The Riverland has been labeled as stubbornly non-compliant by the Fair Work Ombudsman, following the regulator's investigation into 447 agricultural businesses in regional hot spots across Australia.
Nationally, employers have been fined a total of $316,860 and the FWO has recovered $72,301 for underpaid workers.
Under the agriculture strategy, the regulator has labeled the Riverland - as well as Mildura Vic, and Coffs Harbour, NSW - as "stubbornly non-compliant".
A total of 34 businesses in the Riverland were investigated - with one investigation ongoing - with close to $50,000 in infringement notices issued for payslip and record-keeping breaches with more than $42,000 attributed to labour hire companies.
Six compliance notices were issued and recoveries were $11,841 for 32 workers.
Meanwhile, in Adelaide and the Adelaide Hills, where two investigations are ongoing, 16 businesses were found to be compliant while 14 were non-compliant.
Fines over payslips and record-keeping breaches exceeded $70,000 and four compliance notices were issued.
In both regions, the compliance notices were issued due to monetary contraventions, including the underpayment of casual minimum rate of pay, overtime for casuals and public holiday penalty rates.
In Adelaide and the Adelaide Hills, one also included failure to provide piecework records to pieceworkers.
Citrus SA chair Mark Doecke, Waikerie, said he believed the non-compliant companies made up a small portion of the region's employers.
"It costs us our labor pool because if we're not compliant, we won't have workers," he said.
"We do our best all the time because we know how important workers are to our industry.
"If we're looking at all the companies in the Riverland, it's a very small number that are non-compliant.
"It's not something I believe is common place and the vast majority of businesses are doing the right thing."
The FWO said it was unable to provide information on what percentage of the workforce the non-compliant businesses made up.
Investigations in the Sunraysia region resulted in 37 non-compliant and 16 compliant businesses, with fines totaling $136,344. Almost $129,000 of those fines were issued to labour hire companies with $14,389 recovered for 20 workers.
Fair Work Ombudsman Anna Booth said the regulator would prioritise the agriculture sector in 2023-24.
"With very high numbers of visa holders in the workforce, too many agriculture employers are breaching record-keeping and pay slips laws," she said.
"Breaches of record-keeping and pay slips laws often indicate increased risks of underpaying workers as well as non-compliance with other Commonwealth laws.
"Employers should access our free resources and get it right, or they will continue to face fines, backpayments and legal proceedings."