CBOT December corn settled down 8-3/4 cents at $3.61 per bushel, with technical selling accelerating as the contract fell below its previous contract low of $3.63-3/4.

Forecasts found very few signs of frost that could cut short the growing season for the late-maturing US corn crop.

Disappointing export data added pressure.

The US Department of Agriculture (USDA) reported export inspections of US corn in the latest week at 355,411 tonnes, below a range of trade expectations for 500,000 to 800,000 tonnes.

Concern about the US trade dispute with China also hung over the market, as new tariffs on Chinese goods went into effect over the US Labor Day weekend.

US and Chinese negotiators are due to meet in person in Washington this month, but no date has yet been set.

Ahead of the USDA's weekly crop progress report due later on Tuesday, analysts surveyed by Reuters on average expected the government to rate 58pc of the US corn crop as good to excellent, up from 57pc a week ago.