Which is why they braved the pouring rain to rally on Friday, calling for an immediate injunction on Biosecurity Tasmania's decision to allow a South Australian company to export fresh, whole potatoes to Tasmania.

Among them was Terrence Rattray. Mr Rattray is the owner of Pyengana's Yum Tasmanian Gourmet Potatoes, which also operates a farm 380 hectare farm near Devonport.

RELATED: South Australian potatoes may be imported into Tasmania

He said the decision had been made based on "outdated" disease information.

"Biosecurity Tasmania's decision, whilst they may have ticked all the right boxes, in their own words they're using an out of date import requirement which is overdue for review," he said.

"All we're asking is that the import certificate they've issued be withdrawn or suspended until those reviews can take place."

He said a Biosecuity representative had admitted the criteria was outdated during a Zoom conference call with about 40 potato growers.

Minister for Primary Industries Guy Barnett said on Friday morning the decision had been made due to SA being free of two specific diseases - cyst nematode and bacterial wilt.

Mr Rattray said there were plenty of other diseases prevalent in SA which had not yet crossed the Strait.

"We're enjoying the most disease free state in Australia," he said.

"However we know there is other diseases prevalent in South Australia which are not an issue at this stage. Potato spindle tuber virus is an issue on the mainland as well."

Agronico Seed Potatoes CEO Robert Graham said his company had been working for the last four years on expanding Tasmania's potato exports into countries such as Indonesia.

"What alarms me most about this situation ... markets like Indonesia not only look at the diseases we have but where we are getting our potatoes from," he said.

"Even though those potatoes are for supermarkets the Indonesians perceive that as a risk ... and that's four years' hard work down the drain."

He said the Indonesian market had the potential to double Tasmania's potato industry.

Shadow Minister for Primary Industries Shane Broad was present at the rally.

"It's vital that the Government acts urgently to put an injunction in place or risk decimating the state's entire potato industry," he said.