Critically low workforce levels driven by COVID-19 could see meat, fruit and vegetables rot at the farm gate, food suppliers warn, as staff shortages at supermarkets reach up to 40 per cent.

The Australian Fresh Produce Alliance, which represents fruit and vegetable growers, warned on Friday that the industry had been experiencing 20 to 30 per cent staff shortages over the past week, and on some days as much as 50 per cent.