Senator Heffernan said evidence presented in Canberra last week pointed to fertiliser companies trying to alter fixed price contracts with farmers or lock producers into purchase agreements that were subject to changes in price.
"The ACCC will find those reports very interesting," he said.
"Farmers have told us the fertiliser market is still in chaos and hasn't improved since last year's Senate hearings.
"It seems pretty clear all the recommendations made by the committee last August still apply and need to be addressed thoroughly by the Government and the industry."
He said local prices were still out of kilter with the global market and "seem to be predatory".
"While I accept global prices are rising, when you look at the local price for single super it has doubled since last spring and it certainly has not jumped as much as that on world markets."
The Senate committee is also considering recommending mandatory testing for fertiliser in a bid to get fertiliser suppliers paying closer attention to the quality specifications of product they import or produce locally.
Farmers addressing last week's hearing reported various examples of high analysis fertiliser not measuring up to label specifications, with variations of 10 to 15 per cent reported by a producer from Peak Hill in Central West NSW.
Other evidence included reports of MAP fertiliser being heavily discounted for sale out of Melbourne after suppliers realised it did not measure up to label specifications.
Junee district farmer, John Martin told the hearing his independent tests results proved a consignment he used last year was different to what he was told he had bought.
The fertiliser company responsible accepted the independent tests and offered to recompense Mr Martin for the variation in the fertiliser ingredient.
However, the company had not offered to cover any reduction in crop production that may have resulted from the crop being short changed in nutrient application.
Senator Heffernan said the select committee was not impressed with the limited information offered to last week's hearing by the Fertiliser Industry Federation of Australia and wanted Incitec Pivot and Hi Fert representatives and possibly other fertiliser company bosses at the next hearing.
