CBOT corn ends down on harvest pressure, profit-taking

CHICAGO, Oct 21 (Reuters) - Chicago Board of Trade corn futures fell on Tuesday on seasonal pressure from the ongoing U.S. harvest and profit-taking after a five-session rally, traders said.

• CBOT December corn CZ25 settled down 3-1/2 cents at $4.19-1/2 per bushel.

• Brokers noted chart-based resistance at around $4.25 a bushel. The December contract has spent this month bouncing between $4.25 and $4.09 a bushel as the U.S. harvest rolls on and market players await clarity on crop size.

• The American Petroleum Institute said it opposes legislation to expand year-round sales of E15 gasoline, which contains 15% ethanol, a reversal that underscores deepening tensions between the oil and ethanol industries.

• Tensions between the U.S. and Colombia, a major buyer of U.S. corn, added pressure. Colombia on Monday said it recalled its ambassador from Washington after U.S. President Donald Trump said he would raise tariffs on the South American nation over its drug policy.