Management and environment dictate tillering in grain sorghum, in combination with genetics.

Loretta Serafin1, Mark Hellyer1, Andrew Bishop1 and Annie Warren1

1 NSW Department of Primary Industries, 4 Marsden Park Road, Calala, NSW 2340., 


Tillering in grain sorghum can be either an advantage or a disadvantage, depending on the growing environment and the plant population. The challenge is to match the genetics and management to the site and expected environmental conditions. Commercial hybrids are marketed with information on the level of tillering likely to be expressed.

Three experiments were conducted in 2017-18 at Gurley, Mallawa and Breeza, in Northern NSW under rain-fed conditions, to compare the impact of plant density on tillering in four grain sorghum hybrids.

Hybrids were selected based on their levels of tillering from low to high.  The industry standard MR Buster was compared to Agitator, Brazen and Archer.

At Gurley and Breeza, four plant densities, 30, 60, 90 and 120,000 plants/ha were targeted. At Mallawa the 120,000 treatment was replaced with 45,000 plants/ha. The row spacing was 100cm at Breeza and Gurley and 150cm at Mallawa.

Total tiller number showed a negative correlation with increasing plant density. Differences in tillering were detected between hybrids, but their tiller level was not consistent with expectations. Archer produced the lowest number of tillers in all three experiments, and Agitator the highest. Differences (in tillering) between the hybrids were also smaller than anticipated. The difference in tillering was greatest at the lowest plant densities (1.5 tillers per plant, between hybrids) and these differences became smaller as plant density increased. There was no impact of plant density on yield at Gurley and Mallawa, or on harvest index across all sites. At Breeza; the mildest growing environment; Archer produced the highest grain yield.


The Soil Tech Project – Translating Soil Science into Digital Soil Management Tools for Agronomists and Land Managers

Andrea Koch1, Sam Duncan2

1 Andrea Koch Agtech Pty Ltd, 73 Kallaroo Road, Riverview, NSW, 2066,,

2 FarmLab, UNE SMART Region Incubator Level 2, W40 UNE Business School, Armidale, NSW, 2351,,


The Soil Tech Project is a collaborative project aimed at translating existing University of Sydney soil science into a suite of digital soil management applications for agronomists using User Experience Design and Agile Development. The partnership team of soil scientists, developers, agronomists and project manager are working across six development cycles over three years, to translate the science into code that is user centred, and field tested and ground truthed to provide innovative new approaches to soil management. The first development cycle is applying Latin Hypercube Sampling to defined sets of publicly available data, to create contiguous zones across a farm and/or within a paddock. The application then suggests a soil sampling design that ground truths these zones, using fewer samples than would normally be required to identify zones. The application has been field tested by agronomists. Development of this first tool will be completed by August 2019. The overall approach used in the Soil Tech Project is being observed and documented using an Action Research framework, in order to evaluate and replicate this innovative approach to translation of science into digital applications.



Soil wetting agents used to manage water repellence can benefit crops for more than one season though highest yields result from annual applications

G.P. McDonald1, S.L. Davies2

1 Department of Primary Industries and Regional Development, 444 Albany Highway, Albany, WA, 6330,,

2 Department of Primary Industries and Regional Development, 20 Gregory St, Geraldton, WA, 6530


Two small plot research experiments were established in 2016 at Darkan and Kojonup to investigate the longevity of banded soil wetting agents in duplex sandy gravel and loamy gravel soils in South-West Western Australia. Two commercial wetting agents were banded at sowing either in-furrow near the seed or banded on the furrow surface behind the press wheels. The experiments were designed to test residual or additive effects of the soil wetters by either applying or excluding them in different years to achieve different cumulative rates over the length of the trial. The 2017 crop rows were sown on or near the previous seasons rows for both trials but for the 2018 season off-row (inter-row) sowing was used at Kojonup. In the 2017 season at Kojonup some residual effect from the previous season was observed with the on-row sowing. In 2018, only treatments with fresh 2018 applications had crop yields greater than the control, with no residual effect of wetters. The Darkan site showed much smaller responses to any wetting agent treatment than Kojonup over both years. Some yield improvements were observed during the 2018 season with annual applications of wetting agents, but these were not as large as at Kojonup. Results over two sites and three seasons demonstrate that: a) annual applications are most effective at improving crop performance in repellent soils; and b) in some situations the amelioration effects of wetting agents applied in one season can carry over to improve crop performance in the next season.

Improved auxin level at panicle initiation stage enhance the heat stress tolerance in rice plants

*Naeem Sarwar1, Atique-ur-Rehman1, Omer Farooq1, Allah Wasaya2, 1Suhail Saliq and 3Khuram Mubeen

1Department of Agronomy, Bahauddin Zakariya University Multan 6000, Pakistan; *Corresponding E-mail:

2College of Agriculture, Bahauddin Zakariya University, Bahadur Sub-Campus Layyah, Pakistan

3Department of Agronomy, MNS-UAM, Multan, Pakistan


High temperature especially at flowering stage is major yield limiting factor as a result of global warming. Rice plants are most sensitive to high temperature at reproductive stage which significantly enhances the pollen sterility. Reproductive stage demand optimum level of phytohormones like auxin and other energy producing compound. We assume that application of naphthalene acetic acid (NAA) may improve the auxin level in heat stressed plants which may improve the pollen viability and crop yield. Pot experiment was conducted to examine the application different concentrations of NAA (0, 10, 20, 30, 50 μmol L-1) on rice crop grown under natural and heat stressed environment at flowering stage. NAA was applied immediately after flowering and then subjected to heat stress later on for few hours. It was found that heat stress at flowering stage significantly reduced the rice crop yield and quality but exogenous application of Naphthalene acetic acid (NAA) improved the crop tolerance to heat stress which leads toward better crop productivity.

More Profit from Nitrogen Program: delivering cross-sector collaboration in NUE research

M.White1, A.Williams2, C.Phelps3, F.Driver4, Kock5

1 ICD Project Services, 13 Flannel Flower Fairway, Shoal Bay, NSW, 2315,,  

2 Cotton Research and Development Corporation, 2 Lloyd St, Narrabri NSW 2390, ,

3 Dairy Australia Ltd, 40 City Rd, Southbank, VIC 3006,,

4 Sugar Research Australia, 50 Meiers Rd, Indooroopilly QLD 4068,,

5Hort Innovation Australia Ltd, 606 St Kilda Rd, Melbourne VIC 3004,,


The More Profit from Nitrogen Program (MPfN) is a four year partnership between Australia’s four most intensive users of nitrogenous fertilisers:  cotton, dairy, sugar and horticulture. The Program is conducting research and development to the increase nitrogen use efficiency (NUE) across the four sectors whilst improving profitable and sustainable use. By better understanding the influence of contributing factors on NUE in farming systems, the Program is:

  • Generating greater knowledge and understanding of the interplay of factors to optimise N formulation, rate and timing across industries, farming regions and irrigated/ non-irrigated situations;
  • Generating greater knowledge and understanding of the contribution (quantifying rate and timing) of mineralisation to crop or pasture N budgets; and
  • Generating greater knowledge and understanding of how enhanced efficiency fertiliser (EEF) formulations can better match a crop or pasture specific N requirements.

The Program is supported by $5.889 million funding from the Australian Government’s Rural Research and Development (R&D) for Profit program in addition to cash and in-kind contributions from each of the industry sectors, research organisations and collaborating partners equating to $9.757 million.

The MPfN Program is at the mid-way point of research activities but is already resulting in a more collaborative research effort to accelerate aligned research methodology, standardising terminology to reduce confusion for industry end users and communicating NUE outcomes using common indicators across the four industry sectors. MPfN is a proactive collaboration formed to expedite NUE across Australia’s intensive cropping and grazing industries to reduce environmental impact and increase the long-term sustainability of Australian farming businesses by increasing yield, product quality and overall profitability

Benefits to wheat and canola from upfront nitrogen fertiliser even when following a legume

Therese McBeath 1, Pilar Muschietti-Piana1, Michael Moodie2, Andrew Ware3, Rick Llewellyn1 Vadakattu Gupta1

1 CSIRO Agriculture and Food, Locked Bag 2, Glen Osmond, SA, 5064

2 Mallee Sustainable Farming and Frontier Farming Systems, Mildura, Vic, 3400

3South Australian Research and Development Institute and EP Ag Research, Port Lincoln, SA, 5606


Despite recent increases of nitrogen (N) inputs and one of the highest levels of adoption of soil-specific inputs of N fertiliser, a crop yield gap attributable to N remains on sandy soils. Over a 5 year period inclusive of decile 1 through to decile 9 seasons we have explored the effects of the source, rate and timing of N for increased productivity and reduced economic risk in low rainfall wheat and canola crops. While N application at the optimal rate is a primary driver of productivity and can reduce risk, we have identified that the N input for both wheat and canola is relatively insensitive to the timing of application. Utilising legumes in the sequence does increase the supply of N in the system, but the best productivity outcomes came from feeding wheat and canola with N from both legumes and fertiliser. A hybrid canola option has been shown to offer further yield gains per unit N input.

Potential greenhouse gas savings from balanced fertilisation

Graeme Blair1, Nelly Blair2

1 Agronomy and Soil Science, University of New England, Armidale, NSW, 2350.

2 Ourfing Partnership, 640 Boorolong Rd., Armidale, NSW, 2350


World fertiliser consumption has moved largely to high analysis, non-sulfur containing products which, in many situations, has led to sulfur (S) deficiency and consequently reduced nitrogen use efficiency (NUE). Calculations on data from field experiments conducted in China with rice and soybeans have been used to estimate the reduction in N2O emissions resulting from addition of S to mono-ammonium phosphate (MAP). Balanced nutrition using MAP+S in two experiments in China resulted in an increase in NUE of 9.4% in flooded rice and 12.6% in soybeans. Assuming a loss of 20% of fertiliser N as N2O in flooded rice and 10% in soybeans the increased N usage by the crop results in a potential N2O saving of 3.9 and 1.2 kg N2O/ha, respectively, in the two crops.

Balanced fertilisation and crop residue management can also be used to abate agricultural CO2 emissions. Using data from an extensive field research program, it is estimated that addition of S to MAP in a temperate climate can result in an incremental CO2 sequestration in excess of 8 t CO2/t applied S and this can be increased a further 4% if crop residues are retained. The increased crop residue produced, and retained, as a result of balanced fertilisation resulted in an estimated incremental CO2 sequestration of 3.7 t CO2/t S applied in a tropical crop production system to 5.5 t CO2/t S applied in a temperate system.

The spatial response of water-limited wheat yield to historical climate change across Western Australia since 1900

Chao Chen1, Andrew L. Fletcher1, Noboru Ota1, Roger A. Lawes1, Yvette M. Oliver1

1 CSIRO Agriculture and Food, PMB 5 Wembley, WA 6913,,


Climate change has affected crop yield potential in major rain-fed crop growing regions in Australia, including Western Australia (WA). Understanding changes in potential crop production due to past climate change can help guide the adaptation of cropping systems to future climate change. However, the spatial response of water-limited yield potential to historical climate change across the wheatbelt of WA is unclear. This research used APSIM (Agricultural Production Systems sIMulator) to simulate and map the spatial-temporal changes in water-limited wheat yield potential on ~5 km × ~5 km climate grids for 117 years (1900-2016) across WA. Observed decreases in rainfall resulted in a shift in the regional pattern of wheat yield potential towards the southwest by 70 km. Future climate change is likely to continue to impact water-limited wheat yield and its spatial pattern in WA. Cropping systems will need to continually evolve to cope with a changing climate, requiring improvements in every aspect of agronomy and genetics.

Design and performance of unique field chamber and CO2 control system for the investigation of biological impacts on wheats grown under fluctuating CO2

Mahabubur Mollah1, Glenn Fitzgerald2

1 Agriculture Victoria Research, DJPR – Horsham, Vic, 3400, Email:

2 Agriculture Victoria Research, DJPR – Horsham, Vic, 3400


The CO2 concentration [CO2] in the atmosphere is increasing, affecting plant growth and development. Free Air CO2 Enrichment (FACE) technology is used for the study of plant development under elevated CO2. However, criticism of the FACE technology is that it underestimates plant and crop responses to elevated [CO2] because rapidly fluctuating [CO2] within the FACE rings may force stomata to close more often and for longer periods than would occur under non-FACE conditions. Therefore, data from FACE rings cannot be used as validation for plant and crop responses in crop modelling. This report focuses on the engineering of chamber design to test constant vs. variable changes in [CO2] levels on crops. Three chambers were built, and a non-replicated study was conducted during the 2015 and 2016 seasons to assess the methodology and chamber design. The chambers were set up to test the impacts of constant ambient [CO2], elevated [CO2] and variable [CO2] on wheat biomass, yield and water use efficiency. The chamber design and control system performed as expected keeping 1 min average CO2 concentration within 1.8 µmol/mol (insignificant variation) to the set point of 610 µmol/mol for elevated CO2 treatments (fluctuating and constant).

A systems agronomy for sorghum in the Northern Grains Region

Daniel Rodriguez and Peter de Voil

The University of Queensland, Centre for Crop Sciences, Queensland Alliance for Agriculture and Food Innovation, Gatton Campus, Gatton, Queensland, 4343,,  


Over the last fifty years increases in grain yields have been the result of improvements from breeding,  from agronomy and the cropping system, and from their interactions. There is also no doubt that the same drivers will be responsible for future yield gains. This calls for R&D efforts to be directed towards identifying and communicating optimum combinations of agronomic management (M) and cultivars (G), or crop designs (GxM), that make best use of available resources and expected seasonal conditions i.e. the environment (E). Our present understanding of crop stress physiology indicates that in hindsight, those optimum crop designs should be known, while the main problem is to predict relevant attributes of the environment (E), at the time of sowing, so that optimum GxM combinations could be informed. Here we tested our capacity to inform that “hindsight”, by linking a crop model (APSIM-Sorghum) with outputs from two seasonal climate forecasting systems to answer “What is the value of informing optimum crop designs?” This was achieved by using the APSIM-Sorghum model and outputs from two seasonal climate forecasting systems (i.e. POAMA-2 and ACCESS-S1), to inform farmers’ decisions at different time scales, ranging from weeks to a few months in sorghum cropping. Results showed that that by linking APSIM-Sorghum and POAMA-2 to inform optimum crop designs at sowing could increase average sorghum profits by up to 143 AU$ ha-1 year-1; and that that by linking APSIM-Sorghum and ACCESS-S1 could be used to inform the likelihood of favorable soil temperatures over the following few weeks crucial to achieve uniform crop stands in winter sown sorghum.



The Australian Society of Agronomy is the professional body for agronomists in Australia. It has approximately 500 active members drawn from government, universities, research organisations and the private sector.

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