The mother of Mia Ayliffe-Chung, a British woman killed last August while working in Australia, says Australian farmers are "making huge amounts of money out of our backpackers" which has "got to stop".
Rosie Ayliffe has told the BBC that Britons are "propping up their agricultural industry in effect".
Mia, 20, was working on a farm, which her mother said was "way over her head", in order to extend her working holiday visa when she was killed last year.
"People are making huge amounts of money out of our backpackers, and it's got to stop, really," said Mrs Ayliffe.
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"Their days are numbered," she said of Australian farmers' treatment of immigrants.
"But I can feel a fight coming on, I really can."
In the first year of their trips, many backpackers choose to do 88 days of rural work, usually agricultural, in order to get a visa to stay in the country for a second year.
Mrs Ayliffe is now campaigning for tighter regulation on the farmers and hostels that employ and house foreign workers during that time.
Mia, from Derbyshire, was stabbed at the hostel she was staying at while working on a nearby farm.
Another British backpacker, 30-year-old Tom Jackson from Congleton in Cheshire, sustained fatal injuries as he attempted to help her.
French national Smail Ayad has been accused of their murders. The case against him was adjourned in February at a magistrates' court in Townsville, Queensland.
