AUSTRALIA'S cotton production is expected to slump by nearly a quarter in the current marketing year as producers slash their plantings in the face of lower world prices, Rebecca Gowen, a specialist at the US Department of Agriculture's Canberra office, said.

The forecast for output of 4 million bales of cotton in the 2012-13 marketing year, which started in August, is down a further 6 per cent from Ms. Gowen's September prediction and would mean a 25 per cent decrease in production on the year. Ms. Gowen predicts plantings will be down as much as 30 per cent on the previous year due to competition from other crops.