrients Mn and molybdenum (Mb).
A recent Liebe Group survey, conducted at the Liebe Crop Updates in March 2017, indicated that there was strong interest among growers to know more about how micronutrients are limiting production, and ways in which to manage micronutrient availability effectively and economically. The survey captured grower’s interest for a greater understanding of specific micronutrients with a 63% response rate linked to more knowledge around zinc (Zn), 59% for Mn, and 41% for Cu. These results have also been supported by the GRDC Regional Cropping Selections Network (RCSN) combined meeting in March 2017, with micronutrient deficiencies, sources, and efficiency ranked as the number one priority in the Kwinana West Port Zone.
Outputs from this two year project will include:
A literature review to determine current research knowledge and background information relating to micronutrient management.
A plant sampling survey, comprising of 100 kits containing four samples each, distributed to growers throughout the NAR. The large data set will provide spatial representation of the affected area, allowing the main focus of the project to accurately identify the micronutrient deficient areas of impact.
Interpretation and summary of plant sample survey data, identifying areas of deficiency and responsiveness. Those sites with identified micronutrient deficiencies (Zn, Cu, or Mn) will be subject to consideration for small plot trials in year two.
A grower survey, to determine the specific area and scale of impact of micronutrient deficiencies and management in the region.
In-season on-farm demonstrations.
Small plot strip trials, at sites selected based on the plant sample survey data.
Results and Reports
This project was funded by GRDC.