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Queensland-based scientists are researching new and improved sugarcane varieties that require less fertiliser, thus reducing the nutrient run off into the ocean and impact on the natural environment such as The Great Barrier Reef.

The Co-operative Research Centre for Sugar Industry Innovation through Biotechnology (CRC SIIB) aims to discover smarter sugarcane that will ultimately reduce the sugarcane industry’s footprint on the environment.

CRC SIIB Project Leader Dr Susanne Schmidt said smarter sugarcane crops will rely more on nature and less on intervention, in which new sugarcane varieties will use resources more efficiently to drive productivity.

"Recent CRC SIIB research has shown that there is a genetic basis for improving the use of nitrogen by sugarcane. We think that more nitrogen efficient sugarcane varieties can be bred," Dr Schmidt said.

"Our theory is that through understanding how sugarcane acquires and uses nitrogen, we can use biotechnology to develop and breed varieties that need less nitrogen fertiliser to make the same amount of sugar and biomass."

One million tonnes of nitrogen fertiliser are manufactured around the world each year — nearly the same amount as is produced naturally by nitrogen fixing bacteria. The doubling of reactive nitrogen to the planet is of great concern as it interferes with the global carbon cycle with yet unknown consequences. One anticipated outcome is even more rapid increases in atmospheric CO₂ levels.

Dr Schmidt said that many people ask why and how nitrogen is so easily lost from a cropping system.

"It is a little like a good versus bad bacteria scenario. When a lot of nitrogen fertiliser is applied to soil, we upset the balance of soil bacterial population which plays a vital role in the earth's nitrogen cycle," she said.

"These bacteria convert the fertiliser into nitrogen compounds that are easily lost from soil. When the compounds come into contact with either rain or irrigation the nitrogen is washed into our waterways resulting in lower water quality. Bad bacteria also turn fertiliser nitrogen into greenhouse gases which contribute to global warming."

"Our research has shown that different types of sugarcane differ in their ability to 'mine' the soil for nitrogen and efficiently store and use it for growth. I have no doubt that efficient sugarcane varieties in combination with improved farm management will result in a more sustainable sugarcane production."

CRC SIIB research is an integral part of targeted research and development by the Australian sugarcane industry to work with State and Federal Governments towards a successful Reef Rescue Plan and preservation of the Great Barrier Reef.

The CRC SIIB acknowledges the ongoing support and input into this project by BSES Limited, CSIRO and the University of Queensland.

The CRC SIIB is an alliance of Australia's top sugarcane biotechnology expertise. The collaboration and expertise in this CRC is unparalleled through the combination of research institutions including four Universities, sugar industry research organisations, Federal and Queensland State Governments, and commercial partners. This CRC has a bold goal - to add new value to Australian sugarcane.

www.crcsugar.com

ENDS

For further information contact    
    
MEDIA RELATIONS    
CRC SIIB
Julie LLOYD  
T 07 3331 3309
M 0415 79 9890

NOTES The nitrogen production cycle This vital nutrient is formed in nature as part of an ongoing process of absorption from the atmosphere by 'nitrogen-fixing bacteria'. These specialist bacteria convert the unreactive atmospheric nitrogen gas into 'reactive nitrogen' much of which is deposited into soil. In soils, nitrogen occurs mostly in organic form as protein, which forms part of the so-called 'soil organic matter'. Nitrogen in soil is cycled by microbes which break-down protein into smaller compounds, including amino acids and ammonium, nitrate, which plants take up with their roots. By returning dead plant matter to the soil, the nitrogen cycle continues. Reactive nitrogen 100 years ago, scientists discovered how to make reactive nitrogen artificially by using heat and pressure, and man-made nitrogen fertiliser was born. Across the world, artificial nitrogen fertiliser, such as urea, ammonium or nitrate, now account for most of the nitrogen added to cropping systems. The high yields achieved in recent decades have been largely driven by improved crop sugarcane varieties in combination with a non-limiting supply of nitrogen. Nitrogen and runoff   The culprits are microscopically small but very effective. Man-made nitrogen fertilisers (urea, ammonium, nitrate) provide an easily-accessible food and energy source for soil bacteria. Rather than remaining bound to soil particles and waiting to be swallowed by plant roots, much fertiliser ends up in fuelling bacterial growth. This would be not so much of a problem if it wasn't for other interfering factors especially rainfall and irrigation which lead to loss of nitrogen from the soil. When soils get wet, oxygen becomes limiting and microbes will alter the nitrogen cycle to produce gases such as potent greenhouse gas nitrous oxide which escape to the atmosphere, adding significantly to greenhouse gas emissions. Also, mobile nitrogen forms, especially nitrate, can be leached from the soil during rainfall and irrigations events. Gaseous losses and leaching lead to nitrogen loss from the cropping system and pollute air and water.