Asaja-Cordoba said that prices had sunk following a couple of years in which they saw a slight rise.
It also claimed the current situation was due to an influx of imports from third-countries.
Farmgate prices for one kilogram of Navelina oranges are around 0.10-0.14 euros, while for Salustiana oranges they are around 0.14-0.20 euros, it said.
"[These are] very inferior prices to those from the same time last year, despite the fact that production is expected to be similar or even lower than the previous season," it said.
The group also noted that many farmers were being paid less than the costs of production, which it estimated to be on average 0.15 euros per kilo.
"Much of the reason for this crisis is the trade agreement between the European Union and South Africa, which entered into effect in 2016 and allowed for citrus imports to this country until Nov. 30 with tariffs that in 2018 were 11.6% and that will continue to reduce until being eliminated in 2026," it said.
"The late South African varieties overlap with the first of the Spanish season, like the Navelina or Salustiana," it said, adding that imports from Uruguay had also become an issue for growers.
Asaja-Cordoba claimed that the Spanish Government did not believe there was reason to activate the safeguard clauses in the trade agreement with South Africa, and so far has only assisted growers by removing 50,000 metric tons (MT) of oranges and mandarins from the market.
"Unfortunately, the news from other countries like Turkey, Egypt and Morocco, where they are expecting record production, further increases our concern," it said. It expected those countries to compete with late Spanish citrus varieties.
The Spanish orange harvests in Cordoba are about a quarter complete.