Merger discussions between AWB and ABB Grain have ceased as a result of the parties being unable to agree on appropriate commercial terms.
The two companies had been involved in merger talks, but there had been issues over how a deal would be brokered and what value would be given to each company.
The news is likely to have mixed reactions within the farming sector.
Some farmer organisations believed a merger was a good thing to ensure strong domestic agribusinesses, while some were of the opinion that industry consolidation would erode grower choice.
Since the announcement AWB's share price on the Australian Stock Exchange has dropped by 33c to $2.52, while ABB's has fallen 27c to $7.23.