Testing yield gains from 'slow-release' nitrogen

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Southern Farming Systems (SFS) trials are helping Victorian grower George Leishman explore the potential for a new off-farm venture that he hopes will help lift crop yields for Australian grain growers.

George, who farms 1300 hectares with his family at Streatham, about 80 kilometres south-west of Ballarat, commissioned the SFS trials to test whether a novel fertiliser coating from Thailand – used there in a range of crops – could similarly increase grain yields in Australia.

His interest in the biopolymer fertiliser coating containing silica and amino compounds from plants was triggered by reports that it was increasing rice yields in Thailand by up to 40 per cent.

The coating has not previously been tested in wheat or barley, though Rice Research Australia is planning rice crop trials at Jerilderie, NSW, later this year.

George was keen to learn if coated urea would also lift local cereal yields. In 2012 he initiated SFS trials in LongReach BeaufortPBR logo wheat and WestminsterPBR logo barley.

SFS trials and research coordinator Annieka Paridaen says that in these first trials there was a 15 per cent yield lift in wheat when the urea was coated and applied to the trial crop at growth stage (GS) 31.

Man sitting on end of truck, among wheat fields

Victorian grower George Leishman eagerly awaiting
the results of Southern Farming Systems trials in
December 2012.

PHOTO: Clarisa Collis

The coating was applied at a rate of four kilograms/ha to urea, which was applied to the trial crops at a rate of 150kg/ha.

“The wheat plots where the biopolymer coating was used yielded a tonne more grain than the control plots,” Ms Paridaen said. The coating also lifted barley yields by almost 0.5t/ha.

Chief agronomist with the Thailand-based company, Bio Polymer Ltd, Brad Burgess says the coating slows the release of nutrients. Research around the world has shown that making urea a slow-release fertiliser can reduce nitrogen losses to the environment and improve the efficiency of plant uptake.

For George, the trials have a personal significance. If the promising results are repeated in further trials this season, he hopes the coating might develop into a business that keeps him in the grains industry – and help his family overcome the age-old problem of succession planning when there is not enough land to support two brothers.

Ms Paridaen says further SFS trials in wheat, barley and canola at Westmere and Lake Bolac, in Victoria, in 2013 will seek to determine optimum fertiliser rates and application times to maximise the coating’s effect.

The coating is also being tested in other crops, such as maize, peanuts, rice and rubber, in Europe, Indonesia, Japan, Malaysia, South Africa, and South America.

Related Feature: Slowly, slowly trials for fertiliser efficiency

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