Managing micronutrient deficiencies in cropping systems of eastern Australia

This project will address these increasing concerns and speculation in a three pronged approach for all six micronutrients named in the tender (Mn, Zn, Cu, B, Mo, Fe) for all cropping regions in Australia except for those in WA. This project will liaise closely with a separate bid being prepared by Dr Ross Brennan of DAFWA to address issues in WA specifically, should that bid be successful. This project will produce clear guidelines for management of micronutrient disorders for the major crops in the southern and northern regions of GRDC based on existing knowledge which has been objectively tested for its relevance to modern cropping systems and modernised for current technologies and economic circumstances where necessary.


14 Oct 2016

Zinc trial - Wheat Wunkar 2015

Wunkar, South Australia, 2015

A range of delivery strategies for Zn were evaluated at this site, and these were assessed as responses in terms of shoot dry weights, grain yield, screenings and grain protein concentration. The nutrient concentrations in the YEBs were assessed as well.

The mean site yield was 1.8 t/ha, and there was a small (0.1 t/ha, p<0.05) response to applied Zn, even though the soil test was very low 0.14 mg/kg. The tissue response was large with YEB Zn concentrations increasing from 17 mg/kg with nil Zn to 31 mg/kg Zn with supplied Zn, There were no real trends in the delivery or formulation strategies although the best treatment was the low rate of fluid Zn applied at seeding.

Table Treatments applied and tissue test values at GS15 or GS30 or at least 14 days after foliar application.

Sulphate foliar spray (300g Zn/ha) Fluid at seeding (0.75kg Zn/ha)

Site selected on history of Zinc deficiency, results from an infield demo provided by Chris McDonough (Formally Rural Solutions SA). Area in paddock selected and sampled (first column of soil test results). [Zn] >0.3mg Zn/kg so site pegged and used for 2015 trial season.

Trial site summary:
Plots of 20m x 2m were sprayed with treatments. There were 9 treatments and 4 different product groups (sulphate, EDTA chelate, lignosulphate chelate and an amino acid chelate). 150g Mn/ha low rate was selected to be lower than the lowest quantity of Mn in the label recommended rates.

Table: Soil test values at Wunkar, South Australia, 2015.